GAS CHEMISTS HANDBOOK
COMPILED BY TECHNICAL COMMITTEE
SUB-COMMITTEE ON CHEMICAL TESTS
1916
C. C. TUTW1LER, Chairman
A. P. BEARDSLEY
S. R. CHURCH
W. H. FULWEILER
R. G. GRISWOLD
C. E. LEWARS
J. M. MOREHEAD
C. J. RAMSBURG
E. C. UHLIG
A. B. WAY
ALFRED H. WHITE
A. F. KUNBERGER, Editor
PUBLISHED BY THE AMERICAN GAS INSTITUTE
NEW'YORK CITY
\
ft^
CONTENTS
CHAPTER I.
RAW MATERIALS
Coal
Coke
Gas Oil
Purification Material
CHAPTER II.
PRODUCTS -OF GAS MANUFACTURE
Illuminating Gas
Ammonia
Tar
Cyanogen
CHAPTER III.
IMPURITIES IN GAS
Hydrogen Sulphide
Carbon Bisulphide
Ammonia
Tar
Naphthalene
Cyanogen
CHAPTER IV.
TAR PRODUCTS
" JHbtler<0$ (Drip Oil)
"
Tar Oils
Road Tars
Naphthalene Salts
CHAPTER V.
MISCELLANEOUS
Construction Materials
Alloys
Lubricating Oils
TABLES *
(The Institute is not responsible for statements of facts or
opinions expressed in advance papers. This paper is
subject to revision by the Board of Directors.)
(Copyright, 1916, by American Gas Institute.)
REPORT OF COMMITTEE ON CHEMICAL TESTS.
WRITTEN FOR THE ELEVENTH ANNUAL, MEETING OF THE AMER-
ICAN GAS INSTITUTE, OCTOBER, 1916, BY C. C. TUTWILER,
CHAIRMAN.
Since the last meeting of the Institute, the Committee on
Chemical Tests has directed its activities chiefly toward the
revision of the Gas Chemists' Handbook, compiled in 1914 by
Mr. W. H. Fulweiler.
Mr. Fulweiler, in presenting his report at the Ninth Annual
Meeting of the Institute, stated as follows :
The magnitude and delicacy of this work is fully realized
and this is presented primarily as a progress report. In time,
the Institute would be well repaid for the expense incurred in
the publication of such a handbook by the uniformity of practice
that would result from the adoption of these methods and by the
convenience to the gas chemist of having recognized standard
methods pertaining to the industry collected in one convenient
publication.
While this first issue of the Handbook was a very decided
step in the right direction, it was recognized that much was
still to be accomplished and the continuance of the work de-
volved upon the 1915 Committee on Chemical Tests. This
Committee was unable to do more than report satisfactory
progress at the 1915 meeting of the Institute and the same
Committee was re-appointed to continue the revision over
1916.
It was felt from the start that it was of first importance that
the work should be carried out by a committee whose activi-
ties covered as wide a field as possible, not only in the gas
industry but in collaterial lines as well, especially in the coke
oven and coal tar by-product industries which are becoming
452052
yearly more closely identified with the gas business. For this
reason, special effort was made to enlist the co-operation of
chemists skilled in these various lines and I have felt myself
and the Institute most fortunate in having secured the assist-
ance of the gentlemen who served with me on the Committee
in 1915 and 1916.
Mr. Fulweiler, in concluding his report, states :
It is urged that special attention be given to the question of
standard methods and to the peculiar conditions under which
samples must be taken in the gas industry.
The Committee has felt with Mr. Fulweiler that the stand-
ardization of methods of testing and sampling was the chief
consideration to which it should devote its attention, and in
the Handbook which we now offer for your consideration, we
have endeavored to round out as far as possible the work of
the first committee and to standardize and bring up-to-date
methods which have been developed or improved since the
work was inaugurated in 1914. It is hoped that owing to
the wide connections of the members of the Committee and
the various sources from which these methods have been
drawn that progress has been made toward the accomplish-
ment of this much desired result.
The Committee has devoted a considerable amount of time
to the consideration of proper methods of sampling, recog-
nizing the fact that unless the sample is properly taken, the
analysis might not only be worthless, but absolutely mislead-
ing. We have endeavored to have the directions for sampling
as well as for testing so clear that little difficulty will be en-
countered even by chemists of limited experience.
The Committee, recognizing the great progress being made
in the application of chemistry to the gas industry and feeling
that even companies of moderate size can well afford to have
on their staff chemists or men of some chemical training, has
kept in mind primarily the assistance of these men rather than
the engineer, although it has endeavored to present the subject
matter in a manner which may be easily understood by all.
It will be noted that no attempts have been made to interpret
the results of the analyses, nor have theoretical considerations
been touched upon to any great extent, it being felt that this
phase of the subject might better be left to succeeding com-
mittees, possibly to be covered in a separate publication.
We have included in the Handbook such of the most useful
tables of constants and data as are most frequently required.
But in view of the fact that there are now so many reference
books readily available, matter of this kind has been kept to a
minimum.
While the Committee feels that distinct progress has been
made in the Handbook, it is not prepared to recommend that
all of the methods contained therein be stamped with the
official approval of the Institute without further revision by
succeeding chemical test committees or by a special com-
mittee appointed for the purpose, except possibly the methods
covering the analyses of coal and coke, cement, and iron and
steel. All of these may safely be adopted, it is thought, since
the method for analyses of coal and coke is based on the work
of the Bureau of Mines and those for cement, iron and steel
are the official methods of the American Society for Testing
Materials. The desirability, however, of having the whole
work officially approved by the Institute seems apparent and
since its value would be so much increased by such action of
the Institute, the Committee feels that no unnecessary time
should be lost in taking the necessary steps to further stand-
ardize and enlarge the work.
In conclusion, I wish to express to the various members of
the Committee, my appreciation of their efforts in behalf of
the success of the Handbook and especially of the efforts of
those gentlemen not directly engaged in the gas business, who
have given their assistance. It seems proper in this connection
to make special mention of the work of Mr. S. R. Church,
Manager, Research Department, The Barrett Company.
I also wish to express my appreciation of the efforts of
Mr. A. F. Kunberger, who was appointed editor of the Hand-
book since the last meeting of the Institute and upon whose
shoulders has devolved most of the work in connection with
2d
getting into suitable form for publication the. data secured by
the Committee.
C. C. TUTWILER, Chairman,
A. P. BEARDSI,EY,
1 S. R. CHURCH,
W. H. FUIAVEH,KR,
R. G. GRISWOLD,
J. M. MOREHEAD,
E. C. UHWG,
C. R. RAMSBURG,
A. B. WAY,
A. H. WHITS.
(The Institute is not responsible for statements of facts or
opinions expressed in advance papers. This paper is
subject to revision by the Board of Directors.)
(Copyright, 1916, by American Gas Institute.)'
GAS CHEMISTS' HANDBOOK.
CHAPTER I.
COAL AND COKE.
The following determinations are covered in the analysis of
coal and coke :
Air-Drying Loss.
Moisture.
Volatile Matter.
Fixed Carbon.
Ash.
Sulphur.
Phosphorus.
Calorific Value.
Carbon.
Hydrogen.
Nitrogen.
Oxygen.
Shatter Test for Coke.
Apparent and Real Specific Gravity.
These determinations are based on reports of Committee
"E~4" of the American Society for Testing Materials, on Tech-
nical Papers No. 8 and No. 76 of the Bureau of Mines.
COAI, SAMPLING
The coal should be sampled at the time it is being unloaded
from railroad cars or other means of transportation.
To collect samples, a shovel or specially designed tool or
mechanical means should be used for taking increments of 10
to 30 pounds of coal. The size of the increments must depend
on the size and weight of the largest pieces of coal and im-
purities.
The increments must be regularly and systematically col-
lected, so that the entire delivery will be represented propor-
tionately in the gross sample. The frequency of collecting the
increments should be regulated so that a gross sample of not
less than 1,000 pounds will be collected.
If the coal contains an unusual amount of impurities, such
as slate, and if the pieces of such impurities are very large, a
gross sample of more than 1,000 pounds should be collected.
A gross sample of the above specified quantity should be
taken for delivery of 500 tons or less. When deliveries are
made in large quantities as in cargoes of from 2,000 to 12,000
tons, the size of the gross sample must be governed by the size
and amount of the free impurities. A gross sample of from
2,000 to 4,000 pounds is sufficient for reasonable accuracy un-
less the size and amount of the free impurities are unusually
large.
After the gross sample has been collected it must be system-
atically crushed, mixed and reduced in quantity to convenient
size for transmittal to the laboratory. The crushing should be
done by a mechanical crusher or by hand with a tamper or
hammer on a smooth and solid floor. In the absence of a
smooth, tight floor, the crushing may be done on a heavy
canvas, to prevent the accidental admixture of any foreign
matter. The mixing and reduction should be done by hand,
with a shovel, or mechanically, by means of riffles or sampling
machines.
The sizes to which the coal and impurities should be crushed
are approximately as here given.
Size to which pieces
Weight of sample should be broken
to be divided before each division
1,000 pounds or more I inch
500 pounds y± inch
250 pounds y-2 inch
125 pounds y% inch
60 pounds y^ inch
If the sample is prepared by hand, the mixing and reducing
should be done by the "long pile and alternate shovel" method
on amounts of 125 pounds or more, the procedure being as
follows :
The crushed coal is shoveled into a conical pile. A long
pile is formed by taking a shovelful at a time and spreading
it out in a straight line (8 to 10 feet long for a shovel holding
about 15 pounds). Each new shovelful is spread over the top
of the preceding one, beginning at opposite ends, the pile being
occasionally flattened with the flat side of the shovel and so on
until all the coal has been formed into one long pile.
By walking around the long pile, advancing a distance equal
to the width of the shovel, and systematically taking shovel-
fuls, and shoveling the coal to one side, alternate shovelfuls
being discarded, the sample will be halved in quantity.
Whenever the different increments of sample are collected
throughout some considerable period of time, each increment
or an accumulation of a number of increments, may be crushed
as soon as taken and the pieces of coal and impurities broken
sufficiently small to permit two or more reductions of total
accumulated sample before further crushing is necessary.
If the sampling should extend over any considerable period,
wrhat would otherwise be a gross sample may be wrorked down
in successive stages to samples of a size suitable for transmittal
to the laboratory, and these samples which should be approxi-
mately equal in quantity and as representing the several equal
parts of a delivery may be analyzed and the several analyses
averaged.
Preparation of Laboratory Samples.
''The quantity of sample sent to the chemist will be governed
by the relative proportion of free impurities and the practical
limits of fineness to which these impurities can be crushed at
the point of sampling. Ordinarily 5 pounds crushed to pass a
4-mesh screen is a convenient sample to send to the labora-
tory." In cases where it is not feasible to crush to 4 mesh
at the point of sampling, the weight of the sample sent to the
laboratory must conform to the following table :
Size of largest Minimum weight
impurities of sample
In. i,b.
V2 75
3/8 30
V* 9
3/16 or smaller 5
Samples of 125 pounds and less may be reduced to the 5-
pound quantity by a riffle sampler or on a canvas as follows :
The sample is placed on a canvas about 8 feet square and
mixed by raising first one end of the canvas and then the other,
thereby rolling the sample back and forth. After thoroughly
mixing in this manner, by gathering up the four corners of
the canvas, the sample will be formed into a conical pile and
is to be reduced in quantity by quartering. The cone is flat-
tened, its apex being pressed down with the flat side of the
shovel, or with a board, so that each quarter contains the ma-
terial originally in it. The flattened mass which should be of
uniform thickness and diameter is then marked off into quar-
ters with the board held edgewise or with a piece of sheet iron,
along two lines that intersect at right angles directly under the
apex of the original cone. The diagonally opposite quarters
are shoveled away and discarded and the space which they
occupied brushed clean. The coal remaining is successively
mixed, coned and quartered on the canvas until two opposite
quarters are equal to the quantity required to fill two contain-
ers holding about 5 pounds each. The coal should be well
packed in the containers so as to exclude air as much as possi-
ble.
Special Moisture Sample.
In the reduction of the gross sample to the sample for trans-
mittal to the laboratory, there will be an unavoidable loss of
moisture.
To determine the moisture content in the coal, a separate
special moisture sample must be taken.
This special moisture sample should contain approximately
100 pounds and should be accumulated by placing in a water-
proof receptacle, with a tight fitting and waterproof cover,
small parts of the freshly taken increments of the gross sample.
These parts should be broken to about ^2 inch in size as
accumulated.
The accumulated moisture sample must be reduced mechan-
ically or by hand as quickly as possible and immediately placed
in a container and sealed air-tight.
Sampling from Loaded Cars.
If it becomes necessary to sample coal from a loaded car,
the sample should be accumulated by digging ten or fifteen
holes, two or three feet deep, at systematically located points
over the car.
Sampling from a Storage Pile.
In sampling from a pile, first estimate the approximate sur-
face of the pile and then determine the relative distance be-
tween points for taking increments, sufficient in number to
insure the accumulation of the requisite amount of gross
sample.
Starting at three or four feet from the bottom of the pile,
take shovelfuls at the predetermined distance apart around or
along the pile on the same level. Then begin at a certain
distance up the pile and circle it again so on to the top.
Systematically alternate the depth of the holes, taking one
shovelful at the surface, the next one deeper, the next still
deeper, the fourth at the surface again and so on.
Sampling at the Mines.
The sample should be systematically accumulated through-
out at least one entire day's loading. The total weight of
8
sample taken should be governed by the size and amount of
impurities contained in the coal.
Samples should not be taken from the tops of loaded mine
cars as they are likely to be trimmed with lumps and also
because pieces of roof or draw slate may have fallen onto the
car.
Samples of the coal being shipped should be taken while the
railroad cars are being loaded. If any attempt is being made
to throw out impurities wThile loading, shovelfuls should be
taken from the slanting surface just before a new mine car
is dumped and after the pickers have finished cleaning the one
previously dumped. The shovel should be pushed well into
the coal to avoid getting only that on the surface from which
impurities have been picked, and the shovelfuls should be taken
systematically from various parts of the surface.
SAMPLING COKE.
The amount of gross sample of coke that should be accumu-
lated depends on the size of the coal and the size and amount
of impurities in the coal from which the coke is made.
In general coke is made from slack or crushed coal and in
the crushing and handling of the coal preparatory to charging
it into the ovens, it becomes so well mixed that errors due
to variations in its quality are minimized.
A ioo-pound sample of coke is usually sufficient, to obtain
accuracy for a single car, but where larger lots are to be
sampled especially when the entire output of a plant is to be
sampled, four or five separate samples of 50 pounds or more
should be taken and the results averaged.
Physical appearance as regards color and porosity is no in-
dication of the chemical analysis.
In general, the moisture content increases as the size of the
pieces of coke diminishes and to some extent this graduation
is true in the ash content as well. It is necessary, therefore,
especially in sampling run of oven coke that due care should
be exercised to obtain the proper proportions of lump and
fines. A great many small pieces from many different parts of
the lot should be taken by breaking off long slender fingers
from the lumps, and there should also be included pieces of
all sizes and shapes.
A special moisture sample should be taken as in the case of
coal, except that the time should not be spent in crushing finer
than i inch for the reason that in the crushing and mixing of
coke, the moisture loss is much more rapid than with coal.
Preparation of Laboratory Sample.
APPARATUS.
Air-Drying Oven. — The oven is to be used for air-drying
wet samples. It is not necessary but is economical where many
wet samples are received.1 -
Galvanised Iron Pans 18 x 18 x 1^2 Inches Deep. — For air-
drying wet samples.
Balance on Solution Scale. — For weighing the galvanized
pans with samples. It should have a capacity of 5 kilograms
and be sensitive to 0.5 kilogram.
Chipmunk Jaw Crusher. — For crushing coarse samples to
pass a 4-mesh sieve.
Roll Crusher or Coffee Mill Type of Grinder. — For reducing
the 4-mesh product to 2o-mesh. The coffee-mill type of
grinder should be entirely enclosed and have an enclosed
hopper and a receptacle capable of holding 5 pounds of coal.
This is to reduce the moisture losses while crushing.
Abbe Ball Mill, Planetary Disk Crusher, Chrome Steel Buck-
ing Board, or any Satisfactory Form of Pulverizer. — For re-
ducing the 2O-mesh product to 6o-mesh. The porcelain jars
for the ball mill should be approximately 9 inches in diameter
and 10 inches high. The flint pebbles should be smooth, hard
and well rounded. "The reduction in size of coke for the
laboratory should not be done by grinding in an apparatus
which will give up fine particles of iron to the sample. A
1 For details of air-drying oven, see Bownocker, lyord and Somermeier, "Coal"
Bulletin No. 9, 4th series, Ohio Geological Survey, P. 312 (1908); or F. M. Stanton
and A. C. Fieldner, "Methods of Analyzing Coal and Coke," Technical Paper No. 8,
Bureau of Mines, P. 4 (1912); or E. E). Somermeier, "Coal, Its Composition, Analysis,
Utilization and Valuation," P. 71, McGraw-Hill Book Co., (1912).
10
jaw crusher which will reduce to 8-mesh and an Abbe Ball
Mill for further reduction is recommended."
A Large Riffle Sampler with y* or y% inch Divisions.— For
reducing the 4-mesh sample to 5 pounds.2
A Small Riffle Sampler with y^. or y% inch Divisions. — For
dividing down the 20 and 6o-mesh material to a laboratory
sample.
An 8 inch 6o-mesh Sieve with Cover and Receiver.
Containers for Shipment to Laboratory. — A galvanized iron
or tin can with a screw top, which is sealed with a rubber gas-
ket and adhesive tape is best adapted to this purpose. Glass
fruit jars, sealed with rubber gaskets may be used if packed
carefully to avoid breakage in transit.
Upon receipt of the sample at the laboratory, it is to be pre-
pared for analysis by one of two methods, as follows :
(A) WHEN COAI, APPEARS DRY.
If the sample is coarser than 4-mesh (0.20 inch) and larger
in amount than 10 pounds, quickly crush it with the jaw
crusher to pass a 4-mesh sieve and reduce it on the larger riffle
sampler to 10 pounds, or to 5 pounds if it is crushed to pass a
6-mesh sieve; then crush it at once to 2O-mesh by passing
through rolls or an enclosed grinder, and take, without sieving,
a 60 gram total moisture sample, immediately after the ma-
terial has passed through the crushing apparatus. This sample
should be taken with a spoon from various parts of the 20-
mesh product, and should be placed directly in a rubber-
stoppered bottle.
Thoroughly mix the main portion of the sample, reduce on
the small riffle sampler to about 120 grams and pulverize to
6o-mesh by any suitable apparatus without regard to loss of
moisture.
After all the material has been passed through the 6o-mesh
sieve, mix and divide it on the small riffle sampler to 60 grams.
Transfer the final sample to a 4-ounce rubber-stoppered bottle.
- For details of riffle sampler see Bulletin No. 9, 4th Series, Ohio Geological
Survey, P. 313 (1908), or 15. K. Somermeier, "Coal, Its Composition, Analysis, Utiliza-
tion and Valuation," P. 73, McGraw-Hill Book Co., (1912).
II
Determine moisture in both the 60 and the 2O-mesh samples
by the method given under moisture.
Computation. — Compute the analysis of the 6o-mesh coal,
which has become partly air-dried during sampling, to the dry
coal basis, by dividing each result by I minus its content of
moisture. Compute the analysis of coal "as received" from
the dry coal analyses by multiplying by I minus the total
moisture found in the 2O-mesh sample.
(B) WHEN COAI, APPEARS WET.
Spread the sample on tared pans, weigh, and air-dry at room
temperature, or in a special drying oven, at 10 to 15° C. above
room temperature, and weigh again. The drying should be
continued until the loss in weight is not more than o.i per cent,
per hour. Complete the sampling as under dry coal.
Computation. — Correct the moisture in the 2o-mesh, air-
dried sample to total moisture "as received" as follows :
TOO— percentage of air-drying loss r
— X percentage of moist-
100
ure in 2o-mesh coal -f- percentage of air-drying loss = total
moisture "as received."
Compute the analysis to "dry coal" and "as received" bases
as under dry coal, using for the "as received" computation the
total moisture as found by the formula in place of the moisture
found in the 2O-mesh coal.
Notes. — Freshly mined or wet coal loses moisture rapidly on
exposure to the air of the laboratory, hence the sampling oper-
ations between opening the container and taking the 2O-mesh
total moisture sample must be conducted with the utmost dis-
patch and with minimum exposure to air.
The accuracy of the method of preparing laboratory samples
should be checked frequently by resampling the rejected por-
tions and preparing a duplicate sample. The ash in the two
samples should not differ more than the following limits :
No carbonates present 0.4 per cent.
Considerable carbonate and pyrite present. . . 0.7 per cent.
Coals with more than 12 per cent, ash, con-
taining considerable carbonate and pyrite i.o per cent.
12
Determination of Moisture.3
APPARATUS.
Moisture Oven. — This must be so constructed as to have a
uniform temperature in all parts and a minimum of air space.
It may be of the form shown here. Technical Paper No. j6,
Bureau of Mines.
FIG. i.
Provision must be made for renewing the air in the oven
at the rate of two to four times a minute, with the air dried
by passing it through concentrated sulphuric acid.
3 This method can not be applied to lignites which have to be dried at a much
higher temperature.
13
Capsules with Covers. — A convenient form, which allows
the ash determination to be made on the same sample, is the
Royal Meissen Porcelain capsule No. 2, % inch deep and i%
inches in diameter ; or a fused silica capsule of similar shape.
Ihis is to be used with a well-fitting flat aluminum cover.
Glass capsules with ground glass caps may also be used. They
should be as shallow as possible, consistent with convenient
handling.
METHOD.
(A) SIXTY-MESH SAMPLE.
Heat the empty capsules under the conditions at which the
coal is to be dried. Stopper and cover, cool over concentrated
sulphuric acid, specific gravity 184, for 30 minutes and weigh.
Dip out with a spoon or spatula from the sample bottle ap-
proximately I gram of coal; put this quickly into the capsule,
close and weigh at once.
An alternate procedure (more open to error) after trans-
ferring an amount slightly in excess of I gram is to bring to
exactly I gram in weight (0.5 milligram) by quickly removing
the excess weight of coal with a spatula. The utmost dispatch
must be used in order to minimize the exposure of the coal
until the weight is found.
After removing the covers, quickly place the capsules in a
pre-heated oven (at 104 to 110° C.) through which passes a
current of air dried by concentrated sulphuric acid. Close
the oven at once and heat for I hour. Then open the oven,
cover the capsules quickly and place them in a desiccator over
concentrated sulphuric acid. When cool, weigh.
(B) TWENTY-MESH SAMPLE.
Use 5 gram samples, weigh with an accuracy of 2 milli-
grams, and heat for il/> hours; the procedure is otherwise as
with the 6o-mesh sample. Methods of greater accuracy may
be found in the "Proceedings of the American Society for
Testing Materials," Vol. XIV, 1914, p. 421.
The allowable variations are as follows :
14
Same analyst Different analyst
per cent. per cent.
Moisture under 5 per cent. 0.2 0.3
Moisture over 5 per cent. 0.3 0.5
Determination of Volatile Matter.
APPARATUS.
Platinum Crucible with Tightly Pitting Cover. — The crucible
should be of not less than 10 nor more than 20 cubic centi-
meters capacity: of not less than 25 nor more than 35 milli-
meters in diameter ; of not less than 30 nor more than 35 milli-
meters in height.
Vertical Electric Tube Furnace; or a Gas or Electrically
Heated Muffle Furnace. — The furnace may be of the form as
shown here (p. 21, Technical Paper No. 76, Bureau of Mines).
It is to be regulated to maintain a temperature of 950° C.
(-J-2O0 C.) in the crucible, as shown by a thermo-couple in
the furnace.
METHOD.
Weigh I gram of the coal in a weighed 10 to 20 cubic centi-
meter platinum crucible, close with a capsule cover, and place
on platinum or nichrome-wire supports in the furnace chamber,
which must be at a temperature of 950° C. (+ 20° C.). After
the more rapid discharge of volatile matter has subsided, as
shown by the disappearance of the luminous flame, tap the
cover lightly to more perfectly seal the crucible and thus guard
against the admission of air. After heating exactly 7 minutes,
remove the crucible from the furnace and, without disturbing
the cover, allow to cool. Weigh as soon as cold. The loss
of weight minus moisture equals volatile matter.
ALTERNATE METHOD.
One gram of coal is placed in a platinum crucible of 20
cubic centimeters capacity. The crucible should have a tightly
fitting cover as above. The crucible is placed in the flame of
a Meker burner, size No. 4, having approximately an outside
diameter at the top of 25 millimeters and giving a flame not
less than 15 centimeters high. The temperature should be
FIG. 2.
i6
from 900 to 950° C., determined by placing a thermo-couple
through the perforated cover, which for this purpose may be
of nickel. The junction of the couple should be placed in
contact with the center of the bottom of the crucible; or the
temperature may be indicated by the fusion of pure potassium
chromate in the covered crucible (fusion of K2CrO4, 940° C.).
FIG. 3.
The crucible is placed in the flame about i centimeter above
the top of the burner and the heating is continued for 7 min-
utes. After the main part of the gases have been discharged
the cover should be tapped into place as above described.
17
When the gas pressure is variable it is well to use a U-tube
attachment to the burner to show the pressure.
Mechanical losses are incurred on suddenly heating peat,
sub-bituminous coal, and lignite; therefore they must be sub-
jected to a preliminary gradual heating for 5 minutes; this is
best done by playing the flame of a burner upon the bottom of
the crucible in such a manner as to bring about the discharge
of volatile matter at a rate not sufficient to cause sparking.
After the preliminary heating, transfer the crucible to the vol-
atile matter furnace or place in the full flame of the Meker
burner and heat for 6 minutes at 950° C., as in the regular
method.
The allowable variations are as follows :
Same analyst Different analyst
per cent. per cent.
Bituminous coals 0.5 i.o
Lignites I .o 2.0
Notes. — The cover should fit closely enough so that the car-
bon deposit from bituminous and lignite coals does not burn
away from the under side.
Regulation of temperature to within prescribed limits is im-
portant.
Determination of Fixed Carbon and Ash.
APPARATUS.
Gas or Electric Muffle Furnace. — The muffle should have a
good air circulation and be capable of having its temperature
regulated between 700° and 750° C.
Porcelain Capsules. — Royal Meissen Porcelain Capsules No.
2, y% inch de.ep and ify inches in diameter, or similar shallow
dishes.
METHOD.
Place the porcelain capsules containing the dried coal from
the moisture determination in a cold muffle furnace, or on
the hearth at a low temperature, and gradually heat to redness
at such a rate as to avoid mechanical loss from too rapid ex-
pulsion of volatile matter.
i8
Finish the ignition to constant weight ( — o.ooi gram) at a
temperature between 700° and 750° C. Cool in air and weigh
as soon as cold. Coals containing carbonate are best cooled
in a desiccator.
The results as determined by this method represent the
ignited mineral matter in the coal. The actual mineral matters
in the original coal are usually very different in weight and
composition. The application of corrections for sulphur pres-
ent in the iron pyrites and for the volatile ash constituent due
to hydration of clayey material, may be omitted for technical
purposes. For "corrected" ash see Jour. Ind. and Eng. Chem.,
Vol. 5, June, 1913, p. 523, and Technical Paper No. f6, Bureau
of Mines.
The allowable variations are as follows :
Same analyst Different analyst
per cent. per cent.
No carbonates present 0.2 0.3
Carbonates present 0.3 0.5
Coals with more than 12% of ash
containing carbonates and py-
rite 0.5 i .o
FIXED CARBON.
Compute as follows :
100 := (moisture + ash + volatile matter) — percentage of
fixed carbon.
SULPHUR.
ESCHKA METHOD.
Apparatus.
Gas or Electric Muffle Furnace, or Burners. — For igniting
coal with Eschka mixture and for igniting the barium sulphate.
Porcelain, Silica, or Platinum Crucibles or Capsules. — For
igniting coal with the Eschka mixture.
No. i. — Royal Meissen porcelain capsule, I inch deep and 2
inches in diameter. This capsule because of its shallow form,
presents more surface for oxidation and is more convenient
to handle than the ordinary form of crucible.
19
No. i. — Royal Berlin porcelain crucibles, shallow form, and
platinum crucibles of similar size may be used. Somewhat
more time is required to burn out the coal owing to the deeper
form, than with the shallow capsules described above.
No. o or oo porcelain crucibles, or platinum, alundum or
silica crucibles of similar size are to be used for igniting the
barium sulphate.
SOLUTIONS AND REAGENTS.
Barium Chloride. — Dissolve 100 grams of barium chloride
in 1,000 cubic centimeters of distilled water.
Saturated Bromine Water. — Add an excess of bromine to
1,000 cubic centimeters of distilled water.
Eschka Mixture. — Thoroughly mix two parts (by weight)
of light calcined magnesium oxide and one part of anhydrous
sodium carbonate. Both materials should be as free as possi-
ble from sulphur.
Methyl Orange. — Dissolve 0.02 gram in 100 cubic centi-
meters of hot distilled water and filter.
Hydrochloric Acid. — Mix 500 cubic centimeters of hydro-
chloric acid, specific gravity 1.20 and 500 cubic centimeters of
distilled water.
Normal Hydrochloric Acid. — Dilute 80 cubic centimeters of
hydrochloric acid, specific gravity 1.20 to I liter with distilled
water.
Sodium Carbonate. — A saturated solution, approximately 60
grams of crystallized or 22 grams of anhydrous sodium car-
bonate in 100 cubic centimeters of distilled water.
Sodium Hydroxide Solution. — Dissolve 100 grams in I liter
of distilled water. This solution may be used in place of the
sodium carbonate solution.
METHOD.
Preparation of Sample and Mixture. — Thoroughly mix on
glazed paper I gram of coal and 3 grams of Eschka mixture.
Transfer to the crucible or capsule and cover with about I
gram of Eschka mixture.
20
Ignition. — On account of the amount of sulphur contained
in artificial gas, it is preferable to heat the crucible over an
alcohol flame or in an electrically heated muffle, as in (a) fol-
lowing. The use of artificial gas is permissible only when
crucibles are heated in a muffle as in (b) following.
(a) Heat the crucible, placed in a slanting position on a
triangle, over a very low flame to avoid rapid expulsion of
the volatile matter, which tends to prevent complete absorp-
tion of the products of combustion of the sulphur. Heat the
crucible slowly for 30 minutes, gradually increasing the tem-
perature and stirring after all black particles have disappeared,
which is an indication of the completeness of the procedure.
(b) Place the crucible in a cold gas muffle and gradually
raise the temperature to 87o°-925° C. (cherry-red heat) in
about i hour. Maintain the maximum temperature for about
ij/2 hours and then allow the crucible to cool in the muffle.
Subsequent Treatment. — Remove and empty the contents
into a 200 cubic centimeter beaker and digest with 100 cubic
centimeters of hot water for ^< to ^4 hour, with occasional
stirring. Filter and wash the insoluble matter by decantation.
After several washings in this manner, transfer the insoluble
matter to the filter and wash five times, keeping the mixture
well agitated. Treat the filtrate amounting to about 250 cubic
centimeters, with 10 to 20 cubic centimeters of saturated
bromine water, make slightly acid with hydrochloric acid and
boil to expel liberated bromine. Make just neutral to methyl
orange with sodium hydroxide or sodium carbonate solution.
Then add I cubic centimeter of normal hydrochloric acid.
Boil again and add slowly from a pipette, with constant
stirring, 10 cubic centimeters of a 10 per cent, solution of
barium chloride. Continue boiling for 15 minutes and allow
to stand for at least 2 hours, or preferably over night at a
temperature just below boiling. Filter through an ashless filter
paper and wash with hot distilled w^ater until a silver nitrate
solution shows no precipitate writh a drop of the filtrate. Place
the wet filter containing the precipitate of barium sulphate in
21
a weighed platinum, porcelain, silica or alundum crucible,
allow a free access of air by folding the paper over the precip-
itate loosely to prevent spattering. Smoke the paper off grad-
ually and at no time allow it to burn with a flame. After the
paper is practically consumed, raise the temperature to approx-
imately 925° C., and heat to constant weight. The residue
of magnesia, etc., after bleaching, should be dissolved in hydro-
chloric acid and tested with great care for sulphur. When an
appreciable amount is found it should be determined quanti-
tatively.4
Blanks and Corrections. — In all cases a correction must be
applied either (i) by running a blank exactly as described
above, using the same amount of all reagents that were em-
ployed in the regular determination or (2) by determining a
known amount of sulphate added to a solution of the reagents
after these have been put through the prescribed series of
operation. If this latter procedure is adopted and carried
out, say, once a week or whenever a new supply of a reagent
must be used, and for a series of solutions covering the range
of sulphur content likely to be met with in coals, it is only
necessary to add to or subtract from the weight of barium
sulphate obtained from a coal. Whatever deficiency or excess
may have been found in the appropriate "check" in order to
obtain a result, that is more certain to be correct than if a
"blank" correction as determined by the former procedure is
applied. This is due to the fact that the solubility error for
barium sulphate, for the amounts of sulphur in question and
the conditions of precipitation prescribed, is probably the
largest one to be considered. Barium sulphate is soluble in
acids5 and even in pure water, and the solubility limit is reached
almost immediately on contact with the solvent. Hence, in the
event of using reagents of very superior quality or of exercis-
ing more than ordinary precautions, there may be no apparent
"blank" because the solubility limit of the solution for barium
sulphate has not been reached or at any rate not exceeded.
4 Journal American Chemical Society, Volume 21, page 1125 (1899).
5 Jour. Am. Chern. Soc. Vol. 32, p. 588 (1910); Vol. 33, p. 829, (1911).
22
ATKINSON METHOD.
Thoroughly mix on glazed paper I gram of the laboratory
sample of coal with 7 grams of dry sodium carbonate and
spread evenly over the bottom of a shallow platinum or por-
celain dish. Place on a triangle slightly elevated above the
bottom of a cold muffle. Heat the muffle gradually until a tem-
perature of 650° to 700° C. (dull red heat) has been obtained
in half an hour and maintain this temperature for 10 or 15
minutes.
The sodium carbonate should not sinter or fuse. The mix-
ture should not be stirred during the heating process. When
the dish has cooled sufficiently to handle, the matter should be
examined for black particles of unburned carbon and in case
such indications of incompleteness of the process should ap-
pear the dish should be replaced and heated for a short time.
When all the carbon is burned, remove the dish and digest the
contents with 100 to 125 cubic centimeters of warm water and
5 cubic centimeters of concentrated hydrochloric acid. Allow
the insoluble matter to settle, decant through a filter and wash
several times by decantation. Transfer to the filter adding a
few drops of a solution of pure sodium chloride if the insoluble
matter tends to pass through the filter. The washings should
be continued until the filtrate shows no alkaline reaction.
Make the filtrate just acid to methyl orange, add I cubic
centimeter of normal hydrochloric acid and proceed as de-
scribed under Eschka method.
THE PEROXIDE FUSION METHOD.
This method is most conveniently carried out in the Parr
Calorimeter. The charge consists of 0.5 gram of the air-dry
laboratory sample of coal, I gram of potassium chlorate pul-
verized to about 2o-mesh, and 10 grams of sodium peroxide
of the grade regularly prescribed for calorimetric purposes.
The coal and potassium chlorate are first added to the bomb
or fusion cup and thoroughly mixed, being careful to break
down any lumps that may form. The sodium peroxide is then
23
added, the container closed and the ingredients thoroughly
mixed by shaking.
After igniting and cooling the charge, dissolve the fusion
in a covered beaker, using 150 cubic centimeters of water.
Add concentrated hydrochloric acid just past the neutral
point (25 to 30 cubic centimeters). Add I cubic centimeter
of concentrated hydrochloric acid (specific gravity 1.19) in ex-
cess. Filter and wash with hot water, making the final bulk of
the solution approximately 250 cubic centimeters. Heat to boil-
ing and precipitate the sulphate by adding 10 cubic centi-
meters of a 10 per cent, solution of barium chloride. Proceed
as described under Eschka method.
Particular care should be taken in washing the precipitate
obtained by this method in order to remove all of the soluble
salts which are formed in the fusion process.
Determination of Sulphur in the Bomb Washings.
Where the precise content of sulphur is not required it may
be approximated from the washings from an oxygen bomb
calorimeter as follows :
After the combustion, the bomb is washed out thoroughly
with distilled water, and the washings collected in a 250 cubic
centimeter beaker. Six to eight cubic centimeters of dilute
(1:1) hydrochloric acid containing some bromine water are
then added and the solution is heated to boiling. The insoluble
matter is filtered off and washed free from sulphates with hot
water. The filtrate and washings which should have a total
volume of 200 cubic centimeters are made just neutral to
methyl orange with sodium hydroxide or carbonate solution,
i cubic centimeter of normal hydrochloric acid is added, and
the procedure completed as described under Eschka method.
The allowable variations in sulphur determinations are as
follows :
Same analyst Different analyst
per cent. per cent.
For coal 0.05 o.i
For coke 0.03 0.05
24
Determination of Phosphorus. (Recommended by
Committee E-4.)
To the ash from 5 grams of coal in a platinum capsule is
added 10 cubic centimeters of nitric acid and 3 to 5 cubic
centimeters of hydrofluoric acid. The liquid is evaporated and
the residue fused with 3 grams of sodium carbonate. If un-
burned carbon is present 0.2 gram of sodium nitrate is mixed
with the carbonate. The melt is leached with water and the
solution filtered. The residue is ignited, fused with sodium
carbonate alone, the melt leached and the solution filtered.
The combined filtrates, held in a flask, are just acidified with
nitric acid and concentrated to a volume of 100 cubic centi-
meters.
To the solution, brought to a temperature of 85° C., is added
50 cubic centimeters of molybdate solution and the flask is
shaken for 10 minutes. The precipitate is washed, on a filter,
six times, or until free from acid, with a 2 per cent, solution
of potassium nitrate, then returned to the flask and titrated
with standard sodium hydroxide solution. The alkali solution
may well be made equal to 0.00025 gram phosphorus per cubic
centimeter or 0.005 Per cent- f°r a 5 gram sample of coal, and
is 0.995 of one-fifth normal, (i) Or the phosphorus in the
precipitate is determined by reduction and titration of the
molybdenum with permanganate.
The advantage of the use of hydrofluoric acid lies in the
removal of silica. Fusion with alkali carbonate is necessary
for the elimination of titanium, which if present and not re-
moved with contaminate the phospho-molybdate and is said to
sometimes retard its precipitation.
Ultimate Analysis.
CARBON AND HYDROGEN.
The determination of carbon and of hydrogen is made with
a weighed quantity of sample in a 25-burner combustion fur-
nace of the Glaser type. The products of combustion are
thoroughly oxidized by being passed over red-hot copper oxide
25
and lead chromate, and are fixed by absorbing the water in a
weighed Marchand tube filled with granular calcium chloride
(CaCl2) and by absorbing the carbon dioxide in a Liebig bulb
containing a 3<>per cent, solution of potassium hydroxide
(KOH).
The apparatus used consists of a purifying train, in dupli-
cate, a combustion tube in the furnace, and an absorption train.
The purifying train consists of the following purifying re-
agents arranged in order of passage of air and oxygen through
them: Sulphuric acid, potassium hydroxide solution, soda
lime and granular calcium chloride. One of the trains is for
air and one for oxygen. In the sulphuric acid and potassium
hydroxide scrubbing bottles the air and the oxygen are made
to bubble through about 5 millimeters of the purifying reagent.
Both purifying trains are connected to the combustion tube by
a Y-tube, the joint being made tight by a rubber stopper.
The combustion tube may be of hard Jena glass, quartz or
fused silica. Its external diameter is about 21 millimeters,
and its total length is i meter. The first 30 centimeters of
the tube are empty : following this empty space is an asbestos
plug (acid washed and ignited) or in its place a roll of oxi-
dized copper gauze may be used; the next 40 centimeters are
filled with copper oxide wire ; a second asbestos plug separates
the copper oxide from 10 centimeters of fused lead chromate,
which, is held in place by another asbestos plug 20 centimeters
from the end of the tube. The end of the tube is contracted
for rubber tubing connection with the absorbing train.
The absorption train consists, first, of a Marchand tube
filled with granular calcium chloride (CaCl2) to absorb moist-
ure. The CaCl2 should be saturated with CO2 before using
The Marchand tube is followed by a Liebig bulb containing a
3O-per cent, potassium hydroxide solution, in which any pos-
sible impurities, as ferrous iron or nitrates, have been oxidized
by a little potassium permanganate (KMnO4). A guard tube
containing granular calcium chloride and soda lime is attached
to the Liebig bulb to absorb any dioxide escaping the potassium
26
hydroxide solution and any water evaporating from that solu-
tion.
The train is connected to an aspirator which draws the
products of combustion through the entire train. A guard
tube of calcium chloride prevents moisture from running back
into the absorption train. The suction is maintained constant
by a Mariotte flask. The advantage of aspirating the gases
through the train rather than forcing them through by pressure
is that the pressure on the rubber connections is from the out-
side, so that gas-tight connections are more easily maintained
than if the pressure is on the inside of the tube. The connec-
tions are made as tight as possible.
The usual test for tightness is to start aspiration at the rate
of about three bubbles of air per second through the potash
bulb, and then to close the inlet for air and oxygen at the
opposite end of the train ; if there is no more than one bubble
per minute in the potash bulb, the apparatus is considered tight.
Before starting a determination when the train has been idle
some hours, or after any changes in chemicals or connections,
a blank is run by aspirating about I liter of air through the
train, which is heated in the same manner as if a determination
on coal were being made. If the Liebig bulb and tube contain-
ing calcium chloride show a change in weight of less than 0.5
milligram each the apparatus is in proper condition for use.
A porcelain or platinum boat is provided with a glass weigh-
ing tube of suitable size, which is fitted with an accurately
ground glass stopper. The tube and empty boat are weighed.
Approximately 0.2 gram of the air-dry coal (6omesh or
preferably loo-mesh) are quickly placed in the boat. The boat
is at once placed in the weighing tube, which is quickly stop-
pered to prevent moisture change in the coal while weighing,
and transferring to the furnace. The absorption tubes are
connected and the boat and sample are transferred as quickly
as possible from the weighing tube to the combustion tube,
which should be cool for the first 30 centimeters. The copper
oxide should at this time be red hot and the lead chromate at a
dull red heat. As soon as the boat is in place (near the as-
27
bestos plug at the beginning of the copper oxide) the stopper
connecting with the purifying train is inserted and the aspir-
ation started with pure oxygen gas at the rate of three bubbles
per second. One burner is turned on about 10 centimeters
back from the boat, and the aspiration is continued carefully
until practically all the moisture is expelled from the sample.
The heat is then increased very gradually until all the volatile
matter has been driven off. In driving off the volatile matter
the heat must be applied gradually in order to prevent a too
rapid evolution of gas and tar, which may either escape com-
plete combustion or may be driven back into the purifying
train.
The heat should be slowly increased by turning on more
burners under the open part of the tube until the sample is
ignited : after which the temperature may be increased rapidly,
but care should be taken not to melt the combustion tube if a
glass one is being used. Any moisture collecting in the end of
the combustion tube or in the rubber connection joining it to
the calcium chloride tube is driven over into the calcium chlo-
ride tube by carefully warming with a piece of hot tile. The
aspiration with oxygen is continued for two minutes after the
sample ceases to glow, the heat is then turned off and about
1,200 cubic centimeters of air are aspirated. The absorption
bulbs are then disconnected, wiped with a clean cloth and
allowed to cool to the balance room temperature before weigh-
ing.
Percentage of hydrogen =
11.19 X increase in weight of CaCl2 tube
Weight of sample.
Percentage of carbon =
27.27 X increase in weight of KOHbulb
Weight of sample.
The ash in the boat is weighed and carefully inspected for
any unburned carbon.
Method with Electrically Heated Combustion Furnace.
For description of furnace and method see Technical Paper
No. 8, Bureau of Mines, revised edition 1913, p. 22.
28
Nitrogen.
The Kjeldahl-Gunning Method. — One gram of the coal
sample (coke and anthracite should be ground to an inpalpable
powder) is boiled with 30 cubic centimeters of concentrated
sulphuric acid (H2SO4), 7 to 10 grams of potassium sulphate
(K2SO4), and 0.6 to 0.8 gram of metallic mercury in a 500'
cubic centimeter Kjeldahl flask until all particles of coal are
oxidized and the solution nearly colorless. The boiling should
be continued for 2 hours after the straw colored stage has been
reached. The total time of digestion will be, for coal, from
3 to 4 hours and for coke and anthracite may be from 12 to 16
hours. The addition of a few crystals of potassium perman-
ganate (KMnO4), after the solution has been cooled enough
to avoid violent reaction, tends to insure complete oxidation.
After cooling, the solution is diluted to about 200 cubic centi-
meters with cold water. If the dilution with water has
warmed the solution, it should be again cooled and the follow-
ing reagents added: 25 cubic centimeters potassium sulphide
(K2S) solution (40 grams K,2S per liter) to precipitate the
mercury and so prevent the formation of mercurammonium
compounds Which are not completely decomposed by sodium
hydroxide, I to 2 grams of granular zinc to prevent bumping,
and finally enough strong sodium hydroxide (NaOH) solution
(usually 80 to 100 cubic centimeters) to make the solution dis-
tinctly alkaline. The danger of loss of ammonia may be mini-
mized by holding the flask in an inclined position while the
sodium hydroxide solution is being added. The alkaline solu-
tion runs down the side of the flask and forms a layer below
the lighter acid solution. After adding the alkaline solution,
the flask is at once connected to the condensing apparatus and
the solution mixed by gently shaking the flask.
The ammonia (NH3) is distilled over into a measured
amount of standard sulphuric acid solution to which has been
added sufficient cochineal indicator for titration. Care should
be taken that the glass connecting tube on the end of the con-
denser dips under the surface of the standard acid. The solu-
29
tion is slowly distilled over until 150 to 200 cubic centimeters
of distillate has passed over. To avoid mechanically entrained
alkali passing over into the condenser the rate of distillation
should not exceed 100 cubic centimeters per hour. The dis-
tillate is titrated with standard ammonia solution. Standard
NaOH or KOH solution with methyl orange, methyl red or
sodium alizarin sulphonate as indicator may be used instead of
ammonia and cochineal.
A blank determination should be made in the same manner
as described above, except that i gram of pure sucrose (cane
sugar) is substituted for the coal. The nitrogen found in
this blank is deducted from the result obtained with the coal.
Oxygen.
Oxygen is computed by subtracting the sum of the per-
centages of hydrogen, carbon, nitrogen, sulphur, water and ash
from 100. The result so obtained is affected by all the errors
incurred in the other determinations and especially by the
change in weight of the ash forming constituents on ignition.
A more nearly correct oxygen value may be obtained by
making the corrections indicated here.
Corrected oxygen = 100 — (C — C') + (H — H') + N +
H2O + S' + corrected ash.
In which C = total carbon
C' = carbon of carbonates
H = total hydrogen less hydrogen of water
H' = hydrogen from water of composition in
clay, shale, etc.
N = nitrogen
H2O = moisture as found at 105° C.
S = sulphur not present as pyrite or sulphate.
This is usually small.
3
30
Corrected Ash = Mineral constituents originally
present in the coal. For most
purposes this can be determined
with sufficient accuracy by, add-
ing to the ash, as found, five-
eights of the weight of pyritic
sulphur, the CO2 of carbonates
, and the water of composition of
clay, shale, etc.
Calorimetric Determination .
APPARATUS.
Combustion Bombs.6 — The Atwater, Davis, Emerson, Mah-
ler, Parr, Peters, Williams, or similar bombs may be used.
The bomb shall have an inner surface of platinum, gold, porce-
lain enamel, or other material which is not attacked by nitric
and sulphuric acids, or other products of combustion.
Calorimeter Jacket. — The calorimeter must be provided
with a water-jacket having a cover to protect the calorimeter
from air currents. The jacket must be kept filled with water
within 2 or 3° C. of the temperature of the room (except in
calorimeters which are totally submerged, where the jacket
temperature is controlled by a thermostat) and should be
stirred continuously by some mechanical stirring device.
Stirring of the Calorimeter Water. — The water in the calo-
rimeter must be stirred sufficiently well to give consistent ther-
mometer readings while the temperature is rising rapidly. The
speed of stirring should be kept constant. A motor-driven
screw or turbine stirrer is recommended and the speed should
not be excessive. This may be determined by adjusting the
temperature of the calorimeter to equality with that of the
jacket and allowing the stirrer to run continuously for 10
minutes. If the temperature of the calorimeter rises more
than about 0.01° C. in this length of time, the rate of stirring
6 "The Committee recommends the oxygen bomb. Where no oxygen bomb calo-
rimeter is available, the Parr, when carefully handled (preferably with electric igni-
tion and in conjunction with a Beckman thermometer) will give satisfactory results."
is excessive. Accurate results cannot be obtained when too
much energy is supplied by the stirring device or when the
rate of stirring is irregular. The portion of the stirring device
immersed in the calorimeter should be separated from the out-
side by non-conducting material, such as hard rubber, to pre-
vent conduction of heat from the motor or outside air.
Thermometers. — Thermometers used shall have been certi-
fied by a government testing bureau and shall be used with cor-
rections given on the certificate. This shall also apply to elec-
trical resistance or thermo-electric thermometers. Correction
shall also be made for the temperature of the emergent stem
of all mercurial thermometers, and for the "setting" of Beck-
mann thermometers. For accurate work, either Beckmann or
special calorimetric thermometers graduated to o.oi or 0.02° C.
are required. Such thermometers should be tapped lightly
just before each reading to avoid errors caused by the sticking
of the mercury meniscus, particularly when the temperature is
falling. A convenient method is to mount a small electric
buzzer directly on the top of the thermometer and connect it
up with a dry cell and a push button. The button should be
pressed for a few seconds immediately before each reading.
Oxygen. — The oxygen used for combustion shall be free
from combustible material. If an approximation of the sul-
phur is to be made from the bomb washings, the latter when
filled should contain at least 5 per cent, of nitrogen. The total
amount of oxygen contained in the bomb for a combustion
shall not be less than 5 grams per gram of coal. But the com-
bustion must be complete as shown by the absence of any
sooty deposit on opening the bomb after firing.
Firing Wire. — The coal in the bomb may be ignited by means
of either iron or platinum wire. If iron wire is used it should
be of about No. 34 B & S gauge and not more than 10 centi-
meters should be used at a time. A correction of 1,600 calories
per gram of wire burned is to be subtracted from the ob-
served number of calories.
Standardization. — The water equivalent of a calorimeter can
best be determined by the use of standard combustion samples
32
supplied by the Bureau of Standards. The required water
equivalent is equal to the weight of the sample multiplied by
its heat of combustion per gram divided by the corrected rise
in temperature.
The calorimeter shall be standardized by the combustion of
standard samples supplied by the Bureau of Standards, and
used according to the directions given in the certificates which
accompany them. A standardization shall consist of a series
of not less than five combustions of either the same or different
standard materials. The conditions as to the amount of water,
oxygen, firing wire, method of correcting for radiation, etc.,
under which these combustions are made shall be the same as
for coal combustions. In the case of any disagreement be-
tween contracting parties a check standardization may consist
of two or more combustions of standardizing samples.
MANIPULATION.
1. Preparation of Sample. — The ground sample is to be
thoroughly mixed in the bottle and an amount, approximately
i gram, is to be taken out and weighed in the pan or crucible
in which it is to be burned. Coals which are likely to be blown
out of the crucible should be briquetted. For anthracite and
coke the following procedure should be adopted: The inside
of the crucible is lined completely with a thin layer of ignited
asbestos, pressed well down into the angles. The sample is
then sprinkled evenly over the surface of the asbestos. After
weighing, the sample should preferably be immediately placed
in the bomb and this closed. This procedure is necessary to
avoid sublimation in the use of naphthalene for standardi-
zation.
2. Preparation of the Bomb. — The firing wire, if iron,
should be measured and coiled in a small spiral and connected
between the platinum terminals, using, if necessary, a piece of
platinum wire somewhat heavier than the iron wire, to make
the connection. The platinum and the iron must both be clean.
About 0.5 cubic centimeters of water should be placed in the
bottom of the bomb to saturate with moisture the oxygen used
33
for combustion. When the crucible is put in place in the
bomb, the firing wire should touch the sample. For combus-
tion of standardizing materials, or for coke, iron wire is prefer-
able to platinum.
3. Filling the Bomb with Oxygen. — Oxygen from the supply
tank is to be admitted slowly to avoid blowing the sample from
the crucible and the pressure allowed to reach 20 atmospheres
for the larger bombs or about 30 atmospheres for the smaller
bombs, so that the bomb shall contain an amount of oxygen
sufficient for complete combustion, namely at least 5 grams per
gram of coal or other combustible. For coke it will be found
better to allow a pressure of 5 atmospheres more than that al-
lowed for coal.
4. Calorimeter Water. — The calorimeter is to be filled with
the required amount of distilled water, depending upon the
type of calorimeter. The amount may be determined either
by measurement in a standard flask or by weighing. The
amount must be kept the same as that used in standardization
of the apparatus.
5. Temperature Adjustments. — The initial temperature in
the calorimeter should be so adjusted that the final temper-
ature, after the combustion, will not be more than i° C., pref-
erably about 0.5° C., above that of the jacket, under which
conditions the total correction for heat gained from or lost
to the surroundings will be small when the rise of tempera-
ture is 2 or 3° C., and the effect of evaporation will also be
small.
6. Firing Current. — The electric current used for firing the
charge should be obtained from storage or dry cells having an
electromotive force of not more than 12 volts, since a higher
voltage is liable to cause an arc between the firing terminals,
introducing additional heat, which cannot be measured with
certainty. The circuit should be closed by means of a switch,
which should remain closed for not more than 2 seconds.
When possible it is recommended that an ammeter be used in
the firing circuit to indicate when the firing wire has burned
out.
34
7. Method of Making an Observation. — The bomb when
ready for firing is to be placed in the calorimeter, the firing
wires connected, the cover put in place and the stirrer and
thermometer so placed as not to be in contact with the bomb
or container. The stirrer is then started and after the ther-
mometer reading has become steady, not less than 2 minutes
after the stirrer is started, temperatures are read at I -minute
intervals for 5 minutes and the charge is then fired, the exact
time of firing being noted. Observations of temperature are
then made at intervals depending upon the method to be used
for computing the cooling correction. When the temperature
has reached its maximum and is falling uniformly, a series of
thermometer readings is taken at i-minute intervals for 5
minutes for determining the final cooling rate.
8. Titration. — After the combustion, the bomb is to be
opened, after allowing the gas to escape, and the inside ex-
amined for traces of unburned material or sooty deposit. If
these are found, the observations shall be discarded. If the
combustion appears complete, the bomb is to be rinsed out
thoroughly and the washings titrated with a standard alkali
solution (i cubic centimeter = 0.02173 gram HNO3 = 5
calories) using methyl orange or methyl red indicator, to de-
termine the amount of acid formed. A correction of 230
calories per gram of nitric acid should be subtracted from the
total heat observed.
An additional correction of 1,300 calories per gram of sul-
phur in the coal should be made for the excess of difference
in heats of formation of SO2 and aqueous H2SO4 over the heat
of formation of aqueous HNO3. For details of titration see
Technical Paper No. 8, Bureau of Mines.
Computation of Results.
The following method of computation is recommended to
take the place of the Pfaundler or other similar formulas for
computing the cooking correction (radiation correction).
Observe (i) the rate of rise (r) of the calorimeter tem-
perature in degrees per minute for 5 minutes before firing;
35
(2) the time (a) at which the last temperature reading is made
immediately before firing; (3) the time (b) when the rise of
temperature has reached six-tenths of its total amount (this
point can generally be determined by .adding to the temperature
observed before firing, 60 per cent, of the expected temperature
rise, and noting the time when this point is reached) ; (4) the
time (c) of a thermometer reading taken when the tempera-
ture change has become uniform some 5 minutes after firing;
(5) the final rate of cooling (r2) in degrees per minute for 5
minutes.
When the temperature rise is not approximately known be-
forehand, it is only necessary to take thermometer readings at
40, 50, 60 seconds (and possibly 70 seconds with some calorim-
eters) after firing, and from these observations to find when
the temperature rise has reached 60 per cent, of the total.
Thus, if the temperature at firing was 2.135°, at 4° seconds,
3.05°, at 50 seconds 3.92°, at 60 seconds 4.16°, and the final
temperature was 4.200°, the total rise was 2.07° ; 60 per cent.
of it was 1.24°. The temperature to be observed was then
2.14° -j- 1.24° = 3.38°. Referring to the observations at 40
and 50 seconds the temperatures were respectively 3.05° and
3.92°. The time corresponding to the temperature of 3.38°
was therefore
40 + ^— ~ 3'°5 X 10 = 44 seconds.
3.92 — 3.05
The rate r is to be multiplied by the time b — a in minutes
and tenths of a minute, and this product added (subtracted
if the temperature was falling at the time a) to the thermom-
eter reading taken at the time a. The rate r2 is to be multi-
plied by the time c — b and this product added (subtracted if
the temperature was rising at the time c and later) to the
thermometer reading taken at the time c. The difference of
the two thermometer readings thus corrected, provided the
corrections from the certificate have already been applied,
gives the total rise of temperature due to the combustion. This
multiplied by the water equivalent of the calorimeter gives
the total amount of heat liberated.
36
The result, corrected for the heats of formation of HNO3
and H2SO4 observed and for the heat of combustion of the
firing wire, when that is included, is to be divided by the
weight of the charge to find the heat of combustion in calories
per gram. Calories per gram multiplied by 1.8 give the Brit-
ish thermal units per pound.
In practice, the time b — a will be found so nearly constant
for a given calorimeter with the usual amounts of fuel that b
need be determined only occasionally.
The results should be reduced to calories per gram or Brit-
ish thermal units per pound of dry coal, the moisture being
determined upon a sample taken from the bottle at about the
same time as the combustion sample is taken.
EXAMPLE.
Observations :
Water equivalent = 2,550 grams. Weight of charge —
1.0535.
Approximate rise of temperature = 3.2°.
60 per cent, of approximate rise = 1.9°.
Time Temperature Corrected temperature
10.21 15.244° (Thermometer corrections from the certificate)
.22 .250
•23 -255
.24 .261
.25 .266
(a) .26 .272 15.276°
Charge Fired:
>o° (d)
18.497°
(b)
27-2
17.200*
(c)
31
» 1 8. 500
32
.498
33
• 497
34
.496
35
•494
36
.493
37
Computation:
ri = 0.028° -f 5 = 0.0056° per minute, b — a = 1.2 minutes
The corrected initial temperature is
15.276° + 0.0056° X 1.2 = 15-283°
r:2 = 0.007° H" 5 = 0.0014° Per minute; c — b = 3.8 minutes
The corrected final temperature is 18.497° -f- (0.0014X3.8) = 18.502°
Total rise 18.502° — 15.283° = 3.219°
Total calories 2.550 X 3.219 = 8.209
Titration, etc. — 0.007
Calories from 1.0535 g. coal 8.202
Calories per g 7,785
or British thermal units per pound r4>°!3
(d) The initial temperature is 15.27°; 60 per cent, of the expected rise
is 1.9°.
The reading to observe is then 17.2°.
The results obtained by the above method of computation
and determination is the total heat of combustion at constant
volume, with the water in the products of combustion con-
densed to liquid at the temperature of the calorimeter, that is,
about 20° to 35° C.
Net heat of combustion at 20°, shall refer to results cor-
rected for latent heat of vaporization, as follows :
Total heat of combustion in B. t. u. -- 1,040 (hydrogen x
9) = net heat of combustion in B. t. u. per pound.
Also total heat of combustion in calories — 580 (hydrogen
x 9 = net heat of combustion in calories per gram.
Allowable Variations:
Per cent.
Same analyst o. 3
Different analysts 0.5
Shatter Test for Coke.
The apparatus consists essentially of a box capable of hold-
ing at least 100 pounds of coke, supported with the bottom 6
feet above a cast-iron plate. The doors on the bottom are so
hinged and latched that they will swing clearly away when
open and will not impede the fall of the coke. Boards are
38
placed around the cast-iron plate to prevent pieces of coke
from being lost.
Each sample is approximately 50 pounds and is selected at
random using a 2-inch tine fork. The sample is cool when
tested but not artificially dry.
The entire sample is placed in the box and dropped on the
cast-iron plate. No attempt is made at distributing or arrang-
ing the charge in the box before dropping.
The entire material is dropped four times onto the cast-iron
plate. The small material including the dust is returned to
the box with the large coke each time in order to represent as
nearly as possible, the practical conditions to which coke is
subjected.
After the fourth drop the coke is screened on a wire screen
with square holes, 2 inches in the clear.
The screen is held horizontally and is shaken once after the
coke is placed on it, but no attempt is made to force through
all the small pieces that might go through if they happened to
be placed differently on the screen.
The coke is weighed carefully before being placed in the
box the first time and the coke on the screen is weighed on
the same scales after the final screening. The coke is weighed
accurately to one-eighth of a pound and the result reported in
percentage of original coke that does not pass the screen after
the fourth drop.
Determination of the True Specific Gravity of Coal
and Coke Substance.
To determine the true specific gravity of coal and coke sub-
stance, the procedure is as follows : A sample of the 6o-mesh
coal, weighing approximately 3.5 grams is dried at 105° C.,
and introduced into a 50 cubic centimeter pycnometer with
about 30 cubic centimeters of distilled water. In order to
avoid loss of particles of the sample during boiling, a one-bulb
6-inch drying tube (a) (Fig. 4) is connected with the pycnom-
eter by means of a small piece of pure gum tubing (c). The
other end of the drying tube is connected \vith the aspirator.
39
Suction is applied and the contents of the flask are gently
boiled on the water bath (d) under partial vacuum for 3 hours
in order to expel all air from the sample. The pycnometer is
FIG. 4.
then detached, almost filled with boiled and cooled water, al-
lowed to cool to the temperature of the balance room, stop-
pered, and weighed. The temperature of the contents of the
40
pycnometer is taken immediately after weighing. Each pyc-
nometer is accurately calibrated and a table is constructed giv-
ing its capacity in grams of water at different temperatures.
True specific gravity is determined by use of the following
formula :
W
The specific gravity =
W — (W1 — P)
in which
W = weight of coke.
W = weight of pycnometer -f- coke + water to fill.
P — weight of pycnometer -j- water to fill.
Determination of the Apparent Specific Gravity.
The apparatus used for the determination of the apparent
specific gravity consists of a galvanized iron cylinder (Fig. 5)
which is filled with water to the water line, as indicated in the
figure. In the cylinder is immersed a hydrometer made of
brass. On the top of the hydrometer are two pans. The
upper one is used for weights and the lower one for the
sample. Below the air buoy is a brass cage perforated with
many holes to allow the air to escape when the instrument is
immersed. The cage carries the sample when it is weighed
under water.
The method of determining the apparent specific gravity is
as follows : Brass weights are placed on the upper pan until
the hydrometer sinks to a mark on the stem between the cop-
per pan and the buoy. The total weight required is recorded.
The weights are removed, and about 500 grams of the sample
in lump form (about 1^- to 2-inch cubes) are placed in the
copper dish. Brass weights are then added until the hydrom-
eter sinks to the mark on the stem. The difference in the
weights used gives the weight of the sample in air. The
sample is then carefully transferred to the brass cage below
the buoy. The weights on the upper pan are now adjusted
until the instrument again sinks to the mark on the stem.
The weight required to sink the hydrometer to the mark with
no sample on the upper pan nor in the brass cage minus the
FIG. 5.
42
weight required to sink it to the mark with the sample im-
mersed in the cage equals the weight of the coke in water.
Then
If the weight of the sample in air = x
and the weight of the sample in water — y
"1C
The apparent specific gravity -—
x y
Apparent specific gravity
And 100 X — — — ^ — - = percentage bv volume
true specinc gravity . .
of coke substance.
Also 100 percentage by volume of coke substance = per-
centage by volume of cell space.
In making apparent specific determinations of coke the sam-
ple should preferably be in lumps of nearly the same size and
shape. When the sample is immersed, the hydrometer should
be moved rapidly up and down in the water a number of times
in order to remove air bubbles. Since coke samples are porous
they take up water rapidly and should not be allowed to re-
main in contact with water more than 5 minutes during a deter-
mination. By observing the above-mentioned precautions satis-
factory results can be obtained. All samples should be thor-
oughly dry before specinc gravity determinations are made.
Ash Analysis.
For ash analysis follow the method outlined under refrac-
tories.
GAS OIL.
The following determinations are covered in the analysis of
gas oil :
Asphalt. Index of Refraction.
Bromine Number. Mean Boiling Point.
Cold Test. Mean Molecular Weight.
Distillation. Paraffin.
Flash Point. Specinc Gravity.
Fire Point. Specinc Heat.
Heating Value. Sulphur.
Heat of Vaporization. Water.
43
It is not recommended that all are necessary for routine
analysis, but special circumstances may require more extended
investigation as a means of identifying the source of an un-
known sample when such determinations may be of great value.
There are a number of methods in the literature .that may
be used for the empirical determination of the relative propor-
tion of the various classes or groups of hydrocarbons in gas
oils. These methods, however, have not had the extensive
use and acceptance that would seem necessary for their incor-
poration in the Handbook at this time.
Asphalt.
The determination of asphalt is still in an unsatisfactory
state as there are a number of precipitants used for the pur-
pose, viz., petroleum ether, alcohol, ether, amyl alcohol, ethyl
acetate, butanon. The asphalts thus obtained vary quite wide-
ly both as to quantity and hardness and there does not seem to
be any well denned relation existing between the results ob-
tained with the different precipitants on different samples of
oil.
The more generally recognized precipitant is naphtha, and
the method according to Engler, is as follows :
QUANTITATIVE DETERMINATION.
Asphalt Insoluble in Naphtha. — Five grams of oil are shaken
in a 500 cubic centimeter bottle with 40 times its volume (220
cubic centimeters, assuming the specific gravity to be 0.9) of
normal benzene. If the oil contains only a little asphalt, as
much as 20 grams of oil may be taken with the corresponding
amount of naphtha. After standing at least 24 hours at a
temperature between 15° and 20° and away from direct sun-
light, the solution is decanted through two filters folded to-
gether (white ribbon S. & S.). The residue is washed with
naphtha till the filtrate gives no more oily residue. To prevent
the asphalt from becoming insoluble on standing, it is at once
dissolved in hot benzol, the main mass evaporated from a
flask and the remainder in a tared vessel, the residue dried at
44
IO5° and weighed. Foreign substances precipitated by naph-
tha and insoluble in benzol can be separately determined by
using a weighed filter paper. If the suspended asphalt is to be
determined, the amount of asphalt is determined in the original
oil as well as in the filtered oil; the difference gives the sus-
pended asphalt. In the different crude oils the amount of as-
phalt runs parallel to the amount of coke obtained on distilla-
tion.
The German specifications for the naphtha require a gravity
at 15° C. of 0.695-0.705, boiling range 65° €.-95° C. with 100
cubic centimeters using a 3-bulb Le Bel Henninger Column 40
centimeters long. Not over 2 per cent, should dissolve in a
mixture of 20 per cent, fuming and 80 per cent. 1.84 H2SO4,
using equal volumes and shaking for 15 minutes.
Bromine Number.
From 0.3 to 0.5 gram of oil is weighed into a glass stoppered
8-ounce bottle. Ten cubic centimeters of bromine solution is
run from the burette, the bottle is then cooled in ice water and
25 cubic centimeters of 10 per cent, potassium iodide solution
is added shaking the bottle, but preventing any of the solution
from getting on or near the stopper. Add I or 2 cubic centi-
meters of starch solution and titrate against standard sodium
thiosulphate solution. The reaction is as follows :
Br2 + 2KI = 2KBr + L,
I2 + 2Na2S2O3 = 2NaI + Na2S4O6.
Calculation. — Cubic centimeters of bromine used x equiva-
lent to thiosulphate solution = equivalent volume of thiosul-
phate.
Equivalent volume of thiosulphate — thiosulphate added in
titration = cubic centimeters of thiosulphate used.
Cubic centimeters of thiosulphate used x 0.008 = grams of
Grams of bromine absorbed X 100
bromine absorbed. _. — - — — -
Grams of oil used
bromine number.
Solutions. — The thiosulphate solution is made up to contain
45
24.8 grams of C. P. sodium thiosulphate (Na2S2O35H2O) per
liter.
The bromine solution is made up with dry carbon tetra-
chloride and standardized with the thiosulphate. One cubic
centimeter of the bromine solution should equal approximately
1.5 cubic centimeters of thiosulphate solution.
Distillation.
The apparatus shall consist of the following standard parts :
(i) FLASK.
The distillation flask shall be a standard 100 cubic centi-
meter Engler distilling bulb having the following dimensions
(see Stillman's "Engineering Chemistry").
Diameter of bulb 6.5 cm.
Length of neck 15.0 cm.
Diameter of neck 1.6 cm.
Surface of oil to tubulure 9.0 cm.
Length of tubulure 10.0 cm.
Angle of tubulure 75°
A 3 per cent, variation from the above measurements will
be allowed.
(2) THERMOMETER.
High temperature nitrogen-filled Fahrenheit thermometer
constructed according to the following specifications :
(1) To be made of special German hardened glass.
(2) Diameter of stem not less than 6.75 millimeters nor
more than 7.25 millimeters.
(3) Length of thermometer not less than 335 millimeters
nor more than 350 millimeters.
(4) Length of thermometer between o° mark and 1,000°
mark not less than 285 millimeters nor more than 300 milli-
meters.
(5) Length of bulb to capillary not less than 20 millimeters
nor more than 22 millimeters.
(6) Diameter of bulb at center of same not less than 5.25
millimeters nor more than 6.25 millimeters.
4
46
(7) Mercury column to rise from 60° to 200° in not more
than 5 nor less than 3 seconds when plunged into boiling water.
(8) To be correct within i° at 212° and 750° after 25 suc-
cessive oil tests.
(3) CONDENSER.
Liebig glass condenser and tube as follows :
Length of body of jacket 300-350 mm.
Width of body of jacket 25- 40 mm.
Length of inner tube 530 mm.
Width of inner tube 12- 15 mm.
Width of end of inner tube 20- 25 mm.
(4) STANDS.
Two iron stands provided respectively with one universal
clamp for holding condenser, and one light grip arm asbestos
lined clamp for holding the bulb.
(5) BURNER AND SHIELD.
Bunsen burner with tin shield 8 inches long by 3 inches in
diameter. The shield has a sight hole in the same for observ-
ing the flame.
(6) CYLINDERS.
Ten glass cylinders, 25 cubic centimeters capacity, gradu-
ated to i/io cubic centimeter.
SETTING UP APPARATUS.
The apparatus is set up as shown in Fig. 6, the thermometer
being so placed that the top of the bulb is opposite the middle
of the tubulure. All connections should be tight.
Distillation Test.
One hundred cubic centimeters of the oil to be tested are
placed in a weighed bulb, and after adjusting the thermom-
eter, shield, condenser, etc., the distillation is commenced, the
rate being so regulated that I cubic centimeter passes over
every minute. Cold water should be passing through the con-
denser during the first half of the distillation. When the
47
thermometer reaches 600° F., the cold water should be re-
moved from the condenser and hot water substituted. The
receiver is changed as the mercury column just passes the
fractionating point. At the end of the distillation, or when no
more oil distils over, the flask is disconnected from the con-
denser, inverted and two burners are used to complete the
coking.
FIG. 6.
The fractionating points in the distillation are at every 50°
F., i. e., at 300°, 350°, 400° F., etc. The number of cubic
centimeters obtained between each cutting point will give the
per cent, by volume distilling between these temperatures.
48
The per cent, by weight is obtained as follows : Multiply the
per cent, by volume of each fraction by its specific gravity and
divide by the specific gravity of the original oil.
In case the oil contains more than 2 per cent, of water, it
should be dried by the following method before carrying out
the distillation: A definite volume of oil is placed in a copper
still and heat gradually applied until all water has distilled
over, returning any oil to the still that has been carried over
with the water.
For more accurate work the emergent stem correction should
be applied to the observed temperature.
This has been determined by the Bureau of Standards to be
approximately as follows for a thermometer in the position as
used in the distillation test :
200° C 4.50° C.
250° C 6.0° C.
300° C 10.5° C.
350° C 15.5° C.
Flash and Fire Tests.
DIRECTIONS FOR OPERATING TAGUABUE OPEN CUP.
General Directions.
1. Test shall be made in a room partially darkened.
2. The cup shall be protected by a surrounding screen, 16
inches square, 30 inches high, open at top and front, and
painted black inside. Drafts caused by the breath of the oper-
ator shall be carefully avoided.
3. A fresh sample shall be used for each test.
4. The instrument must stand level.
Preparation of Water Bath. — Fill the metal bath with water
at a temperature of 25° C. (77° F.) so that when the glass cup
is in place, the water in bath will come to the rim of the metal
cup.
Preparation of Sample. — Suspend a calibrated thermometer
(see specifications) in the center of the cup with the top of
the bulb of same y2 inch below the upper level edge of the
49
glass cup. Bring sample to be tested to a temperature of
15.5° C. (60° F.). Fill the glass cup with 59 cubic centimeters
of the sample. See that there is no oil on the outside of the
cup or its upper edge, using a filter paper to clean the cup.
Remove air bubbles, if any, from the surface of the oil.
NOTE. — The horizontal flashing-taper guide wire (as speci-
fied by direction of the manufacturer) Is not to be used In these
tests.
Application of Heat to Oil Cup. — Heat the bath with an
alcohol, gas or other flame, so adjusted that the temperature
will not be raised faster or much slower than i° C. (1.8° F.)
per minute, without removing the flame.
Description of Test Flame. — The test flame shall be spher-
ical in form, and shall have a diameter equal in size to the bead
furnished herewith, which may be attached to the cover of the
water bath. This flame is best produced by passing gas
through a straight thin metal blow-pipe tube. (See Eimer and
Amend Catalogue C (1913, p. 54, Item 784) or Scientific Ma-
terials Co. (1912, p. 69, Item 618) or C. J. Tagliabue special
tube.
Initial Test. — When the sample under test reaches a temper-
ature of 30° C. (86° F.) the first test shall be made, and tests
shall be made thereafter at each rise of i° C. (1.8° F.) until
the flash point is reached.
Method of Applying Test Flame.
(Two Methods, both to be used and reported.)
(A) Sweep Method. — Holding the burner tube in a truly
horizontal position the flame is passed in a straight line con-
tinuously across the center of the cup, with the tube touching
the edge of the cup. The time for one sweep from edge to
edge of the cup to be gauged to I second. The temperature
at which a flame first appears anywhere on the surface of the
oil shall be considered the flash point.
(B) Dip Method. — Holding the burner tube in a vertical
position with the flame 3 inches above the surface of the
sample, the flame is quickly lowered to Y% inch from the sur-
50
face of the sample near the outer edge of the cup, and with-
drawn; entire operation consuming one second. This opera-
tion is quickly repeated at three equidistant points around the
circumference of the cup. The temperature at which a blue
flame jumps from the taper to the surface of the oil is the
flash point.
DIRECTION FOR OPERATING THE EUJOTT OR N. Y. STATE TESTER.
General Directions.
1. Test shall be made in a room partially darkened.
2. The cup shall be protected by a surrounding screen, 16
inches square, 30 inches high, open at top and front, and
painted black inside. Drafts caused by the breath of the oper-
ator shall be carefully avoided.
3. A fresh sample shall be used for each test.
4. The instrument must stand level.
Preparation of Water Bath. — Fill the metal bath with water
at a temperature of 25° C. (77° F.) so that when the metal
cup is in place, the water in bath will come to the rim of the
metal bath.
Preparation of Sample. — Bring the sample to be tested to a
temperature of 15.5° C. (60° F.). Fill the metal cup with
the sample to such a point that the surface of the oil will be
1/8 inch below the lower inner flange. Remove air bubbles, if
any, from the surface of the sample. Place the glass cover in
position and insert the calibrated thermometer (see specifica-
tions) through the cork in the central opening so that the top
of the bulb will be % inch below the surface of the sample.
Application of Heat to Oil Cup. — Heat the bath with an al-
cohol, gas or other flame, so that the temperature will not be
raised faster or much slower than i° C. (1.8° F.) per min-
ute, without removing the flame.
Description of Test Flame. — The test flame shall be spheric-
al in form, and shall have a diameter equal in size to the
bead furnished herewith, which may be attached to the cover
of the water bath. This flame is best produced by passing gas
through a straight thin metal blow-pipe tube. (See Eimer and
Amend Catalogue C (1913, p. 54, Item 704) or Scientific Ma-
terials Co. (1912, p. 69, Item 618) or C. J. Tagliabue special
tube.
Initial Test. — When the sample under test reaches a temper-
ature of 25° C. (77° F.) the first test shall be made. Tests
shall be made thereafter at each rise of i° C. (1.8° F.) until
the flash point is reached.
Method of Applying Test Flame. — Holding the burner tube
at an angle of 45°, the flame is passed through the side open-
ing in the cover to a point half way between the surface of
the sample and the cover. The time consumed in entering
and withdrawing the flame is to be I second. The tempera-
ture at which a blue flame is seen through the glass is the
flash point.
Specification for Thermometer for Flash Point Tests.
To be used with Tagliabue and Elliott or N. Y. State Testers.
The thermometer shall be graduated from — 10° to rj-iio°
C. in i° intervals. There shall be a small reservoir above the
110° mark. The thermometer shall be finished at the top with
a small glass ring.
The stem shall be made of enamel backed thermometer tub-
ing, but not of Jena I6111 glass. The bulb shall be made of
Jena I6111, Corning normal, or Jena or Corning borosilicate
glass.
Every fifth graduation shall be longer than the intermediate
ones and the marks shall be numbered at every 10° interval.
The graduation marks shall be clear cut and fine, and the num-
bering clear and distinct.
Each thermometer shall be provided with a suitable case.
A serial number for identification shall be engraved on the
stem.
All material and workmanship shall be of the bes,t grade.
Accuracy. — The maximum error at any point shall not ex-
ceed three-tenths (0.3) degree Centigrade.
52
Dimensions :
Total length, not over 300 millimeters.
Diameter stem, from 5.5 to 7 millimeters.
Diameter bulb, same as stem.
Diameter capillary, not less than o.i millimeter.
L,ength of bulb, from 8 to 12 millimeters.
Distance — 10° to bottom of bulb, from 40 to 60 milli-
meters.
Distance — 10° to no0 on scale, from 180 to 220 milli-
meters.
Heating Value.
Refer to Heating Value of coal analysis on page 30.
Heat of Vaporisation.
The heat of vaporization may be calculated with sufficient
accuracy for purpose of design from the mean molecular
weight and the mean boiling point and specific heat from
Trouton's rule.
Mean boiling point
(Heat of vaporization) = 20. — — • — ;! .
Mean Molecular Weight
The total heat of vaporization — sensible heat from room
temperature to boiling point + latent heat of vaporization so
there must be added (mean boiling point — room temperature)
(specific heat).
Refractive Index.
The Zeiss refractometer is recommended for the refractive
index at a temperature of 25° C., at which point all fractions
of the usual gas oils are sufficiently liquid for observation. As
detailed instructions are furnished with the instrument they
are not repeated here.
The use of the refractive index instead of the specific grav-
ities for the fractions of gas oils is recommended as giving
really more information and requiring but a fraction of the
time to determine.
53
Mean Boiling Point.
This figure is the arithmetical mean of the temperature at
which equal volumes of the oil distil off.
The oil is distilled in the usual form of apparatus and the
temperatures noted when the first drop, 10 per cent., 20 per
cent., 30 per cent., etc. have distilled over. The sum is divided
by the number of fractions. The mean boiling point is ex-
pressed in absolute temperature for use in calculating the heat
of vaporization.
Mean Molecular Weight.
This figure is frequently quite useful for identification pur-
poses and for use in calculating the heat of vaporization. The
determination is made in a Beckman freezing point apparatus.
Commercial stearic acid previously standardized with a sub-
stance of known molecular weight or benzol may be used as
solvents. The operation is as follows :
The freezing tube A, with the stirrer and garnets, is care-
fully washed and dried, and from 15 to 20 grams of the sol-
vent accurately weighed into it. It is stoppered both at the
top and side tube and placed in the jacket tube B. The jar C
is then filled with a^freezing mixture (for benzol, water with
a small piece of ice is suitable).
The Beckman thermometer is adjusted so that the mercury
at the freezing point of the solvent (benzol = 5° C.) is some-
what above the middle point of the scale. The thermometer
is inserted in the perforated stopper holding the platinum
stirrer and after dropping in a few small garnets the ther-
mometer and stirrer are rapidly inserted in place of the stop-
per in the freezing tube. By this time the solvent should be
from i° to 2° below the freezing point. The stirrer is worked
up and down to cause the formation of crystals — as these be-
gin to form the thermometer rises and as it reaches the freez-
ing point remains practically stationary (vibrating a few
thousandths under the magnifying glass however) the mean
point is observed. The freezing mixture should be stirred con-
54
stantly and the solvent should be stirred at a uniform rate of
from 30 to 35 strokes per minute.
FIG. 7.
The freezing tube is removed and from 0.5 to 0.7 gram of
the substance is brought into the solvent through the side tube.
For oils a weighing pipette is useful, as the quantity must be
55
i
accurately weighed out. Care must be taken to allow the tem-
perature to rise until all crystals have disappeared but not
far enough to destroy the setting of the thermometer. The
freezing tube is replaced and when the substance has gone into
solution the freezing point is observed as before. The differ-
ence is the depression (t). Repeated additions of the solvent
may be made and the depressions noted. The depression (t)
should not be less than 0.5° and not over 3.0°.
If M = molecular weight of substance.
C = constant of solvent.
P — grams of substance per 100 grams of solvent.
t = depression of freezing point.
M CP
M =
t
The solvent should be standardized with a pure substance of
known molecular weight (naphthalene may be used with ben-
zol). If 20 grams of benzol were used and 0.5 gram naph-
thalene added, producing a depression of 0.986° we would have
M t 128 X 0.986
Constant = -=— ='— - = so. 48
P 0.5 X IOQ
20
Then assuming 19 grams of benzol used, 0.7 gram of oil added
and t = 1.195 we would have
cp (o 7 X IPO )
M = — = 50.48 X 19 = = 155
i 195
REFERENCES.— Z. phys. Ch., i, pp. 577, 631; 2, pp. 307, 491, 638, 964;
5, p. 94; B., 21, pp. 711, 860; 22, pp. 1430, 2501; 23, R i; 24, pp.
1431 ; 27, R 542, R 845, R 974.
Paraffine. — One hundred grams of crude oil are distilled
rapidly from a tubulated retort till the temperature of 300° is
reached. A weighed receiver is then put into position (with-
out a condenser) and all oil driven over until the residue cokes
completely (without thermometer) ; the amount of heavy oil
distilled is determined.
Five-tenths gram of the substance is dissolved at room tern-
56
perature in a mixture of ether and absolute alcohol (i : i) to
a clear solution, then cooling to — 20°, just enough alcohol-
ether mixture added till all oily drops are dissolved and par-
affine flakes are visible. With much paraffine, it is advisable
to warm with ether to complete solution and then add the
same volume of alcohol. The precipitated paraffine is then fil-
tered on a funnel surrounded with a rock-salt and ice-freez-
ing mixture, all traces of the alcohol-ether solution being re-
moved, and then washed free from oil by means of cooled
alcohol-ether. The residue is then washed into a weighed
glass dish with hot benzol, or naphtha and the solvent evap-
orated on a water bath.
The paraffine is carefully washed with cooled alcohol-ether
until 5 cubic centimeters of the filtrate on evaporation will
give no residue, or only a trace of material solid at room tem-
perature, is obtained; too prolonged washing is to be avoided
because of the still quite noticeable solubility of paraffine in
alcohol-ether. If on cooling, the paraffine is seen to be hard,
it is heated at 105° for 15 minutes and weighed after drying
in a desiccator; if the paraffine is soft (with melting point
under 45°), it should be dried several hours in a vacuum
desiccator at 50° before weighing.
Determination of Specific Gravity.
For control tests on the original sample, the specific gravity
may be taken with sufficient accuracy with a hydrometer.
The oil should either be brought to the normal temperature
15.5° C. or 25° C., or else the temperature observed and the
gravity corrected back to normal temperature.
Specific gravity at T = observed gravity at temperature
t° + (T — t x 0.009).
In determining the specific gravity of the fractions the
Sprengel tube type of pycnometer is recommended. The tube
is completely filled and is immersed in water at the normal
temperature for 15 minutes. The tube is tilted and the excess
material remove^! from the capillary with filter paper until the
57
liquid reaches the calibrated mark. The tube is then dried and
weighed.
Platinum or nickel wire should be used in suspending the
tube on the balance.
For a calibration of the tube made by weighing empty and
filled with water at the normal temperature the specific gravity
is given by the formula :
Weight filled with oil = weight empty
Specific gravity . . , — — — ^-r—
Weight filled with water = weight empty
While the former practice has been to determine specific
gravity at 15.5° C., the later standards of the American Society
for Testing Materials have very generally used 25° C. as the
normal temperature, and the use of this temperature is recom-
mended.
Specific Heat.
This determination is made with a Parr or bomb calorim-
eter, using the oil instead of water as a calorimeter liquid,
and burning a definite quantity of a pure substance such as
sugar or benzoic acid. Owing to the low specific heat of the
oil, the quantity to be burned should be roughly calculated,
using 0.45 as an assumed specific heat of the oil to secure a
temperate rise of not over 2.5°.
The operation is carried on exactly as described for deter-
mining the heating value :
(Grams substance X heating value) = ( Water equivalent X corrected rise \
( Weight of oil taken) X (Corrected rise)
Sulphur.
This determination is most conveniently carried out together
with the determination of the heating value in the bomb calo-
rimeter. After the combustion the gases are allowed to escape
slowly through a 10 per cent, solution of sodium carbonate
using about 20-25 cubic centimeters in a small beaker or test
tube.
The bomb is then washed out thoroughly with water, the
soda solution is added to the washing and the solution boiled
until the aluminum and iron are precipitated, filtered and
58
washed. The solution should have a volume of 70-100 cubic
centimeters — is accelerated with HC1 and precipitated in a
boiling solution with BaClg.
BaSO4x 0.1373 = S.
A METHOD BY ROTHE.
Three-fourths gram of oil with 1.5 grams of MgO and 30-
40 cubic centimeters of nitric acid (specific gravity 1.48) are
placed in a 250 cubic centimeter round bottom Jena flask.
Hood. After the first violent reaction, the flask is heated
gently for iJ^-2 hours in a sand bath, the liquid being kept
boiling gently. The excess nitric acid is then evaporated over
a free flame and the residue heated till the nitrates begin to
decompose. After cooling, 10 cubic centimeters concentrated
acid are again added. After 15 minutes heating, the mass is
evaporated to dryness, keeping the flask in constant motion,
then heated with a triple burner until the nitrates are com-
pletely decomposed. The residue is generally white ; by adding
10 cubic centimeters of hydrochloric acid (specific gravity
11.24) and heating, it is dissolved and then filtered after dilu-
ting with 20-30 cubic centimeters of water. In the filtrate, the
sulphuric acid is determined by precipitation with barium
chloride in the customary manner.
Water.
Small quantities of water may be determined in the course
of the distillation test. Should the water exceed 2 per cent,
it should be determined separately.
Water is quantitatively determined as follows :
About loo grams of oil (less if much water is present) are
distilled from an oil bath with toluol; this toluol should have
been previously saturated with water. Pumice is added to
avoid bumping. Eighty to ninety cubic centimeters are caught
in a cylinder constricted to a narrow graduated tube at the
bottom ( Hoffman-Mar cusson). After washing the inside of
the condenser with toluol and loosening any water drops on
the side of the cylinder with a stirring rod, the amount of
water can be directly read on the graduations.
59
TESTING OF PURIFICATION MATERIAL.
New Material.
The following determinations are covered in the analysis
of new oxide :
Weight per Bushel.
Sampling.
Moisture.
Metallic Iron.
Iron Sesquioxide.
Fouling Test.
Used Purification Material.
The following determinations are covered in the analysis of
used oxide:
Sampling.
Moisture and Light Oils.
Total Sulphur.
Soluble Sulphur and Tarry Matter.
New Purification Material.
WEIGHT PER BUSHEL AND SAMPLING.
These two determinations can conveniently be done in one
operation. The necessary apparatus are :
Bushel box, made of wood, the capacity to be 2,150.4 cubic
inches, approximate dimensions inside 12 x 12 x 15 inches.
Sampling tool made of brass tubing, 2 inches in diameter,
1 8 inches long, upper surface cut away to a length of about
15 inches, and rounded. A wooden handle is attached to the
other end. Fig. 8.
)G
,2"
• — ^
Section
FIG. 8.
Ordinary garden trowel.
The operations are as f ollowrs :
Samples are taken from a number of bags by thrusting the
6o
sampling tool into each bag in turn. The number of bags
sampled depends on the size of the lot of oxide received. It
should be at least 10 per cent, of the total number of bags.
For instance, if the lot contains 500 bags, a sample should be
taken from every tenth bag, or from 50 of the bags.
These samples are then thrown together on a clean surface,
mixed, and spread out to a depth of about 3 inches. Portions
are then taken over the surface at equal distances with the
garden trowel, digging down to the bottom when taking each
portion. These portions are thrown into the bushel box and
well mixed. Sufficient material is taken in this manner to
fill the box level with the upper edge. The box and contents
are then weighed. The weight of the empty box deducted
from this weight gives the pounds of oxide per bushel. The
contents of the box are quartered down and the sample finally
obtained put into a quart glass Mason jar, or a tin can with
air-tight cover.
CAUTION. — If the oxide contains metallic iron, it must be
mixed as little as possible consistent with obtaining a repre-
sentative sample, because the greater density of the iron will
cause it to pass to the bottom, thus interfering with the uni-
formity of the sample.
If the oxide is not shipped in bags, the operator must use his
judgment when sampling, bearing in mind that the portions
should be taken throughout the shipment in a uniform manner,
so that the final sample will be representative of the entire
shipment.
MOISTURE.
Weigh out 100 grams from the jar or can into a counter-
poised tin dish, on a balance accurate to o.i gram. Dry in an
oven at 100° C. for one hour. The loss of weight is reported
as moisture.
The dried sample is then ground in a coffee mill until it is
about 3o-mesh size, and quartered down until about 30 grams
are finally obtained. This final sample is kept in a tightly
6i
stoppered, wide mouth bottle, and used in subsequent deter-
minations.
Note. — The grinding is best done by first having the mill
set to grind coarsely, then repeating as many times as neces-
sary, adjusting the mill to grind finer each time. By this
method, usually, no difficulty will be found in breaking down
any iron borings that may be in the oxide.
METALLIC IRON.
Weigh one gram of the dried oxide from the bottle above
into a 100 cubic centimeter beaker and treat with 50 cubic
centimeters neutral, saturated solution of cupric ammonium
chloride, allow to stand with frequent stirring for at least
an hour in a warm place, when all particles of metallic iron
should be dissolved. Filter off the residue and wash free of
chlorides, and to the hot filtrate add ammonia in excess. The
iron will be precipitated as hydroxide, while the blue cupric
hydrate dissolves in excess. Filter off the precipitate, wash
with water containing a little ammonia until practically free
from copper salts.
Dissolve the precipitate on the filter with hot, dilute hydro-
chloric acid, i in 10, and wash free from HC1. To the hot
filtrate, ammonia is again added in excess to precipitate. The
precipitate is then filtered, washed, and ignited. Weigh as
Fe2O3. This weight multiplied by 69.94 gives the percentage
of metallic iron found.
Note. — This method must be regarded as only approximate.
It is, however, the best method the Committee has been able to
find. It gives low results, due to the oxidation of the iron
when the residue is being filtered from the cupric ammonium
chloride. The error varies with the percentage of metallic
iron present, being greatest when this percentage is low.
If large pieces of iron borings are present it is advisable to
remove them with a magnet, brush off the adhering oxide of
iron, etc., returning the latter to the sample to be analyzed.
The clean pieces are weighed and the percentage calculated
5
62
and added to the metallic iron found by the method described
above.
IRON SESQUIOXIDE.
Iron is usually present in an oxide in some form of hydrated
ferric oxide. It is not practicable to determine accurately the
state of hydration ; hence, it has been thought best to determine
and report the oxidized iron present as sesquioxide.
Dissolve 0.5 gram of the dried sample in 20 cubic centime-
ters (1:1) hydrochloric acid in a 100 cubic centimeter beaker,
evaporate to dryness, adding a few drops of nitric acid from
time to time. Take up with 5 cubic centimeters concentrated
hydrochloric acid, add 50 cubic centimeters hot water, boil and
filter. Wash filter well with hot water. To the filtrate, add 25
cubic centimeters bromine, water and heat to boiling. When
the excess of bromine has been driven off, remove beaker from
heat and precipitate the iron as hydroxide with ammonia. Boil
for five minutes; allow the precipitate to settle. Filter, wash
well with hot water, dry, ignite, and weigh as Fe2O3. This
gives the total iron in terms of Fe2O3. If metallic iron is pres-
ent, it must be determined by the previous method, and its
amount also in terms of Fe2O3 deducted from the total iron
as Fe2O3. The difference will be iron sesquioxide. This
weight multiplied by 200 gives the per cent, of iron sesqui-
oxide.
Alternate Method. — The residue obtained from the cupric
ammonium chloride solution in the method for metallic iron is
ignited in a platinum crucible until all carbonaceous matter is
destroyed and there remains only a mass of red ferric oxide.
Transfer as much as possible of this to a 100 cubic centi-
meter beaker, dissolve in 15 cubic centimeters to 30 cubic centi-
meters concentrated hydrochloric acid, at the same time dis-
solving from the crucible any adhering particles of ferric oxide.
When solution is complete, filter into a 250 cubic centimeter
graduated flask. Wash and ignite the residue in a platinum
crucible, and fuse with two grams of dry sodium carbonate.
Dissolve the fusion in hydrochloric acid, add this to the con-
tents of the 250 cubic centimeter flask, fill to the mark with
distilled water, and mix well. With a pipette, transfer 50
cubic centimeters to a 150 cubic centimeter beaker, add am-
monia to precipitate the ferric hydroxide, boil for five minutes,
allow to settle, and filter. Wash with hot water, dry, ignite,
and weigh as Fe2O3. The weight multiplied by 500 gives the
per cent, of iron sesquioxide.
FOULING TEST.
The fouling test of an oxide offers the best means for de-
termining its value for purification purposes.
A glass tube with a bulb at one end is most suitable to hold
the oxide to be tested, but a U-tube or almost any other tube
compact enough so that it can be weighed on analytical balance
will answer. (See C in Fig. 9.)
FIG. 9.
Five grams of the oxide to be tested are next mixed with
about 2 grams of coarse sifted sawdust and placed in the tube,
and covered with a layer of cotton to prevent any of the con-
tents from falling out at the stopper end of the tube. The
stopper is then inserted. The entire tube is accurately weighed
and the total weight noted. For sponge ore oxide already
mixed with shavings the sawdust is omitted. This tube is
followed by a U-tube containing calcium chloride and weighed
64
together with the tube holding the oxide. Another large U-
tube or a tower filled with calcium chloride to dry the hydrogen
sulphide issuing from the generator is connected with the test
tube by means of a piece of rubber tubing and the whole con-
nected with the generator. A small piece of glass tubing
closed at one end so as to leave only a hole the size of a small
pinhole and placed between the U-tube and the generator reg-
ulates the flow of gas.
The hydrogen sulphide gas generated in the Kipp generator
A, and dried by passing it through the calcium chloride in the
U-tube or tower B, is decomposed by the iron oxide in the
test-tube C, forming iron sulphide and water. The water
formed is absorbed by the calcium chloride in the second test-
tube D.
The test is carried on for one hour, after which time the test-
tubes are disconnected and weighed. The gain in weight repre-
sents the amount of hydrogen sulphide absorbed, or rather
decomposed, by the oxide. By dividing the amount of oxide
taken into this weight, the percentage of hydrogen sulphide
decomposed can be determined, and from the latter the sulphur
calculated.
Some oxides are very active at the first fouling (when new),
but revivification is slow and incomplete, and on second fouling
they give far lower results. For this reason it is sometimes
desirable to carry the test far enough to determine the total
absorbing capacity of an oxide.
After the first fouling, the oxide tube is disconnected from
the CaCl2 tube, and air passed over it until completely revivi-
fied. To prevent an oxide which has the tendency to revivify
very rapidly from getting too hot and consequently burning,
thus becoming more or less inert, it is advisable to pass the
air used for revivification over water so as to saturate it with
water vapor. For this reason it is not advisable to remove the
oxide from the tube for revivification, for it being very dry, on
direct exposure to air, any very active oxide is found to take
fire.
After complete revivification, the tubes of oxide and CaCl2
65
are again weighed and connected with the Kipp apparatus, and
fouled a second time. This second fouling as a rule is suffi-
cient to show how active the material is, for if the results of
the second fouling are very close to those of the first, the
material is very active, but the test can be repeated the same
number of times as the oxide is revivified in practice. Thus
the entire capacity of the oxide can be determined before it is
placed in service.
\
Used Purification Material.
SAMPLING.
Used purification material may be required to be sampled
under two conditions.
I. When removed from the box for revivification.
II. When revivified in the box.
When the oxide has been removed from the box and spread
out, portions may be taken to the entire depth of the bed with
the trowel at points situated at equal distances over the sur-
face. When about a bushel has been obtained, this is thor-
oughly mixed, quartered down, and a quart jar or can filled
and tightly closed.
When the oxide is revivified in silu, samples should be taken
in different parts of the box, the operator using his judgment
and endeavoring to obtain a sample which represents the entire
contents of the box.
MOISTURE AND UGHT OILS.
Weigh 100 grams of the sample from the jar or can into a
counterpoised tin dish. Place the dish in a drying oven, the
temperature of which is not allowed to exceed 95° C. For
coal gas oxide it is advisable to air-dry the sample for 5 to 10
hours in a warm place or drying oven kept at 55° C. Examine
occasionally by removing from the oven and allowing to cool.
It will be found that some oxides containing much tarry matter
require several days to dry.
When the oxide appears hard on cooling, the dish and con-
66
tents are weighed and a loss reported as moisture and light
oils.
The sample is then ground in a coffee mill to 3O-mesh fine-
ness, and quartered down until about 30 grams are obtained
which are kept in a well corked bottle for subsequent de-
terminations.
TOTAL SULPHUR.
Laboratory routine method, gravimetric or volumetric as
desired : Oxidation of Sulphur : — Mix 0.5 gram of the sample
in a 100 cubic centimeter nickel crucible with 5 to 10 grams of
sodium peroxide, depending on the sulphur content of the
oxide. Place the crucible in a water bath containing cold
water, attach a fuse by passing it through a slip in the edge of
the crucible, put on the cover, which must be weighted to pre-
vent it blowing off, and light the fuse. The fuse is prepared
by soaking a cotton string in a strong solution of potassium
nitrate and drying. Transfer the fused mass to a 500 cubic
centimeter beaker and dissolve it in cold water. Next, add
dilute HC1 (1:3), while stirring, until the iron precipitate co-
agulates in a flocculent form, but keep the solution distinctly
alkaline to avoid the solution of iron hydroxide. Heat to
boiling, filter off the precipitate and wash well with hot water.
Gravimetric determination of sulphur. — Acidify the filtrate
with dilute HC1, heat to boiling and precipitate with barium
chloride. Filter, wash and ignite as usual after two hours
standing.
Volumetric determination of sulphur. — Solutions required:
Barium chromate, 40 grams dissolved in dilute HC1, (80 cubic
centimeters HC1 specific gravity 1.2, 920 cubic centimeters
H2O,) approximate value of I cubic centimeter 0.04 gram
BaCrO4. Sodium thiosulphate, N/io, I cubic centimeter
equals 0.001066 gram of sulphur.
Method. — Catch the filtrate and washings in a 500 cubic
centimeter volumetric flask, cool, and dilute to the mark.
Transfer 100 cubic centimeters of the solution to a 200. cubic
centimeter volumetric flask, add 25 cubic centimeters of barium
67
chromate solution, shake for a minute and then add dilute
ammonia, a few drops at a time, until the color changes to a
pure yellow, indicating the complete precipitation of the ex-
cess of BaCrO4. Dilute to i cubic centimeter above the
200 cubic centimeter mark, filter through a dry filter paper
into a 100 cubic centimeter flask. Throw away the first part
of the filtrate. Transfer the 100 cubic centimeters of the
filtered solution to a glass stoppered bottle, acidify with 10
cubic centimeters HC1, add I gram of solid potassium iodide,
shake, and titrate the liberated iodine with N/io sodium
thiosulphate.
Multiply the number of cubic centimeters of sodium thio-
sulphate by 2.132; this gives the per cent, of sulphur in the
oxide.
Alternate method. — Weigh 0.5 gram of the oxide into a
300 cubic centimeter Erlenmeyer flask and treat it with 30
cubic centimeters of a mixture of 3 parts HNO3 and 2 parts
HC1. Heat gently and when the action ceases add a few crys-
tals of potassium chlorate, and boil. Add 20 cubic centimeters
HC1 and evaporate to dryness on a water bath. Heat in an
air oven to 110° C. for one hour to dehydrate silica. Next,
cool the flask, moisten the mass with 5 cubic centimeters HC1,
take up with 100 cubic centimeters of hot water, boil, filter, and
wash well with hot water. Dilute the solution to about 600
cubic centimeters and precipitate with barium chloride. Filter
after two hours standing, ignite, and weigh the barium sul-
phate in the usual manner.
SOLUBLE SULPHUR AND TARRY MATTER.
EXTRACTION WITH CARBON TETRACHLORIDE.
Weigh one gram of the dried oxide, wrap it in a 9 centimeter
filter paper. Place the paper and contents in a 10 cubic centi-
meter porcelain Gooch crucible, which is equipped with an
aluminum wire bail. Weigh the crucible and contents and sus-
pend from the hook of a Wiley- Soxhlet extraction apparatus,
as shown in Fig. 10. Fifty cubic centimeters of carbon tetra-
chloride are placed in the extraction flask, and the whole ap-
68
paratus is assembled and heated in a water bath. Boil the
water and continue the extraction until the droppings from the
Gooch crucible remain colorless for at least a half-hour. The
extraction will probably be complete in three hours. Remove
the crucible and contents to a drying oven and dry for one hour
or until no odor of carbon tetrachloride is apparent. Weigh
the crucible and contents. The loss in weight will be soluble
sulphur and tarry matter.
FIG. 10.
Pour the contents of the extraction flask into a 100 cubic
centimeter Erlenmeyer flask, and with a little fresh carbon
tetrachloride, wash out the former flask into the latter. By
means of a cork and bent tube, connect the Erlenmeyer flask
with a Liebig condenser and distil on a water bath. When the
carbon tetrachloride has been distilled off, add 30 cubic centi-
meters concentrated nitric acid, warm gently on a sand bath,
and add cautiously, at short intervals, potassium chlorate crys-
69
FIG. lOa.
tals, (in all about 2 to 3 grams). Boil off the nitric acid, add
dilute hydrochloric acid, and precipitate with barium chloride.
Filter, dry, ignite, and weigh the barium sulphate. The per
cent, of sulphur found is soluble sulphur, the weight of which
deducted from the weight of soluble sulphur and tarry matter
gives the latter.
Alternate Method Using Carbon Disulphide. — Proceed ex-
actly as when using carbon tetrachloride as described above,
taking care, however, to employ only pure, freshly distilled
carbon disulphide. When the Gooch crucible is removed from
the extractor, allow it to stand at room temperature until all
odor of carbon disulphide has disappeared before weighing.
Caution — Do not dry in an oven, because of the liability of
carbon disulphide to spontaneous combustion. Empty and
wash the extraction flask into an Erlenmeyer flask, using pure,
freshly-distilled carbon disulphide.
Distil off the carbon disulphide and remove the last traces
by means of a current of air applied to the gently heated flask.
Oxidize the contents with nitric acid and potassium chlorate
as above, and precipitate in hydrochloric acid solution with
barium chloride.
Note. — Extraction with carbon disulphide is liable to give
high sulphur results, due to the decomposition of the solvent
during and subsequent to the extraction. It is therefore neces-
sary to use only recently distilled carbon disulphide, and when
the extraction is finished to distil off and remove the last
traces as rapidly as possible. The Gooch crucible is used in-
stead of the usual extraction cup on account of the convenience
in weighing.
CHAPTER H.
GAS ANALYSIS.
The following determinations are covered in the analysis of
illuminating and furnace gas :
Benzol.
Illuminants.
Carbon Monoxide.
Hydrogen.
Methane.
Ethane.
Carbon Dioxide.
Oxygen.
Nitrogen.
Source of Method.
The method of determining benzol is that due to Pfeiffer,
published in Chemiker-Zeitschrift, 1904-28-76.
The other methods are those due to the paper by Mr. E. H.
Earnshaw, published in the JOURNAL, of the Franklin Institute,
September, 1898.
Sampling.
The method of sampling depends upon whether it is puri-
fied or unpurified under pressure or vacuum. In some in-
stances, it is possible to draw the samples directly into the
analyzing burette, but more often they must be transferred to
the laboratory in containers specially provided for the purpose.
The figures show two forms of gas sampling tubes in general
use.
The one shown in Fig n is provided with cocks, and is,
therefore, somewhat more convenient than the one shown in
the Fig. 12, which must be closed by sealing off the ends.
These tubes are very useful in taking a sample sufficient for a
single analysis, and in the great majority of cases, a tube of
this kind will be all the equipment necessary, provided the gas
is under pressure.
In taking a sample with the tube as shown in Fig. n, it is
first filled with water and connected to the gas supply by a
short piece of hose which, together with the connections, has
been thoroughly purged of air and dead gas. The water is
then permitted to run out ahead of the gas, after which the
outlet cock is closed ; then the inlet, which places the gas under
a slight pressure and lessens the liability of air being subse-
quently drawn in by a leakage at the cock.
FIG. 11.— Gas sampling tube— with stop cock
This may be further guarded against by dipping the ends of
the tubes in melted sealing wax, and, as an extra precaution
by placing sealing wax around the exposed portion of the
barrel of the cock. This serves the double purpose of pre-
venting the cock from leaking and also from being accidentally
turned.
FIG. 12. -Gas sampling tube for sealing.
In using the tube described in Fig. 12 the procedure is the
same, except that the end is temporarily closed by means of a
short piece of rubber tubing and a pinch cock, as shown in the
sketch, after the water has run out. The outlet to the tube is
then sealed off at the construction by means of a flame such
as that furnished by a gasoline torch or a Bunsen burner. A
candle flame may sometimes be used, but it is rare that the
glass is soft enough to make the operation easy. Having sealed
off the outlet, the inlet is closed in the same way without dis-
connecting from the gas supply.
When a sample is to be transported long distances or is to
73
be preserved for any great length of time before analysis, it is
far better to use sealing tubes, as there is no possibility of
leakage unless the end of the tube is broken, and this may be
largely guarded against by fusing the end to a blunt point or
turning it back upon itself. The tubes may be used repeatedly
and when the end gets too short, a short piece of glass tubing
may be sealed on.
It is sometimes desirable to collect a sample out of contact
with water. In this event, if there is an abundant supply of
gas, it should be allowed to flow through the dry tube for 4
or 5 minutes in order to displace the air, and then sealed as
described above. When the gas supply is small, mercury
should be used to displace the air.
Fig. 13.— Aspirator for large gas supplies.
If a large sample is required, the aspirator shown in Fig.
13 may be employed. This consists of a galvanized iron cyl-
inder with conical base and top having a capacity of about
1/2, cubic foot. The top is provided with a cock (A) and the
bottom with two cocks (B) and (C) as shown. The whole
apparatus is mounted on a suitable tripod or stand. It is used
ordinarily precisely as the tubes described above. When, as is
74
sometimes necessary, an average sample (of a run) for a
definite period is described, the cock B is set so that the water
will just run out in the stated time. The apparatus is then
filled with water and the cock C closed. When the apparatus
is connected and C is opened an average sample of the whole
run will be obtained.
Aspirating Tubes.
In sampling gas from services and moderate size mains and
connections, a fair average can usually be obtained direct
without the use of the aspirating tube. If, however, the gas
chamber or passage is large, as for example in a generator or
large sized main, such a tube must be inserted as currents are
always set up, and a sample taken simply through the shell
will not give a correct average. Even when a tube is inserted
to the middle of the chamber, it is difficult to get a true average
of the gas passing.
Glass aspirating tubes should be used when possible, as
they are easily cleaned and they do not act upon, nor are they
affected by, the gas passing through them. They may be used
in temperatures up to 600° C. (1,112° F.). L,ead tubes may
be used up to temperatures of 300° C. (527° F.) and are very
convenient as they are easily handled and may be bent into any
required position. For temperatures • higher than 600° C.
(1,112.° F.) porcelain tubes, platinum tubes, fused silica pipes
may be used, or water-cooled iron tubes. Fig. 14 shows a tube
which may be made from the ordinary fittings procurable
around a gas works.
The tube shown in Fig. 14 is made as follows :
A ^4-inch by ^-inch reducing socket is threaded through
from the inside to receive the end of a ^-inch pipe. Into
this socket is screwed a I Y^ -inch pipe threaded at both ends of
a length depending upon the desired length of the complete
apparatus. On the end of the I % -inch tube is placed a 1^2-
inch by i^J-inch bushing threaded from the inside and through
which the i^-inch pipe extends about 2 inches. A I % -inch
cross is screwed on the top of the pipe. One side of the cross
75
contains a ij^j- by a ^-inch bushing which carries a }/£-inch
nipple 3 inches long, the other side of the cross contains a
1 1/2 -inch by ^-inch bushing which carries a ^-inch nipple 3
inches long, a ^-inch L, on the inside of the cross and a piece
of y$ -inch pipe of such a length that it extends to within I
inch of the bottom of the i^-inch pipe as shown in sketch.
Fig. 14.— Water cooled sampling tube.
The pipe B, which consists of a piece of ^-inch pipe threaded
at one end, is passed through the top of the T and threaded
through the reducing socket. The top of the pipe is made
tight with the top of the cross 'by means of a lock nut or
stuffing box. When in use, the water supply is connected to
pipe C and the water overflows through the nipple B. The
complete apparatus, when in use, is held in place by means of
76
the bushing D. The sample of gas is obtained from the outlet
of the pipe B.
It is of very little use to provide branches to, or a slit in,
the aspirating tubes, as the currents are of less velocity near
the shell due to friction, and besides, with a slit pipe or one
drilled with holes, more gas will be drawn in near the sides
as the suction here is strongest. The best method is to set up
a strong primary current and take the sample from a second-
ary current at the side of the tube as shown in Fig. 15.
FIG. 15.— Method of supplying from large main.
Fig. 15 shows a glass tube inserted through a rubber stopper
into a i6-inch condenser connection. A glass or metal T is
fastened close to the end of the tube by means of heavy rubber
hose, and the sample is taken from the secondary current
flowing from A, the large primary current all the while flow-
ing from B.
The foregoing directions presuppose that the gas is under
pressure. If such is not the case, an aspirating apparatus
must be employed. For small samples the aspirating bulb
shown in Fig. 16 is recommended by analysts.
FIG. 16.— Aspirating bulb.
77
This consists of a small rubber bulb with valves working
opposite to each other, thus enabling it to work as a suction,
and as a pressure pump. In use, one end of the empty gas
sampling tube is connected to the gas supply, and the bulb is
connected to the other end, with the valves in such a position
that the pressure and relief on the bulb will suck the air out
and admit the gas. This should be continued for some time
to insure thorough displacement of the air. If there is no
objection to water coming into contact with the gas or if mer-
cury be conveniently used, a more satisfactory method is to
connect up as shown in Fig. 17 in which A is a glass or metal
FIG. 17. — Method of sampling from stack and breeching of boiler
aspirating tube, B a rubber tube, C the sampling tube. The
whole apparatus, including the hose and tube A, is filled with
water or mercury, and the tube introduced into the stack or
flue. Upon opening the cock on the sampling tube, the water
or mercury will flow out and the tube will materially increase
the pull.
Where running water is at hand, a water suction pump may
be used to advantage. There are many forms of these pumps
in use, but for durability and general adaptability for the pur-
pose, the "Chapman" pump shown in Fig. 18 is probably the
most satisfactory. By its use a strong primary sample may
be drawn off, and a secondary sample, taken from a side con-
6
nection as previously explained. A steam jet aspirator may
also be employed in the same way where high pressure steam
is available. It is shown in Fig. 19 and may be constructed
as follows :
FIG . 18.— Chapman filter pump .
The steam jet aspirator shown in Fig. 19 is made as follows :
Two 24 -inch nipples H and / are threaded into a ^4 -inch by
%-inch reducing tee A. H is left open for steam exhaust,
while on / is threaded a ^4-inch union D, a ^-inch pipe is then
threaded through a ^4 -inch by J^-inch bushing H, one end of
which has been hammered down to a point leaving a i/i6-inch
opening. The ^-inch bushing H is then threaded into the
union B and end of piece C connected to steam supply. A
l/4 -inch nipple is then threaded into the %-inch connection on
tee A and connected to place where sample is to be taken from.
Where it is necessary to take samples of crude gas, partic-
ularly crude coal gas for the determination of tar, or naph-
thalene, it is essential that the temperature of the gas be not
changed after the sample is withdrawn from the main. It is,
therefore, necessary that the sample tube be surrounded with
a water bath maintained at the same temperature as the gas
in the main. Tubes similar to Fig. 14 should be used for this
79
purpose, water at the proper temperature being supplied with
a water-jacket.
FIG. 19.— Steam or compressed air respirator.
Where crude gas is being sampled for its ammonia content,
a certain amount of ammonia liquor exists as a mist in the gas,
and at the same time, the walls of the main are also coated with
ammonia liquor. It is, therefore, necessary to arrange the
inlet of the sampling tube so that liquor collected on it from
the gas will flow into the sample. This is best secured by
placing an iron tube in the main approximately 83 per cent, of
the diameter from one side and inserting in this a slightly
smaller glass tube which will be inclined to the sample bottle
so that the ammoniacal liquor condensed in the glass tube will
be collected in the sample.
Volumetric Determination of Benzols.
The determination depends on the reaction
N02 4- 3SnCl12 + 6HCI = NH2 + 3SnCl4 + 2H2O.
The gas is treated in a glass stoppered separatory funnel of
a known content, the stopper and cork of which have been
lubricated with a drop of H2SO4, the gas is allowed to blow
8o
through the apparatus for 2 minutes, the stopper put in place
and the cock closed. The apparatus is disconnected from the
source of supply and the cock opened for a moment to insure
atmospheric pressure, the barometer and the thermometer are
read. Two cubic centimeters of a mixture of equal parts of
concentrated H2SO4 and fuming HNOa allowed to enter the
funnel by means of the lower tube, the cock closed, and a half-
hour allowed to complete the absorption of the benzol vapors.
Thirty cubic centimeters of a concentrated NaOH solution are
now added, and all the vapors set free are absorbed by shak-
ing. The solution is now neutralized with very weak HC1 ;
no indicator is needed, as the color of the solution as it changes
from an orange red of the alkaline state to a wine yellow of
an acid state, is all that is necessary. The solution is now ex-
tracted twice with 50 cubic centimeters of ether shaking 5
minutes each time; it is then separated from the other nitro
products and put into a flask containing I gram of potash and
y2 gram of finely powdered animal charcoal, which on shaking
and standing, takes out the strong yellow red coloration.
The solution is now filtered into a 200 cubic centimeter
graduated flask, and washed with absolute ether, which is
evaporated off on a water bath. As soon as this has taken
place, 10 cubic centimeters of absolute alcohol and about 10
cubic centimeters of a stannous chloride solution (150 grams
of tin dissolved in 50 cubic centimeters of HC1 and made up
to I liter) are added, and the flask warmed for 10 minutes on
the water bath. The flask is filled to the mark with water and
20 cubic centimeters are titrated with i/io N. iodine solution
and starch paste. A blank is run with 10 cubic centimeters
of SnCl2 solution, 10 cubic centimeters of alcohol, diluted to
200 cubic centimeters and 20 cubic centimeters titrated. The
difference between the two titrations gives the value of the
dinitro benzol and is calculated (b -- a) 10 x 0.0014 gram.
The percentage is calculated i gram dinitro benzol — 0.4643
gram C6H6, I gram of benzol = 279.2 cubic centimeters of
vapor of o° and 760 millimeters. The combined formulae
would appear as follows : J = volume of gas
8i
X
Vol. per cent. C6H6 = 0.4643 X 279.2
3690
x weight
of dinitro benzol or this can be simplified to read where b =
barometer, t = temperature, g = dinitro benzol and / = flask
content.
Volume per cent, of benzol = (36,090 + /) x g x (273 +
t + b).
It is now generally admitted that the accuracy of a gas
analysis made by direct absorption in a gas burette is not very
great, and that the applicability of the method is also limited
by the fact that only those absorbents which do not rapidly
attack rubber can be used. On the other hand it is claimed
that the time lost in connecting up absorption pipettes and in
passing the gas backward and forward is not compensated for
by the increased accuracy resulting.
The following apparatus was designed for the purpose of
meeting the above objection while retaining the essential feat-
ures of Hempel's method.
The burette as seen in Figs. 20-21 is similar to that described
in Hempel's Gas Analysis on page 28, except that a four-way
cock C replaces the three-way cock used by Hempel and the
burette is bulbed, thereby shortening the same and allowing a
finer graduation.
The capacity of the burette is about 105 cubic centimeters,
graduated in 1/20 cubic centimeter from 40 to 102 cubic centi-
meters. It is connected through the capillary tube D coming
out from the back of the cock C with manometer tube M.
The manometer is connected with the Petterson correction
tube R. A water jacket / surrounds the Petterson tube and
burette. A potash absorption pipette K which rests on the
adjustable stand S is connected permanently with the capillary
tube B.
This modification of Hempel's apparatus has the following
advantages :
82
i. It permits of the potash absorption pipette being per-
manently attached and so does away with at least five attach-
ments and disengagements of a piece of apparatus disagree-
able to handle, saving thereby considerable time and annoy-
ance ; for after both the explosion and combustion the gas can
be passed directly into the potash without stopping to connect
up any other pipettes. This is also true after the absorption
of illuminants by bromine and carbonic oxide by cuprous
chloride when it becomes necessary to remove the fumes of
bromine and hydrochloric acid.
FIG. 20.
2. With the apparatus constructed in the modified form the
two limbs of the manometer tube and the perpendicular por-
tion of the capillary tube coming out from the back of cock
C are in the same plane, so that you connect up the trouble-
some "sagging" of the manometer tube common to Hempel's
apparatus is overcome.
3. The bulbing of the burette make the apparatus much less
top-heavy and cumbersome and also permits of a much closer
reading, as the narrowed portion may be graduated to read to
1/20 cubic centimeter without trouble.
FIG. 21.
Besides the above important modifications, several minor
changes have been introduced which greatly reduce the time
necessary for an analysis, while not jeopardizing the accuracy
of the results.
The following pipettes and reagents are required for the
analysis :
A potash absorption pipette which is permanently attached
to the burette, as shown in sketch. (For reagent see page 125.)
A pipette filled with strong bromine water. In order that
84
this solution remain concentrated an excess of free bromine
is kept in the pipette.
A pipette for solids filled with stick phosphorus covered
with water.
A double U. G. I. absorption pipette. This combines in one
piece of apparatus the two solutions of cuprous chloride which
are necessary to remove the carbon monoxide.
A simple pipette filled with gas-saturated water for storage
purposes.
A mercury explosion pipette.
A U-shaped combustion tube containing about */2 gram
palladium black is also required.
The following is the method of procedure for an analysis of
a gas containing CO2, CMH8M, O2, CO, H2, CH4, C,H6> and N2.
Completely fill water jacket with distilled water.
Turn cock C so that the interior of the burette Y communi-
cates with A, open cock C, raise levelling bulb L, which has
been filled with gas-saturated water, until water flows out A.
Turn C so that interior of burette communicates with K, and
draw over potash solution to just above cock C.
Turn cock C so that Y communicates with D, and by raising
and lowering L and allowing air to escape through A, fill M
with water to N. Open C to A and by lowering L, draw in air.
Close C, raise L, open C to D, and admit air in M to C, and
close C.
Disconnect M momentarily at P and reconnect. The air in
R is now at atmospheric pressure.
Connect the tube containing gas sample with A, using glass
connector similar to one used on potash pipette, being careful
to displace with water all air that may be in connection. Open
C to A, lower L and draw in 100 cubic centimeters of gas.
Close C, raise L, open C to D, and allow gas to flow into M
until the water level is at O , and close Z. Take the reading on
burette after allowing a minute for water to run down off
the sides of the burette, add I cubic centimeter to observed
reading for the I cubic centimeter gas occupying space be-
tween O and cock C. Disconnect from sample tube or gas
85
supply as the case may be. Open C to B, raise L and allow
gas to flow into K, until the water from burette reaches the
bulbed portion of K, being careful to draw the I cubic centi-
meter from manometer and to force that into the potash like-
wise. Turn C to D and adjust water-level at N in M. Turn
C to B, lowrer L, and draw back gas until the potash solution
just reaches its previous position above C and close C. Raise
L and turn C quickly through arc of 180° so as to allow no
gas to flow back to B while turning cock so that the interior
of the burette communicates with manometer M. Raise L
until water in M is level with O, close Z and read burette,
adding i cubic centimeter to observed reading as before. The
difference between this reading and the preceding gives direct-
ly the percentage of CO2 in the gas.
Connect absorption pipette containing bromine to A resting
it on stand S, being careful as before to exclude all air from
connections. Open C to A, raise L, and force gas from the
burette into the pipette until water reaches the bulbed portion
of the pipette, drawing the gas from the manometer tube as
before, and close C. Shake the bromine pipette slightly until
gas is colored by bromine fumes, open C , lower L,, and draw
gas back into burette. Close C, raise L, C to B, and force all
gas immediately into potash. Close C to B, and open D, and
adjust water-level. Open C to B, lower L, and draw back gas
until potash assumes former position.
Close C, raise L, adjust water-level and read as before; the
difference between this reading and the preceding gives the
percentage of C,,H2,,. Disconnect the bromine pipette from
A and connect the phosphorus pipette.
Force the gas over the phosphorus as was done with the
bromine pipette, turn C to D, raise L and adjust water-level,
close C. If no white fumes are given off by the gas when
in the pipette it is a sure indication that all of the CMH2W>
compounds in the gas have not been completely removed. In
this event it is necessary to again pass the gas into the bromine
pipette. If fumes are given off, wait a minute or two to allow
them to partially condense, then open C to A, lower L, and
86
draw gas back into burette. Close C, raise L, open C to B, ad-
just water-level at O, and take reading. The difference between
this reading and the preceding gives per cent, oxygen present.
Disconnect phosphorus pipette and connect double absorption
pipette containing cuprous chloride, being careful to have all
capillaries filled with the solution. Open C to A, raise L, and
force all gas over one solution of cuprous chloride. Shake for
two or three minutes and then draw gas back into burette until
solution just passes cock on cuprous chloride, pipette, turn this
cock so as to connect with other solution of cuprous chloride,
raise L, and force gas over second solution to remove last of
carbon monoxide, and close C. Shake for a few minutes,
draw gas back into burette, and then immediately force it into
the potash pipette. Adjust water-level, draw gas back from
potash pipette and take reading.
The difference between this reading and the preceding gives
percentage of carbon monoxide.
It is important to notice that even with the precaution of
using two pipettes with freshly prepared cuprous chloride the
absorption of the carbonic oxide is seldom complete, usually
a trace remaining unabsorbed. However, this fact introduces
no error in the analysis, as this residue of carbonic oxide can
be determined by the combustion made to determine hydrogen.
The residue of the gas mixture remaining after the absorp-
tions may consist of the following :
H2 + CO + N2 + CH4 + C2H6, C3H8, etc.
For all ordinary purposes it is sufficient to assume that the
highest paraffine present is C2H6, as all others higher than this
exist only in traces.
There being no satisfactory known absorbent for any of
these gases, recourse is had to the method of combustion.
The analysis is accordingly continued as follows :
The double absorption pipette is replaced by the storage
pipette containing gas-saturated water. Pass approximately
15 cubic centimeters of the residue back into the potash by
opening Z, raising L and opening C to B. Turn C to A, and
87
pass remainder of residue into storage pipette. Close pipette
with a pinch-cock and disconnect. Adjust water-level in M
at N. Turn C to A and by lowering L, draw into the burette
about 85 cubic centimeters of air. Close C raise L and open
C to D draw the gas stored over the potash into the burette,
close C raise L, turn C quickly through arc of 180° to connect
with D adjust water-level at 0, close Z and take reading. The
increase over the previous reading is the amount of gas taken
for the explosion.
Connect mercury explosion pipette at A and pass mixture
of gas and air into pipette and explode, first partly withdraw-
ing glass connecting tube from rubber connection and placing
clip on same.
Adjust water-level in M at N, draw back gas from explosive,
pipette and measure contraction resulting from the explosion.
Pass the gas into potash, and the resulting contraction gives the
amount of carbonic acid formed during the explosion. Dis-
connect explosion pipette and connect phosphorus pipette.
Pass gas residue over phosphorus to remove all oxygen in ex-
cess of that which was required for explosion and measure the
amount of nitrogen left. This gives nitrogen introduced with
gas. By subtracting amount of air used for explosion X 79.2
from this reading, one obtains nitrogen introduced with gas
for explosion. This multiplied by factor obtained by dividing
the amount of gas residue taken for the explosion into the
whole amount of gas left after absorbing carbon monoxide,
gives the total nitrogen in the original sample of gas taken for
analysis. The percentage of nitrogen thus obtained should
check that obtained by subtracting the sum of the other con-
stituents in the gas from 100.
The equations obtained from the explosion are as follows :
(1) Contraction in volume = 3/2H2 + ^CO + 2CH4 -f-
2/2C2H,
(2) CO2 formed = CO + CH4 + 2C2H6.
(3) Residual nitrogen = N2 -(- N\.
Where N± is the nitrogen introduced with the air.
88
An examination shows that the equations I and 2 contain 4
unknown quantities and therefore two more equations are
needed for the solution. Fortunately, the method of frac-
tional combustion over palladium affords the needed informa-
tion. As is well known, when a mixture of hydrogen and CH4
with oxygen or air is passed over heated palladium black, the
hydrogen burns to H2O, but the CH4 remains unaltered. If
CO and any of the higher paraffines are also present, the CO
burns, but the paraffines do not.
Returning to the analysis, proceed as follows : Fill burette
to A by raising L, adjust water-level at N in M. Draw in
about 70 cubic centimeters air and measure it.
Connect storage pipette and draw in about 30 cubic centi-
meters gas residue, and measure, the increase in volume giving
the amount of gas taken for combustion.
Place explosion pipette with mercury level about one-half
up to capillary, on stand S, connect combustion tube to A and
explosion pipette, equalize pressure in combustion tube and
gas burette and re-measure gas in burette. Place combustion
tube in hot water by resting beaker containing water on T
and pass gas mixture backward and forward over palladium
until there is no, further contraction, measure gas and decrease
in volume gives contraction due to combustion of hydrogen
and carbon monoxide. The equations are :
(4) Contraction in volume = 3/2H2 -|- ^CO.
(5) CO2 formed = CO.
From these two equations, the value of hydrogen and CO
may be readily determined.
For the sake of simplicity, let us now assume that the same
quantity of gas residue was used in both the explosion and
the combustion.
We may then' subtract equation (4) from (i) and (5) from
(2), whence, designation the difference between the contrac-
tion due to combustion by the letter (a) and the difference in
the CO2 formed by the letter (b) we find
(6) 2 CH4 + 2-y2 CXT = *•
89
(7) CH4+ 2C,H~
whence (8) C2H7= ^ ~ 2
o
and (9) CH4 - ~
o
A very useful check on the accuracy of this determination is
obtained from the following :
Volume of gas taken for explosion = H2 + N2 + CO +
CH4 + C2H7 H2 + CO are found by (4) and (5), and AT is
given by (3).
Therefore, we have
(10) Volume taken = (H2 + N2 + CO) = CH4 + C2H6
and this value should be the same as the algebraic sum of (8)
and (9) or
(n) Volume taken + (H2 + N2 + CO) = 2a ~ b .
\}
This method if carefully pursued will give results that are
extremely accurate, and what is much to be desired, the method
is very rapid. Analyses have repeatedly been made in from
30 to 35 minutes.
The Modified Elliott Gas Analysis Apparatus.
This apparatus is shown in Fig. 22. It consists of three
glass tubes marked A, B, and C, mounted on an iron stand.
Tube A, called the absorption or laboratory tube, has a one-
way stop-cock, i, at the top, and three-way stop-cock at the
bottom, 2. The funnel, 3, is ground to fit the top of A, and
has two marks 10 cubic centimeters and 20 cubic centimeters
etched on the glass. The lower outlet of cock 2, drains to the
sink through a piece of rubber tubing. The side outlet is
connected with level bottle, 4, by another piece of rubber tubing
which is long enough to allow bottle 4 to be placed on the
shelf above the apparatus. There is a 100 cubic centimeter
mark near the lower end of A.
FIG. 22.
Tube, B, is called the explosion tube. It is graduated to
100 cubic centimeters in i/io of a cubic centimeter. It has a
three-way stop-cock, 5, the arms of which are connected to
tubes A and C by means of short pieces, of rubber tubing, the
connections being made by bringing the glass side pieces close
together and fastening the rubber with fine wire. The level
bottle, 6, is connected with the lower end of B by a rubber tube
long enough to allow the bottle to be placed on the shelf above.
The upper end of B has two platinum wires fused into the
glass. The electrodes are attached to these wires when the gas
is to be exploded. B is enclosed in a water-jacket which ex-
tends from the platinum wires to below the 100 cubic centi-
meter mark.
Tube C, called the residual tube, is a plain glass tube having
a one-way stop-cock, 7, and a level bottle 8. Connection is
made with B as described above.
REAGENTS.
Sodium hydroxide 10 per cent, solution.
Pyrogallic acid 10 per cent, solution, used by mixing in the
funnel with equal volume of 10 per cent, sodium hydroxide.
Acid cuprous chloride, made as follows :
Four hundred grams chloride dissolved in 1,800 cubic centi-
meters hydrochloric acid, (specific gravity 1.2) to this solution
add 400 cubic centimeters water. This solution is to be kept
in a bottle containing pieces of copper wire.
Fill bottles 4, 6, and 8 with water and place them on the
shelf above the apparatus. Open stop-cock i, turn 5 so that C
is connected with A. Then open 7, allowing water from bottle
8 to fill tube C and pass into A. Close 7 and turn 5 so that B
is connected with A, allowing water from 6 to fill B and pass
into A, then shut off 5. Turn 2 so that water from 4 fills A
and flows out at i, then close i. The apparatus is now filled
with water and the next step is to transfer the gas into it from
the collection tube. Before doing this, examine the apparatus
to see if there are any air bubbles imprisoned in it, paying
particular attention to the capillary tubes in the upper part. If
92
any bubbles are seen, drive them out with water from the level
bottles.
The sample of gas is transferred to the apparatus by remov-
ing funnel 3, replacing it with a piece of soft rubber tubing
which is filled with water, and attaching the collection tube and
passing the gas into A in the usual manner. When the gas fills
A to below the 100 cubic centimeter mark, cock i is closed and
the collection tube detached.
METHOD OF ANALYSIS.
Place the funnel 3 on the tube A. Set bottle 4 on the shelf
and bottle 6 on the table. Turn cock 5 to connect B with A
and turn cock 2 so that the gas in A passes slowly into B.
While the gas is passing into B, raise bottle 6 and hold it so
that its water-level coincides with the 100 cubic centimeter
mark on B, and at the same time regulate the speed of the
gas by manipulating cock 2. When the meniscus in B reaches
the 100 cubic centimeter mark, close cock 2, and without chang-
ing the position of bottle 6, reach up and close cock 5. Place
bottle 6 on the table and wait one minute to allow the water
adhering to the inside of B to run down, then raise bottle 6
bringing its water-level to that in B and verify the volume
in B.
Note. — If the transfer of gas from A to B is done very
slowly, it will be found that the water adhering to the inside of
B will all have run down at the same time that the meniscus
in B reaches the 100 cubic centimeter mark.
After making sure that there is a volume of 100 cubic centi-
meters of gas in B, place bottle 4 on the shelf, open cock i and
turn cock 2 so that the water in 4 will drive out the gas left in
A. Open cock 7 and allow the water from C to pass into A
driving out the gas left in the capillary tubes between B and A.
Close cocks 7 and i.
It will be noticed that there is a little gas above the zero
mark in tube B. This is less than i/ioth of a cubic centimeter
and may be ignored, or it may be compensated for during the
93
analysis by allowing the water from A to come only to the
cock 5 when gas is being transferred from A to B.
Place bottle 4 on the table and bottle 6 on the shelf, turn
cock 5 to allow the gas in B to pass into A. When the water
from B has reached the capillary above the bulb of A, close 5.
Do not allow any unnecessary water to flow from B into A.
Now pour 10 cubic centimeters of the sodium hydroxide re-
agent into the funnel 3, and slightly open i, allowing the re-
agent to pass into A. At the same time, manipulate I, and
give the whole apparatus a rotary motion on its base to spread
the reagent over the inner surface of A. Let the reagent enter
slowly and spread evenly. Use only 10 cubic centimeters of
this reagent; it is unnecessary and dangerous to use more, be-
cause 10 cubic centimeters will absorb about 50 cubic centi-
meters of CO2 and any excess is liable to absorb a few tenths
of a cubic centimeter of illuminants for every 10 cubic centi-
meters of the reagent. Close cock I when the reagent is near
the bottom of the funnel, and be careful not to allow any air
to enter tube A.
Open cock 5 slightly, allowing water from B to wash out
any reagent that may have crept into the capillary tubes be-
tween A and B. Place bottle 4 on the shelf and bottle 6 on
the table and drive the gas from A into B, shutting cock 5 when
the water from A reaches it. When the gas is back in B and
cock 5 closed, open cock i and turn cock 2 so that the water
in A will pass through its lower outlet into the sink.
When A is empty, fill funnel 3 with water and allow this
water to flow down and spread on the inside of A in the same
manner that the reagent was applied. This washes tube A clean.
While doing this, open cock 7 to allow water from C to wash
out the capillary tubes. Close cock 7, When A is thoroughly
washed, turn cock 2 to connect its lower outlet with bottle 4
thus washing out the rubber tube connecting A and 4. Turn
cock 2 so that its lower outlet connects with A, fill the funnel
with water and again wash out A. Turn cock 2 so that water
from 4 may enter A and when the water reaches the 10 cubic
centimeter mark on the funnel, close cock i.
7
94
Now take bottle 6 from the shelf and bring its water-level
to the meniscus in B, and carefully note the graduation on B
where the two levels coincide. Note the reading. This read-
ing subtracted from 100 will be the percentage of carbon di-
oxide, CO2 in the gas.
The above method of applying reagents, manipulating the
apparatus, excluding air and washing out and preparing for the
next absorption refers to all subsequent operations except the
following :
Illuminants are absorbed by adding 3 drops of bromine to
the water in the funnel and causing the bromine to enter A
very slowly and spread evenly, sodium hydroxide is then used
to absorb the bromine vapors.
Caution. — The bottle from which the bromine is taken
should never be lifted to the funnel 3, as serious accidents may
occur. This bottle should be on the table and the small quan-
tity needed removed by a pipette dropper to the funnel.
Oxygen is absorbed by a mixture of 5 cubic centimeters
each of the pyrogallic acid and sodium hydroxide solutions.
These are poured into the funnel from their respective bottles,
and well mixed.
Carbon monoxide is absorbed by 20 cubic centimeters of acid
cuprous chloride solution. This reagent must be added a little
at a time, waiting half a minute between each addition as its
action is slow. After absorption of CO place about 10 cubic
centimeters of water in the funnel and allow it to enter A,
spreading evenly and washing down the white salt. The ob-
ject of adding water is to absorb the acid vapors.
The residual gas consisting of hydrogen, methane and nitro-
gen is passed into tube C retaining 12 cubic centimeters in tube
B. Tube A is filled with air to the 100 cubic centimeter mark
and air is passed from A into B mixing with the 12 cubic centi-
meters of gas until the volume in B is about 72 cubic centi-
meters. This proportion is not absolute and must be found by
experiment as it varies for different gases. The above volume
is usually correct for carbureted water-gas. The excess air
in A is expelled, and the contents of B passed to and fro be-
95
tween B and A to thoroughly mix. When finally mixed the
volume in B is read, bottle 6 is placed on the floor and the gas
exploded by an electric spark. After waiting three minutes
the volume in B is read. The CO2 formed by the explosion
is absorbed by the sodium hydroxide, the gas is then passed
back to B and the volume again read. The oxygen remaining
in the gas is then absorbed by alkaline pyrogallol and the final
volume read.
The hydrogen, methane and nitrogen are calculated as fol-
lows : Let R be the residual gas, T the gas taken for explosion
(12 cubic centimeters), C the contraction after explosion. D
the CO2 absorbed. Then,
Hydrogen in T = 2C~4D (H T) ; Hydrogen in R =-H
Methane is T .= D; Methane in R =
T
D X R
The sum of all the constituents subtracted from 100 will give
the nitrogen. There are two methods of varifying the above
results :
1. Subtract the sum of the hydrogen and methane in T from
T, multiply this result by R and divide by T. This gives the
per cent, of nitrogen which should come within i/io of one
per cent, of the nitrogen found by difference. Expressed in
formulas this would be,
NT V R
T — (HT -f D) = Nitrogen in T. ^^~- ^Nitrogen in gas.
2. Multiply the air added by 0.791 ; this gives the nitrogen
in this air volume. Subtract this from the final reading; this
gives the nitrogen in T, (NT). Multiply this result by R and
divide by T. This gives the nitrogen in the gas. Expressed
in formulas this would be:
Volume i — T = air taken for explosion, (A)
A X 0.791 = nitrogen in A, (NA)
Final reading — NA = nitrogen in T, (NT)
NT X R
— = — = nitrogen in gas.
96
This result should agree within one per cent, of the nitrogen
found by difference. If all the calculations have been found
correct and a difference exists then this is due to the presence
of ethane. In this case the per cent, of nitrogen found by
method 2 is added to the sum of all the other constituents,
except methane, and the difference between this sum and 100
considered as methane.
The Morehead Apparatus.
This type of apparatus has been used for the past fifteen
years in the laboratories of The Peoples Gas Light and Coke
Company of Chicago, and by other large companies.
The gas analyzing apparatus as shown in Fig. 23 consists
of a graduated burette (4) fitted with platinum electrodes (13)
and a storage bulb (6). The three aspirator bottles (7, 8 and
9) with rubber tubing (14, 15, 16 and 17), and an electric
sparking outfit are also required. Both glass pieces are fitted
with three-way cocks (i, 2 and 3). The measuring, explosion,
washing, and the entire analysis is made in the graduated,
burette; the bulb (6) is used only for storage of the reserve
supply of gas after the CO absorption in case the explosion is
unsatisfactory. The burette (4) is usually provided with a
water-jacket (n) consisting of a large glass tube confining
by large rubber stoppers at the ends clear distilled water. A
bottle or beaker (10) is placed under cock (2) to form a seal
and catch waste reagents and wash water. A removable fun-
nel or cup (5) is attached to burette capillary tube at the top
by a ground joint. A secondary funnel (12) beneath (5)
serves to drain away excess reagent or wash water by means
of drain tube (18).
In preparing the apparatus for an analysis, first fill the as-
pirator and seal bottles (8, 9 and 10) and the levelling bottle
(7) with distilled water previously saturated at the tempera-
ture of the water- jacketed buretted with the gas to be analyzed,
and place aspirator bottles (7, 8 and 9) on shelf (21). By
manipulating cock (3) displace all air from rubber tubing
(15, 1 6 and 17) until water entirely free of bubbles flows up-
97
ward through ground joint into cup (5). Then open cock (2)
to seal bottle (10) and purge all air out of tube (14) through
FIG. 23.
cock (2) into seal bottle (10). Similarly open cock (2) to
burette (4) and fill same with water up to funnel. When the
apparatus is quite full of water, as described, remove cup (5)
98
open cock on sampling can or pipe from which the sample is
to be taken, allow gas to blow through the hose for a few
seconds to insure the explosion of all air, and then attach
hose to the ground joint end of the capillary tube at the top of
the burette. Turn cock (2) so that the water in burette (4)
communicates with the levelling bottle (7), held level with fun-
nel (5). Now open cock (i) so that the gas sample enters
burette only, and as the surface of water in the burette (4)
is depressed, slowly lower the levelling bottle (7), keeping the
surface of water in same slightly above that in the burette in
order to insure no inward leaks of air through loosely attached
tubing, etc. When the gas has displaced nearly all water to
about a point (19) in the burette, close cock (i), remove
rubber tubing at top of burette and replace cup (5). Open
cock (3) for a few seconds and expel gas from capillary tubes
until water flows into cup (5) and fills it about one-quarter
full. If the sample is taken from the house piping, or where
there is an abundant sample, it is well to allow the gas to flow
entirely through the burette and out at the lower stop-cock for
a few seconds, care, of course, being taken to purge out excess
gas from stem of cock (2) into bottle (10) before securing the
100 cubic centimeter sample for analysis.
If the gas sample be at a different temperature than the
burette, allow it to remain in the burette for a few minutes
before proceeding to secure the desired 100 cubic centimeters.
When the gas has assumed the temperature of the burette, raise
levelling bottle (7) so that the water-level is sufficiently above
the 100 cubic centimeter graduation of the burette to force
small bubbles of the confined sample through the water into
cup (5), when the cock (i) is slightly opened. Bubble excess
gas sample slowly outward in this manner until closing cock
(i) and lowering bottle (7), its water-level and that in the
burette are at the 100 cubic centimeter mark. If the zero
mark of the burette be at the cock (i), then the 100 cubic
centimeter mark is taken for a levelling point as just described,
but if the zero graduation be at the point of capillary retention,
where the capillary tube immediately below cock (i) widens
99
into the burette proper, then excess gas is bubbled outward,
until the water-levels in the bottle (7) and burette (4) are at a
mark equal to 100 cubic centimeters, minus the previously de-
termined volume (usually 0.3 or 0.4 cubic centimeter) of the
capillary tube between cock ( I ) and the zero graduation at the
point capillary retention. In the latter case, after adjusting
the burette water-level a 99.7 or 99.6, as the case may be,
bottle (7) is placed on a level with (10) and the cock (i) is
slightly opened until the water in cup (5) slowly enters the
burette capillary tube at the top to the point of capillary re-
tention, when it will be found upon raising bottle (7) that the
water-level corresponds with the one in the burette, which will
be at the 100 cubic centimeter graduation.
When there is just 100 cubic centimeters in the burette the
analysis may be started.
Turn the cock (2) so as to connect the burette with the
bottle (10) raise the funnel (5) until it is just off its ground
joint and drain, leaving about Y^ inch of water in the bottom.
L/ower the funnel onto its seat and put into it about 20 cubic
centimeters of potassium hydrate solution. Be sure that cock
(2) is set so that the burette is connected with (10). Now
open cock (i) and let the potassium hydrate solution drain
very slowly into the burette. When it has nearly all gone into
the burette close cock (i) and open cock (3) and let water
from bottle (8) or (9) through into the funnel (5) for about
ten seconds. Rinse the funnel and fill it with about 50 cubic
centimeters of distilled water previously saturated with the gas
being analyzed. Pass this wash water slowly through the
burette. Then turn cock (2) so that burette is connected with
bottle (7), and read the contraction of the gas, at the same
time holding the bottle (7) with the surface of the water in
the bottle, level with the surface of the water to the burette;
also note the reading on the burette graduations coinciding
with the bottom of the meniscus of the water-level in the
burette. The amount absorbed as indicated by the contraction
in cubic centimeters, or difference in cubic centimeters, be-
IOO
tween the 100 and the burette reading, equals the per cent, of
carbon dioxide.
Turn cock (2) to connect the burette with the bottle (10),
and with a I cubic centimeter pipette put about two drops of
bromine into the funnel (5) which should contain about 20
cubic centimeters of distilled water. Drain this slowly into
the burette, as in the previous operation, until the entire gas
space in the burette is filled with reddish brown bromine
fumes, then admit the rest of the bromine and most of the
water in the funnel. Next pour into the funnel about 30 cubic
centimeters of potassium hydrate solution and drain part of
this solution in slowly until the water ceases to rise and the
burette and the surface of the water are quite free from
bromine fumes. Wash with about 75 cubic centimeters of
aerated distilled water. Wait two minutes and measure as
explained above. The amount absorbed in cubic centimeters
equals the per cent, of illuminants.
Now place in cup (5) about 20 cubic centimeters of pyro-
gallic acid solution, and add 20 cubic centimeters of KOH
solution and allow mixing to take place naturally for about
ten seconds, then drain this through, wash out the burette with
about 75 cubic centimeters of distilled water and measure in
the way previously explained, after waiting at least two
minutes for gas to resume temperature of burette jacket. The
resulting contraction in cubic centimeters equals the per cent,
of oxygen.
Next place about 40 cc. of copper monochloride solution in
the funnel and drain through very slowly until no further
contraction is observed. Then if no reagent remains in cup
(5) add 10 cubic centimeters of same reagent and pass it
through the burette. Pass in about 50 cubic centimeters of
distilled water and after this 10 cubic centimeters KOH solu-
tion, drain through and wash out with about 100 cubic centi-
meters of distilled water. The amount absorbed in cubic centi-
meters equals the per cent, of carbon monoxide. This re-
agent should be added rather slowly and several minutes al-
lowed for its action on the CO.
IOI
The carbon monoxide is the last constituent to be deter-
mined by absorption. Of the remaining three, two must be
determined by an explosion and the third by difference.
Make a careful note of the reading of the burette after the
CO absorption, as this figure has to be used in the H2 and CH4
calculation.
Turn cock (2) so as to give connection between bottle (7)
and burette, cock (3) so as to connect (7) through burette
(4) and bulb (6) with (8). Place (8) on the table level with
(10) and hold (7) so that its water-level is opposite the gradu-
ation indicating 10 cubic centimeters. Now open cock (i)
carefully and allow gas to pass very slowly through cocks ( I )
and (3) into the storage bulb (6). When all but exactly 10
cubic centimeters has passed into the bulb (6) close cocks (i)
and (3) and place bottle (7) on a level with (10). Pass a
little water from (9) directly into the cup (5) so as to get all
of the gas out of the passages between the bulb (6) and the cup
(5). Also open cock (i) slightly and allow water to pass
from cup (5) into burette to zero mark. By manipulating
(7) have the amount of gas in the burette exactly 10 cubic
centimeters. A small excess may be gotten rid of through
cock (i) and the funnel (5). Turn cock (2) so as to connect
burette (4) and bottle (10); remove funnel (5) and connect
oxygen hose to top capillary tube. Then open cock (i) and
let about 20 cubic centimeters of oxygen enter. Remove oxy-
gen tubing and allow about 10 cubic centimeters of air to enter
burette; exact proportion of oxygen and of air admitted to
burette are not essential. Close cock (i), allow water to pass
from (9) through (3) and (i) into cup (5), and with bottle
(7) lowered, open cock (i) until water passes into burette to
zero mark. Then read contents of the burette accurately.
The quantity of the mixture in the burette should be in the
neighborhood of 40 cubic centimeters. Attach wires to the
electrodes on the sides of the burette, turn cock (2) so that the
burette is connected to the bottle (7), see that tubing is straight
and cause a spark to pass between the electrodes. After the
explosion allow the gases to stand at least three minutes before
102
reading the burette. Measure the contraction. This contrac-
tion is known as the "ist contraction." Make a note of this,
then place about 20 cubic centimeters of potassium hydrate
solution in the funnel (5) and drain the burette. Wash with
about 100 cubic centimeters of air saturated distilled water
and measure. The contraction due to absorption by the KOH
solution is known as the "2nd contraction." The amount of
gas left after the absorption for CO, divided by the amount
taken for the explosion is called the "constant."
The amount of hydrogen in the original mixture is equal to
the first contraction multiplied by two, minus four times the
second contraction divided by three and multiplied by the
constant.
FORMULA FOR H2
Per cent, by vol. of H2 =
2 X (ist contraction) — 4 X (2nd contraction)
— X constant.
3
Per cent, by vol. of CH4 = 2nd contraction X constant.
The constituent which we call "methane" — CH4 — often con-
tains in addition ethane — C2H6 — especially in rich gases and in
natural gas from wells which are approaching exhaustion.
The ethane present is burned to the explosion and is re-
ported as methane increasing the per cent, of methane slightly,
and lowering to the same extent the percentage of hydrogen
and of nitrogen.
It may, however, be readily determined separately if it is
desired. The hydrogen must first be separately absorbed by
means of a palladium tube. This is done by adding to 10 cubic
centimeters of the residual gases oxygen and air just as
directed above for explosion.
The palladium tube is installed between the burette and the
storage bulb. A beaker containing water, which is kept at the
boiling-point by a Bunsen lamp, is so placed as to have the
loop of the tube immersed in the hot water. An accurate
reading of the amount of mixture is then taken and the mixture
passed very slowly through the tube into the storage bulb and
103
then back. Care must be taken not to pass the gas through the
tube too rapidly, or the heat generated is apt to break up some
of the methane. The palladium does not really absorb the hy-
drogen from the mixture, but by a catalytic action causes it
to combine with the oxygen present and form water, and hence
two-thirds of the contraction due to passage of the mixture
over the palladium is the percentage of hydrogen. The known
volume of mixture after the hydrogen absorption is then ex-
ploded and the contraction noted.
A second contraction due to the absorption of the carbon
dioxide by KOH formed is also noted.
The volume of the methane and ethane may then be cal-
culated from the following formulae ;
First contraction, due to condensation of water formed, and
Second contraction, due to the absorption of carbon dioxide
formed,
Per cent, by vol. of CH4 =
4 X (ist contraction) — 5 X (2nd contraction)
X constant.
3
Per cent, by vol. of C2H6 =
4 X (2nd contraction) — 2 X (ist contraction)
- X constant.
O
The difference between the sum of all the percentages found
by the above determinations and 100 is the percentage of nitro-
gen.
GENERAL NOTES FOR ANY TYPES OF APPARATUS.
SOLUTIONS.
i. The potassium hydrate, or hydroxide solution, is made by
dissolving 5 parts by weight of chemically pure potassium hy-
droxide (purified sticks) in 100 parts by weight of distilled
water. This solution should be kept in well stoppered bottles
using rubber stoppers to prevent sticking and deterioration of
solution due to absorption of carbon dioxide from the air.
The same hydrate solution is used for the absorption of CO2,
of bromine fumes and with the pyrogallic acid for oxygen, and
IO4
of CO2 after methane. The hydroxide which comes marked
"Pure by Lime" is better for this use than that marked "Pure
by Alcohol."
2. The pyrogallic acid solution is made by dissolving 10
parts by weight of chemically pure pyrogallic acid in 100 parts
by weight of the above hydrate solution. To every 1,000 parts
by weight of this solution add 5 parts by weight of oxalic acid
as a preservative.
Do not mix the pyrogallic acid solution with the potassium
hydrate solution except in the funnel and until quite ready for
use, as the potassium pyrogallate thus formed will absorb
oxygen from the air and lose its strength. At least two min-
utes should be given the oxygen absorption with potassium
pyrogallate when flue gases or engine exhaust is being analyzed.
3. The copper monochloride solution is made by dissolving
75 parts by weight of chemically pure copper monochloride
in 720 parts by weight of concentrated hydrochloric acid, to
which has been added 400 parts by weight of distilled water.
Ten or twenty grains or more of clean bare copper wire or
foil should be added and kept constantly in the bottle with the'
mixture to prevent deterioration. When a small quantity of
the solution is added to a large amount of water a cloudy
white precipitate of copper monochloride appears. When no
cloudiness is thus produced, and the mixture shows a blue
tint, the preparation has become oxidized and is unreliable.
4. Gas-saturated distilled water may be prepared by passing
gas through the water at a temperature not less than, and
preferably a few degrees above, that at which it is to be used
so as to avoid evolution of the dissolved gases in the burette.
5. Distilled water may be sufficiently aerated by shaking it
vigorously for two or three minutes in a large bottle three-
quarters full of distilled water.
APPARATUS.
6. The apparatus may be cleaned from time to time by run-
ning through it a solution of potassium bichromate in sul-
phuric acid. This is useful, when the platinum points become
coated with carbon. This cleaning solution should be used
with care, as sudden mixing of the sulphuric acid solution with
the water in the burette generates considerable heat which may
break the burette.
7. For constant use it is well to install the water-jacketed
burette by means of clamps attached to a permanent pipe stand
supporting shelf over a sheet lead drain. The electrodes
leading from burette are insulated from the water-jacket by
rubber tubing, containing copper wires fused to the platinum
leads and leading to the terminals of a %-inch spark coil,
operated by at least two ordinary dry batteries. A drain fun-
nel connected by rubber tubing to a glass tube of ^-inch bore
extending to sink or drain pipe, will be found of great con-
venience in a permanent installation for getting rid of waste
from funnel or cup. A drain tube leading from bottom of the
seal bottle upward and curved in a semi-circle at the top so
that the outlet is level with the desired water-level in the bottle
will be found advantageous in securing cleanliness.
8. Rubber tubing should be of the heavy- wall, pure gum
variety, and of such internal diameter as to give tight joints
over the glass tubing, etc. The joints should be wired to in-
sure freedom from leaks incident to loosely attached tubing.
9. By keeping the apparatus and all of the bottles filled with
water, especially when not in use, and the reagent bottles in
immediate proximity, the entire outfit acquires about the
temperature of the room, and the error arising from the source
of temperature in the sample is eliminated.
10. The explosions take place in the explosion burette. A
coil which will give a ^4 -inch spark is ample. Too strong a
spark is apt to crack the glass as is a continuous play of sparks
between the points, or a play of sparks when the burette is
dry. If the explosion does not occur simultaneously with the
first spark, the spark need not be continued. Something else
is wrong. The usual trouble is that the confined mixture is
not an explosive one and the proportion of air or oxygen to
gas residual must be changed.
11. The reagent funnel and top ground joint of burette
io6
should be washed well after the completion of each analysis
to prevent sticking at the ground joint, due to any potassium
hydrate solution which may be present. This rule is applicable
also to other movable parts such as cocks which are likely to
stick.
12. The bulb which is not graduated, or an extra pipette is
used to hold the excess of gas when the explosion is being
made. The analyst occasionally loses an explosion, and were
it not for the gas thus held, the entire analysis would have to be
made over. By putting into the bulb all of the gas that is
left after the CO absorption, except the 10 cubic centimeters
which is used for the explosion, several explosions may be
made as checks on one another, or in case the first one is lost.
13. If the cocks stick, they can usually be loosened by a
little hot water on the outside. They should be kept well lu-
bricated with a mixture of equal parts of vaseline, tallow and
paraffme.
14. For getting samples, it is best to get four sample cans.
The sketch above will show what these are. In getting the
sample the can is placed in an upright position and filled quite
full of water, perfectly saturated with the gas to be sampled
in order to expel all of the air. A tube connected with the
upper stop-cock is then introduced into the space from which
the gas sample is to be drawn, and the lower stop-cock is
opened, allowing the water to run out and thus the sample
is aspirated into the can.
In drawing samples from places which have a suction in-
stead of a pressure, such as the inlet of an exhauster, or at
the base of a stack, or in the breeching of a boiler, the water
should be allowed to flow through a U-shaped glass tube
attached by a piece of rubber hose to the lower stop-cock. If
this is not done, after the water is all out, air will enter and
spoil the sample. It is essential to draw out all of the water,
even if only a small sample is required, as a number of the
constituents, illuminants and CO2, for example, are soluble in
water. If the gas to be sampled is under pressure it is well
enough to allow it to flow through the can for a few seconds
after all of the water has run out.
To get the sample out of the can, the lower stop-cock is
connected by a hose with a source of water under pressure
such as an aspirator bottle filled with water and placed at a
level above that of the sampling can, and as the water runs
into the can the gas will be displaced and may be led by means
of a hose to the burette.
15. The principal precaution necessary in gas analysis is to
see that the temperature of the apparatus and of the water
used, and of any additional water which may be used as well
as the temperature of the sample undergoing examination, does
not change during the analysis. A change of 5.2° F. will
cause a change of about I per cent, in the volume of any gas
at an ordinary temperature of 60° F. The temperature at
which an analysis is made is immaterial but that temperature
MUST remain constant.
16. In reading the burette, hold levelling bottle front and
just to one side of the burette, so that the eye of the analyst
can sight along the under surface of the water-level and bring
it in the same horizontal plane with the bottom of the meniscus
in the burette.
Analysis. — The quantities of reagents and wash water d£-
scribed in the foregoing method of analysis are intended main-
ly for the analysis of carbureted water-gas, henc^n the analy-
sis of any other gas the quantities specified should be changed
if it is found to be necessary in order to insure complete ab-
sorption of the various constituents. This is also true of the
oxygen and air required for explosion.
1 8. Introduce potassium hydrate solution slowly for first
absorption as the tendency otherwise is to secure too high a
percentage for the carbon dioxide.
19. Care should be taken in handling bromine. Keep it al-
ways under water, and do not allow it to come in contact with
the skin. Bromine is an exceedingly energetic reagent and
will cause painful chemical burns. If bromine fumes are
breathed, relief from the irritation caused to the throat can be
loS
obtained by inhaling alcohol or steam. The slick feeling caused
by getting potassium hydrate on the hands may be removed by
a little dilute hydrochloric acid.
20. The absorption of illuminants by bromine is a heat pro-
ducing reaction, and the increased temperature is apt to cause
the sample to expand unduly and may cause the loss of a part
of the sample by forcing it out through the cock and thus
vitiate the analysis. If it is seen that the expansion is becom-
ing excessive a little water may be added. The bulb at the
lower end of the Morehead burette is provided for this con-
tingency. In the analysis of acetylene, which contains over
90 per cent, of illuminants, this is especially apt to occur. If
the percentage of illuminants is high, it is well to admit a
little water during the absorption with bromine to restore the
normal temperature of the gas.
21. Twenty cubic centimeters of potassium pyrogallate solu-
tion when mixed with 20 cubic centimeters of potassium hy-
drate solution produce a rise in the temperature of the mix-
ture of about 5° F. over that of the original solutions. The
heat gained by the gas in the burette due to this cause should,
be taken into consideration and sufficient time allowed the
burette gases to resume initial temperature before reading,
^his solution should be passed into the burette very slowly, as
the absorption of oxygen is rather sluggish. The absorption
may be cor^kiered complete when no further discoloration to
purple or brown occurs upon introduction of the clear reagent.
22. The absorption of the last traces of CO is attended with
difficulty, and hence the analyst should be careful to add
sufficient copper monochloride solution and allow plenty of
time for the complete absorption. The reagent being strongly
acid, about 10 cubic centimeters of potassium hydrate solution
should always be added, after passing in about 50 cubic centi-
meters of wash water to insure removal of all fumes of hydro-
chloric acid and followed with the customary wash water.
23. When carbureted water-gas is being analyzed, double
quantities of residual gases, oxygen and air may be taken for
the explosion in order to secure higher accuracy.
109
24. Prior to all explosions, sufficient time (at least two min-
utes) should be allowed for the gases to thoroughly diffuse
through the oxygen and air added so as to give a homogeneous
explosive mixture and insure the combustion of all the oxidi-
zable gases.
25. No special care need be taken in measuring the amount
of air, or of oxygen added for the explosion, though the
amounts taken should not be less than those stated in the
"Method." Care must be taken, however, to measure accu-
rately the amount of gas taken for the explosion, and the total
amount of the gas, air and oxygen just before the explosion.
26. Air is added to the mixture to be exploded merely to
lessen the jar.
If the gas is very poor, or contains large quantities of nitro-
gen, no air need be added, and on the other hand if the gas is
quite rich, no oxygen need be added, air being sufficient, al-
though if oxygen is available it is best added to insure combus-
tion. With extremely poor gas such as blast-furnace gas and
the like, no explosion will take place even when oxygen is used
and no air added. Oxyhydrogen gas may be necessary, in
such cases. This is made by the electrolysis of water slightly
acidulated with sulphuric acid. Five to ten cubic centimeters
of the oxygen and hydrogen mixture added in addition to the
oxygen will always insure an explosion. As it recombines to
water, no special reading or note of the volume added need
be made.
27. Use only C. P. chemicals.
28. Never allow the funnel to become entirely empty; al-
ways keep about j^-inch of water or other liquid in the bottom
to prevent the suction of air into the burette.
29. In acetylene, flue gas, engine exhaust, air and gasoline
gas, there is no hydrogen or methane, and hence the analysis
need not be carried beyond the absorption with copper mono-
chloride for CO, and the oxygen tank or apparatus, the elec-
tric coil, batteries, etc., need not be provided. In analyses of
these gases the sum of the first found contractions subtracted
from 100 gives the percentage of nitrogen.
8
no
30. Where analyses are to be made, or where dispatch is an
important element, it will be more satisfactory to obtain a
cylinder of compressed oxygen for use in the hydrogen and
methane determinations, but where the apparatus is to be
moved from place to place, or is to be used only occasionally,
or where the analyses are confined for the most part to gases
which do not contain hydrogen or methane, such as flue gases,
acetylene, air, engine exhaust, etc., a cheaper and quite satis-
factory substitute can be had in a small retort by means of
which oxygen can be generated on the spot as needed.
To generate oxygen this retort is filled not more than half
full with a pulverized thoroughly mixed charge of potassium
chlorate and manganese dioxide in the proportions of 20 of
the first to i of the latter by weight. This is heated gently
over a Bunsen lamp. The evolution of oxygen begins at once
and it may be led to the burette by means of a rubber tube.
As 100 grams of potassium chlorate will produce 27,000 cubic
centimeters of oxygen and only about 20 cubic centimeters of
oxygen are used for one analysis, a very small spoonful of the
mixture will suffice for a great many explosions.
31. The method of analysis is so laid out that each deter-
mination must be made in its turn. With the exception of
the absorption of CO2 with KOH, and possibly that of CO
with cuprous chloride, no isolated determination of any one
constituent can be made with anything approaching accuracy
without starting at the beginning and making all of the ab-
sorptions down to that constituent.
Careful readings of the burette should be taken before and
after each determination, and especial care should be taken in
making the analysis to thoroughly absorb each constituent in
its turn. Partial absorption, or errors in the readings, will
not only introduce an error in the percentages of the constit-
uents in question, but the remaining portions of this constit-
uent will effect the latter determinations in the analysis and
thus have a doubly vitiating effect upon the accuracy.
Any CO2 left after the first absorption will be absorbed by
the KOH following the bromine and will be reported as illu-
Ill
minant or if by chance it is not absorbed by the KOH follow-
ing the bromine, it will be absorbed by the alkaline pyrogal-
late solution used for oxygen absorption and will appear as O2.
Any illuminant not absorbed will remain and burn to ap-
proximately 3^ times its volume of CO2 when the explosion
is made and will appear as CH4. A very small proportion of
illuminant left and burned and calculated to CH4 will be
sufficient to run the total of the analysis to more than 100
per cent. Any bromine vapors left after the absorption with
bromine will be absorbed by the pyrogallate solution and will
be reported as Oe.
Any unabsorbed CO will be burned to CO2 in the explosion,
H2 and CH4, and increase the percentage of N2 to the same
extent.
Any unabsorbed O2 left would decrease the percentage of
H2 and CH4, and increase the percentage of N2 to the same
extent.
Any unabsorbed CO2 after the explosion will decrease the
percentage of CH4 and increase that of the H2 and N2.
The N2 being determined by difference will necessarily show
the net effect of any and all errors in either readings of the
burette, or in the performance of the analysis.
Specific Gravity of Gas.
Schilling's apparatus for ascertaining the specific gravity, or
density, of gases, is both simple and convenient.
It consists of a glass jar with a metal top into which fits a
brass column having suspended from its base a long graduated
glass tube and at its top a cock and a ground joint socket, into
which sets a socket holding a small glass tip closed in at the
top with a very thin piece of platinum. In this platinum is a
very small hole to permit the passage of gas or air at a very
slow rate. All metal parts are nickeled.
The mode of operation is as follows : The glass jar is filled
with water to or a little above the top graduation of the tube.
The tube is then withdrawn so as to fill it with air. The
cock on the standard is then closed and the tube replaced in
112
the jar. The cock is then opened and with a stop watch the
time is taken that elapses while the water passes from the
lowest graduation to the top or the next to the top graduation.
FIG. 24.
The tube is then withdrawn and filled with gas and the
procedure repeated the same as with air.
The specific gravity, air being one, is obtained by dividing
the gas time squared by the air time squared.
Heating Value of Gas.
(From Report of American Gas Institute.)
Set up the apparatus as shown in cuts of the different sets.
Screw on the inlet water pipe and see that the air vent tube
is in its place in this pipe.
FIG. 25.
Level the calorimeter by means of the screw feet and plumb-
bob.
Connect the center hose nipple on the inlet weir with rubber
tubing to the water supply and the side connection to the sink
to carry away the overflow.
Connect the tubing for water running to weighing pail to the
vertical nipple on the three-way cock on the outlet weir and
for the wasteyto the side nipple.
FIG. 26.
Handle the thermometers with the greatest of care.
Screw the 32° to 100° thermometer on the inlet water pipe
and the 60° to 110° thermometer on the top of the instrument
for the outlet water. Screw the small thermometer in place
on the exhaust flue.
Place the two telescopic sights in position on the water
thermometers, being very careful not to break them off by
pressure against the sights.
Connect the meter to the governor and the governor to the
H5
burner with short pieces of rubber tubing, or with flexible
metal tubing having coupled ends.
The calorimeter should be set up in a quiet, light and well
ventilated room or cabinet, which is free from draughts and
in which the temperature can be maintained constantly at not
less than 6o°F. The room should be provided with a sink and
with a good supply of running water. It is advisable to have a
large shallow overhead covered tank, from which the water
supply can be taken. Should the tank capacity be small and
not hold enough water for a prolonged series of readings, a
small gas water heater may be employed as already noted to
bring the water to approximately the room temperature. It
is desirable to use water that is clear and free from sus-
pended matter in the calorimeter, therefore, a filter should be
installed in the water supply line before it enters the overhead
tank.
If only a single test is desired, gas may be taken from the
house piping, but if an average value is required, a small gas
holder, or averaging tank, should be used, and the gas flowing
into the holder adjusted to a rate of flow to just fill it in the
time during which the sample is to be taken. Care should be
taken to have a short service to this holder in order that an
average sample of gas may be obtained, and if the sample be
taken from a line on which there is no considerable consump-
tion, see that this line is thoroughly purged before sampling.
It is recommended that the gas be metered at a pressure not
to exceed two inches of water; if this is not obtainable, it is
advisable to insert a holder or diaphragm governor in the
supply line to reduce the pressure to within this limit.
Set up the calorimeter so that the overflow and outlet water
can be easily led to the sink. Make water connections with
rubber tubing, being careful not to cramp the tubing. To
avoid air currents caused by the movement of the observer's
body, set up the calorimeter so that the water supply and waste
may be easily adjusted and that all temperatures may be readily
observed. Lead the outlet water to a waste funnel supported
a little above the top of the copper or glass container used in
n6
collecting the water, so that the water can be shifted from the
funnel to the container and back without spilling.
Set up the gas meter facing the observer and level it care-
fully. Then adjust the water-level of the meter, both inlet and
outlet being open to the air. To do this, remove the plug from
the dry well, open the funnel cock and disconnect the tubing on
the outlet of the meter. Add or remove water (through the
funnel or by the cock under the gauge glass) until the lowest
edge of the meniscus just touches the scratch on the gauge
glass, or is even with the fixed pointer. If the meter has been
filled with fresh water the gas must be allowed to burn at
least two hours before making a test. When the water in the
meter is saturated with gas, 20 minutes should be sufficient.
Fill pressure regulator with water, about ^ full, then con-
nect it to the calorimeter burner. Metallic tubing is prefer-
able, but when rubber tubing is used to connect meter, pressure
regulator and burner, connections should be as short as pos-
sible, and should be saturated with the gas.
Turn on gas and allow it to burn for 5 to 10 minutes with
the burner on the table. Shut off gas at burner and watch
hand on meter for leakage. Be sure that all leaks are stopped
before attempting to make a test. Start water running through
the calorimeter at a rate of about 3 pounds per minute. Then
regulate the gas to flow at the rate of 4 to 7 feet an hour, as may
be found by experiment to give the highest result with the gas
to be tested, admitting enough air through the burner so that
the flame shows a faint luminous tip, then insert the burner as
far up into the combustion chamber as the bracket permits,
and observe again the condition of the flame to see that it is
all right, using a mirror.
The excess of air passing through the calorimeter is con-
trolled somewhat by the position of the damper in the exhaust
port, and the best results are obtained by having the excess air
as low as possible and still maintaining complete combustion of
the gas. To determine this position of the damper, some ex-
perimentation may be necessary. Operate the calorimeter
until a thermal balance is established on the inlet and outlet
water thermometers. Start with the damper closed, then open
slightly, observing carefully the outlet thermometer. When
this thermometer reads at a maximum — or in other words,
when the greatest rise in temperature is given to the water,
which is presumably passing through the calorimeter uni-
formly— the damper is in approximately the correct position
for the amount of gas being burned, and the excess air neces-
sary for perfect combustion is at a minimum.
Water should be regulated so that there is a difference be-
tween the inlet and outlet temperatures of about 15° F. The
temperature of the inlet water should vary but little when an
overhead tank is used and the water maintained at room tem-
perature. Be sure that both overflows are running.
Before making the test, the barometer, temperature of the
gas at the meter, temperature of room and temperature of
exhaust products should be recorded. It is desirable to have
the temperature of the inlet water and temperature of exhaust
products as nearly as possible at room temperature, in order to
establish more nearly a thermal balance — the difference in these
temperatures should never, exceed 5°.
Next allow the gas to burn in the calorimeter until a ther-
mal balance is established, or until there is the least change
in the inlet and outlet waters.
The test may now be started by shifting the outlet water
from the funnel to the container just as the large hand on the
meter passes the zero point. Readings are then made of inlet
and outlet thermometers, making the readings as rapidly as the
observer is able to record them during the consumption, prefer-
ably of two-tenths of a cubic foot of gas. At least ten readings
should be made of both inlet and outlet water temperatures.
Water is again shifted from the container to the waste funnel
as the hand passes the zero point the second time. Water is
then weighed or measured. The uncorrected heating value
per cubic foot is obtained by multiplying the difference of the
averages of inlet and outlet temperatures, by the number of
pounds of water and by dividing by two-tenths. This quantity
is divided by the correction factor for barometer and tempera-
n8
ture, obtainable from tables, to give the heating value at 30
inches pressure and 60° F. The weight or contents of con-
tainer should be obtained while the inside is wet. This may be
done by rilling it with water, emptying and shaking for about
five seconds in an inverted position. This will do away with
any correction where several consecutive tests are required
with same container.
A second, and perhaps a third test is advisable, and these
should be made without disturbing the existing conditions,
provided all readings are within the above prescribed limits.
In practice the operator should get consecutive results on the
same holder of gas within ten (10) B. t. u/s. Under such
conditions an average of the results may safely be taken.
RESULTS AS OBTAINED BY CALCULATION.
The method of calculating the calorific value of the gas
from the observations indicated is very simple when all read-
ings are made in English units, as recommended, and entered
in some form conveniently arranged. A simple record sheet
is shown herewith, a convenient size for which is 5 by 8 inches.
The averages of the inlet and outlet water temperatures are
determined and necessary corrections for thermometer errors
are made. The difference in these averages should give the
rise in temperature of the water. This rise in temperature of
the water is therf multiplied by the number of pounds of water
passed through the calorimeter during the test.
The product of these two is then divided by the quantity
of gas burned — 0.2 of a cubic foot. This quotient will give the
heating value of one cubic foot of gas in B. t. u.'s at the in-
dicated temperature and barometric pressure. To correct this
to 60° F. and 30 inches pressure, divide by the "Correction
Factor" for the indicated temperature, and pressure as ob-
tained from some standard table. [Printed on card sent with
apparatus.] The final result will be the corrected heating
value of the gas tested, in B. t. u.'s.
H9
Expressing the above in a formula we have :
W X T
B. t. u.'s per cubic foot = — — .
W = weight, in pounds, of water passed.
T = the average difference in temperature, in degrees
Fahrenheit, between inlet and outlet water.
G = corrected volume of gas burned, in cubic feet.
The correction for atmospheric humidity is made, finally, if
so desired.
USE OF COMPUTER.
The labor of making the calculations for determining the
heating value from observations of a calorimeter may be
lessened by the use of a heating value computer. The computer
consists of a circular slide rule, with divisions corresponding to
the readings made on the calorimeter. This computer gives
the corrected heating value of a cubic foot of gas in B. t. u.'s,
having the barometric pressure and temperature of the metered
gas, and the difference in temperature between the inlet and
outlet water, and the pounds of water passed. This computer
is designed to operate within the limits of from 300 to 800
B. t. u.'s. Should a gas of a lower or higher heating value be
measured, the computer can still be used by dividing or multi-
plying one or the other of the factors in its computation. A
cut of this computer can be found on page 373, Vol. Ill, Pro-
ceedings of the American Gas Institute.
Corrections for Atmospheric Humidity.
(From Report of American Gas Institute.')
This correction is found to be the greatest when the per-
centage of humidity of the atmosphere is the lowest. The
reason being that the relatively dry air entering the calorimeter
causes to be carried out in the exhaust products a larger
amount of the water in the form of a gas or vapor, that is
formed by the combustion of the gas, and which does not
condense, and, therefore does not give up its latent heat to the
calorimeter.
I2O
The humidity correction should correct for any discrepancy
in water vapor carried in by the air and gas, compared with
that carried out by the products of combustion.
Owing to the contraction in volume, during the combustion
of ordinary illuminating gas and air, this discrepancy is prac-
tically nothing when the percentage of atmospheric humidity is
about 80 per cent., at normal temperatures, and the excess of
air introduced for combustion is about 30 per cent.
In correcting for atmospheric humidity it is assumed that
the gas is saturated with water vapors — having passed through
a wet meter. This assumption might not be absolutely true,
but the percentage of saturation has been found always to be
high, and as the volume of gas is only about one-eighth of the
mixture, the error involved may be neglected.
TABLE I.— CORRECTIONS TO OBSERVED HEAT TO GET TOTAI, HEAT
VAUTE. AIR, GAS AND EXHAUST MUST BE AT
THE SAME TEMPERATURE.
If 7 volumes of air per volume of gas are used.
Humidity Room temperatures
Per cent. 65° 70° 75° 80° 85° 90°
10 +4.8 +5.7 +6.7 +7.9 +9.2 +10.5
20 +4.1 +4.9 +5.7 +6.8 4-7.8 4- 9.0
30 4-3.4 4-4.1 +4.7 4-5.6 4-6.5 4- 74
40 4-2.7 4-3.2 4-3.7 +4.5 4-5.2 4- 5.9
50 4-2.0 4-2.4 4-2.8 +3.4 4-3.8 4- 4.3
60 4-1.3 4-1.6 +1.8 +2.2 +2.5 + 2.8
70 +0.6 +0.8 +0.8 +1.0 -+I.2 +1.2
80 —o.i +0.0 —o.i —o.i —o.i - 0.3
oo —0.8 —0.9 —i.i —1.3 —1.5 — 1.9
100 — 1.6 — 1.8 — 2.0 —2.4 — 2.8 — 3.4
Note — These corrections are expressed in B. t. u.
Directions for Using Or sat Apparatus.
The gas burette A (in Fig. 27) is attached to the levelling
flask B, which is filled with water. By raising B, A is filled
with water to the uppermost mark. In order thus to fill A
with water, the air must have opportunity to escape from the
uppermost portion of A.
The absorption pipette D is used to absorb carbonic acid gas.
121
It contains such a quantity of caustic potash solution that when
the solution is drawn entirely into the front part of the pipette
(the proper position for the solution when the pipette is ready
for use), the front part of the pipette is filled with the solution,
FIG. 27.
and the rear part is empty. The solution is drawn up into the
front part of the pipette D, as follows : Communication is es-
tablished with the outside air by means of the stop-cock a.
Stop-cock d, e and / are closed. A is filled with water by rais-
122
ing B. Stop-cock a is closed, stop-cock d is opened, and the
solution in pipette D is drawn into the front part of the pipette,
by lowering B. When the solution has filled the front part of
D, close stop-cock d.
Rubber bags are usually attached to the capillary opening at
the rear of the pipettes to prevent free access of air and to
allow the escape of the confined air when the solution is per-
mitted to flow back again in the pipette after having been used.
Pipette B is for the absorption of oxygen gas, and pipette F
for the absorption of carbon monoxide gas. Pipette B is filled
similar to D, with a solution of pyrogallic acid or with thin
sticks of phosphorus in water. In case the phosphorus is used,
the pipette is covered with black paper to prevent the action
of light on the phosphorus. Just as in the case of D, before
using H and F, the solutions are drawn into the front parts of
the respective pipettes, and held there by closing their respec-
tive cocks. Pipette F contains a solution of cuprous chloride.
The front part of each of the pipettes contains a bundle of
glass tubes, in order to increase the absorption power of the
pipettes. The glass tubes for pipette F contain curved copper
wires to maintain the cuprous chloride solution at a constant
strength.
The pipettes being in readiness with stop-cocks d, e and /
closed, and A open, burette (A) is filled with water by raising
(B). The other end of the capillary tube or beam is now con-
nected with the gas to be tested. A bent tube is provided for
purifying the gas before allowing it to pass into the apparatus.
This tube is fastened outside the case on the upper left side,
and is connected with the capillary stop-cock tube by means of
rubber tubing. Before attaching the bent tube it is filled with
a sufficient quantity of calcium chloride, or glass wool. When
everything is ready, with a connection made for the gas to
enter the apparatus through the bent tube, (B) is lowered, by
which means the gas is drawn into A to the O mark. Par-
ticular care must be taken that there is exactly 100 cubic cen-
timeters of the gas. Stop-cock A is now closed, stop-cock D
opened, vessel (B) raised, burette (A) filled with water, and
123
the 100 cubic centimeters of gas forced into the pipette D.
Here it is allowed to stay for some minutes, the pipette being
shaken slightly, if practicable, in order to bring the gas fully
into contact with the solution.
When the absorption is complete, the flask (B) is again
lowered, thus drawing the gas back again into A. One hun-
dred cubic centimeters minus the amount of gas remaining
shows the amount of carbonic acid gas absorbed by the caustic
.potash solution. Stop-cock d is now closed, stop-cock e opened,
and (B) again raised thus forcing the gas into H. Here the
gas is treated as it was in D, (B) is then lowered, the gas
forced back into (A) and the amount read. The gas unab-
sorbed by the caustic potash minus the present remainder
shows the amount of oxygen which has been absorbed by the
pyrogallic acid, or by the phosphorus, as the case may be.
Stop-cock e is now closed, stop-cock / opened, and (B) again
raised. The gas is now forced into F. Here especial care
must be taken to be sure that complete absorption takes place.
When the absorption is finished, (B) is again lowered and the
gas drawn back into (A). The previous remainder minus the
present remainder shows the amount of carbon monoxide
which has been absorbed by the cuprous chloride solution.
The last remainder is usually reckoned as nitrogen, though it
contains also small quantities of other gases. In case there is
reason to suspect the presence of considerable quantities of
hydrogen, a four-pipette apparatus, Fig. 28, is used.
The gas left over from the last operation is increased by the
admission of air from the outside until it is again as nearly
as possible 100 cubic centimeters. The air added will allow
of the burning of a quantity of hydrogen corresponding to
two-fifths of its volume; that is, twice the volume of the oxy-
gen contained in the air. This suffices for ordinary producers'
gas; but when analyzing "Water Gas" or similar mixtures
containing a rather considerable quantity of hydrogen, a
smaller quantity of gas must be employed for analysis, or also
oxygen is used instead of air. After reading off the total
volume, the spirit lamp (h) is lighted and turned so that it
124
heats the capillary (i) very gently. Then (B) is raised, g be-
ing open and all other stop-cocks closed.
FIG. 28.
The gas passes through the capillary i, into the pipette G,
and then on lowering (B) the gas passes back again into the
burette (A). One end of the palladium asbestos should be-
come hot in this operation. The volume of gas is read off
and the passage through i is repeated. If, which is usually not
the case, a further contraction is now observed, the passage
through I must be repeated once more. The residual gas is
now finally measured, and two-thirds of the diminution is
read as hydrogen, the other one-third being, of course, oxygen.
125
REAGENT.
SOLUTIONS FOR ABSORPTION PIPETTES.
(Method in use December 7, 1914.)
Potassium Hydrate. — Five hundred grams of potassium hy-
drate (not purified by alcohol) are dissolved in 1,000 cubic
centimeters of water. Capacity: I cubic centimeter absorbs
40 cubic centimeters of CO2. Sodium hydrate, at present, has
replaced KOH, in many works. This reagent, although not
quite as active, may be used ; but solutions should be changed
oftener to avoid clogging of capularies by sodium bicarbonate
formed.
Potassium Pyrogallate. — Fifty grams of pyrogallic acid are
dissolved in 1,000 cubic centimeters of the solution as made
above.
Cuprous Chloride. — Mix 35 grams cuprous chloride (CuCl)
and 200 cubic centimeters HC1 (specific gravity 1.19) and to
this arrange a bunch of copper wire to reach the entire length
of the bottle.
LIFE OF REAGENTS.
If the solutions are protected from the air, their life is about
as follows : One cubic centimeter of caustic potash solution
will absorb 40 cubic centimeters or more of CO2. The absorp-
tion of O by pyrogallic solution should be at temperatures
not less than 15° C. ; I cubic centimeter of pyrogallol solution
will absorb about 13 cubic centimeters of O. Phosphorus will
last a long time, inasmuch as the oxidation products are dis-
solved off by the water leaving the phosphorus free to com-
bine with more O. One cubic centimeter of the cuprous
chloride solution is equal to about 16 cubic centimeters of CO.
The palladium renews itself constantly by contact with the air,,
so that its activity is almost inexhaustible.
There is also largely used, the modification of the Orsat ap-
paratus known as Franklyn Flue Gas Analyzer for the deter-
9
126
mination of CO2, O and CO, which is explained by the follow-
ing illustrations. Its chief advantages are, its compactness,
FIG. 29.
that is, its parts are more compact and not as easily broken as
those of the Orsat Muencke apparatus.
CONSTRUCTION AND OPERATION OF HYGROMETER FOR DETER-
MINING THE MINIMUM TEMPERATURE OF SATURA-
TION OF GAS IN DISTRIBUTION MAINS.
The instrument is employed to determine the minimum tem-
perature to which illuminating gas has been cooled on its
way to the burner, its action being dependent upon the fact
127
that the gas will be saturated with vapor at the minimum tem-
perature to which it has been cooled. The instrument reduces
a small quantity of the gas back to the minimum temperature,
and upon further slightly cooling, it gives evidence, in the
deposition of dew, that the point has been reached. The tem-
perature is then noted on a delicate thermometer placed inside
the instrument.
The function of the instrument is therefore to duplicate, on
a small scale, what has previously taken place in the main.
Construction of the Apparatus.
The apparatus consists of an interior glass vessel A (Fig.
30) known as the condensing tube, the glass jacket D sur-
rounding the condensing tube, the thermometer support O,
and the thermometer T which is suspended in the condensing
tube. The cap K covers the top of the instrument and carries
the burner-head E. The whole is mounted on a base provided
with a cock, which is so constructed that the gas may be made
to pass straightway into the instrument or first through either
one of the scrubbers ( G — //). The needle valve Z, is pro-
vided in order to permit of the gas being passed directly to
the burner instead of through the vaporizing tube. The in-
strument may be taken apart at C for the purpose of cleaning
the jacket; the cap also unscrews, giving access to the con-
densing tube. The two scrubbers may be unscrewed at the
bottom for filling and cleaning.
Setting up the Apparatus.
The support for the apparatus M is screwed on to a con-
venient gas bracket (no rubber connections should be used),
the outside jacket D is screwed on the base of the apparatus at
N, and the instrument then placed upright on the support with
the handle of the cock toward the observer. The cap K is re-
moved and the thermometer support C pulled out and the
thermometer placed in position, as shown. The cap K is then
replaced and surmounted by burner-head £. The right-hand
scrubber cover H should then be unscrewed from the base,
128
FIG. 30.— Hygrometer.
129
uncovering the calcium chloride scrubber. This tube should
be filled with small pieces of calcium chloride. Replace the
scrubber cover, screwing firmly into place with the fingers.
Likewise unscrew the left-hand scrubber cover C and see that
the glass tube is filled with rubber bands; then replace cover.
The gas should now be turned on and lighted, the cock at
the base of the instrument being turned so that the gas passes
straight into the jacket. By turning the cock to the right or
the left, the gas can be made to pass through the scrubbers
(G — H) at will, or cut off entirely. A good flow of gas
(from 2 to 3 feet per hour) should be obtained either straight-
way or through the scrubbers. The instrument is now ready
for observation.
Making the Test.
Shut off the gas at the cock on the base of the instrument
and lift off the burner-head. Place the stem of the small
funnel sent with the instrument through the cap and pour
pentane or ether into the condensing tube until it contains
about i inch of the liquid. Replace the burner-head and open
needle valve L. The gas is now turned on with the cock set so
that it passes straight into the jacket and out through the
burner-head, the condensing tube being by-passed. By
throttling the needle- valve L, a portion or all of the gas may
be made to bubble through the pentane, the rate of its pas-
sage through the pentane being regulated entirely by the
needle-valve. The vaporization of the pentane causes a re-
duction in temperature of the tube and finally dew will be de-
posited on its outer surface.
The temperature at which the dew commences to deposit
opposite the bulb of the thermometer is noted and recorded as
the "dew point" or minimum temperature of the gas. When
this point is reached the needle-valve should be opened, by-
passing the condenser tube. Soon the thermometer will rise
and the dew will disappear. The observance of the point of
disappearance furnishes a check upon the first reading. The
gas before passing into the instrument may be first passed
130
through the scrubbers (G — H) to remove a portion of the
unfixed hydrocarbon vapors or water vapor. The functions
of these scrubbers are described in a paper by C. C. Tutwiler,
published in the Journal of the American Chemical Society,
April, 1908, and republished in the American Gas Light Jour-
nal, of April 20, 1908.
TAR.
For tar shipments it is, as a rule, sufficient to determine the
specific gravity and the water in the tar. The following two
methods are recommended for these determinations. For a
more complete analysis, refer to chapter on Tar Products.
SAMPLING.
Tar is best sampled while being unloaded from or loaded in
the tank car or barge. A pet cock with a nipple projecting
about one-third of the diameter, should be placed in the pipe
line and a continuous stream of tar drawn off into a barrel
during the time of unloading. The pet cock should be so regu-
lated that the sample will represent approximately o.i per
cent, of the shipment. The tar may then be stirred up and a
sample taken from the barrel. Samples of tar should be placed
in heavy clear bottles or screw top tin cans. When necessary
to sample from storage tanks, or wells, it should be done by
means of a "thief." This is particularly necessary when differ-
ent shipments of tar of widely different gravities have been run
into the same tank. A simple and efficient apparatus may be
made from a piece of 2-inch pipe provided with a lever handle
cock. This may be closed by means of a small iron rod as
shown in Fig. 31.
By cutting away part of the cock and one-half of the plug,
an opening nearly as large as the interior of the pipe is pro-
duced. In taking the sample, the cock is opened and the
"thief" slowly lowered to the bottom of the tank, well, or car,
the "thief" having previously been rinsed with the liquid to
be sampled, the cock is closed, the "thief" is withdrawn, and
the sample run into a bottle. This operation is repeated until
a sample of about I gallon is obtained, after which the con-
tents should be thoroughly mixed, and a portion taken to serve
as a smaller sample for analysis.
It should be noted that this method cannot be used with
horizontal cylindrical tanks.
u
FIG. 31. -Thief sampling tube.
In the case of tar where there is always a certain amount
of water or ammoniacal liquor floating on the surface, it seems
best to attempt to locate the level of the water or liquor,
taking a sample at this point, and then sample a lower portion
of the tar which is reasonably free from water, and by calcula-
tion, estimate the total quantity of water present.
DETERMINATION OF SPECIFIC GRAVITY.
When there is no free water the gravity may be determined
with a hydrometer after bringing the sample to normal tem-
perature or by observing the temperature and correcting as
follows :
Specific gravity at 70° C. = specific gravity observed at
jo c. + (T— t) X 0.0008.
It is recommended that the specific gravity be taken at 25°
C. Where more accurate results are required the pycnometer
bottle is recommended. These are straight sided thin glass
bottles with a ground stopper the full size of the bottle and
provided with a capillary hole in the center of the stopper.
The bottle is dried and weighed empty and filled with water
at normal temperature. It is nearly filled with tar and weighed
again, it is then completely filled with water, and brought to
132
the normal temperature, the excess water removed and the
bottle dried and weighed.
Specific eravity - (Wt. bottle X tar) - (Wt. bottle)
~ Wt. water full — Wt. water added"
DETERMINATION OF WATER.
The sample should be very thoroughly agitated to insure
that the portion taken for analysis is representative.
FIG. 32.
133
The apparatus is set up as shown in Fig. 31.
Put 25 or 30 cubic centimeters of benzol in a 250 cubic
centimeter cylinder, add 200 cubic centimeters of the well
mixed sample, pour into the copper still and wash out three
times with benzol using 25 to 30 cubic centimeters adding
washings to still.
Fasten on Ud with the clamp using a gasket of manila "de-
tail" paper, connect apparatus as shown in Fig. 27. Start
ring burner at top of still and lower after the water has been
driven off until the thermometer reaches 200° C.
The distillate is collected in two 100 cubic centimeter grad-
uated cylinders.
Where an excessive amount of water is suspected the dis-
tilling head is replaced with the expansion chamber shown in
Fig. 32, the side outlet and receiver is connected with a filter
pump and the distillation carried out in a partial vacuum.
The contents of the receiver is then transferred to a measuring
cylinder.
AMMONIA.
Ammoniacal Liqiior.
SAMPLING.
When the liquor is contained in a tank with straight sides,
sampling is done with a "thief," which may be a bottle thief
or a pipe thief, A very satisfactory bottle thief for ammonia-
cal liquor may be made as follows from a one-quart milk
bottle.
Enough shot are put into the bottle to overcome its buoy-
ancy and cause it to sink easily when immersed in water. The
shot are held in place by pouring over them a thin paste of
Plaster of Paris. The bottle is provided with a two-hole cork
or rubber stopper through which pass two glass tubes pro-
jecting about one inch above the stopper. One tube extends
just below the stopper; the other to about % inch above the
bottom. In use the thief is lowered at even speed through
134
the liquor to be sampled till it strikes bottom, and then immedi-
ately raised at even speed. The speed must be such that the
bottle is not completely filled when it is drawn out from the
liquor. The thief is emptied, and the operation repeated till a
sufficient quantity for the sample is obtained. It will be noticed
that the thief does not take a portion from the liquor lying be-
low about 8 inches from the bottom. When there seems reason
for thinking that this bottom layer may be considerably differ-
ent from the rest, the pipe thief should be used.
The pipe thief consists of an iron pipe of 1^4 inches to 2
inches size, as desired, long enough to reach to the bottom
of the tank. Its lower end is provided with a plug-cock hav-
ing a lever handle which points across the pipe when the cock
is open. A rod or chain is attached to the end of the handle.
The thief is slowly lowered, with the cock open to the bottom
of the tank. The cock is then closed by pulling on the rod
or chain, and the thief withdrawn and emptied. The operation
is repeated till a sufficient sample is collected.
When liquor can be sampled during pumping, this should
be done in preference to taking a sample from the tank. This
is especially true with tank cars or other horizontal cylindri-
cal tanks. A pet cock should be attached to the pipe line on
the outlet of the pump by a nipple projecting into the line
about one-third of the diameter of the latter. A small stream
of liquor should be drawn at steady speed from the pet cock
through a tube into a covered receiver of not much larger
size than the sample desired. Where the question of sale is
involved, an amount equal to o.i per cent, of the total quan-
tity should be collected in the receiver. After shaking, a
sample is taken from the latter for the laboratory.
In collecting a running sample, as described above, it is
necessary that the rate of flow and the pressure in the line
where the pet cock is inserted be uniform throughout the un-
loading of the tank. When a tank is unloaded by gravity,
these conditions are not fulfilled and therefore a pet cock in
the line does not give the true average sample. In such a
case, however, an approximately correct sample can be ob-
135
tained if several running samples are taken, each represen-
tative of a definite fraction of the whole quantity, such as one-
sixth or one-eighth. Equal portions are taken from each sep-
arate sample, and mixed to form the composite sample.
In sampling from a horizontal cylindrical tank, the thief
cannot be used, because equal depths of liquor at different
elevations represent quite different volumes. A good approxi-
mation to a true average, however, can be made by taking
several samples at varying depths, which latter are chosen to
represent a division of the tank into equal parts by volume.
Equal amounts are taken from the various samples, and mixed.
The greater number of the samples, the more representative
is the mixture. The following table shows the depths, ex-
pressed in per cent, of the diameter at which samples should
be taken, when six, eight, ten and twelve samples are desired :
For 6 samples For 8 samples For 10 samples For 12 sample
Percentage 13.7 11.3 9.8 8.6
30.0 24.4 20.7 18.3
of 43-6 35-3 3°-o 26.2
56.4 45-2 38.3 33-3
diameter 70.0 54.8 46.1 40.1
86.3 64.7 53.9 46.7
75-6 61.7 53.3
88.7 70.0 59-9
79.3 66.7
90.2 73-8
81.7
91.4
These depths represent the centers of gravity of zones of
equal volume.
For collecting these samples, the bottle thief is suitable.
The ends of a short piece of rubber tubing with a string tied
around its middle are pushed lightly over the tubes of the
thief, thus sealing them. The bottle is then lowered gently
to avoid disturbance of the strata, till the tops of the tubes
are at the right depth for taking the first or top sample. The
rubber tube is then drawn off and the thief allowed to fill.
The second sample from the top is then taken, etc.
i36
The foregoing table is intended for use on completely filled
tanks. It may, however, be used for sampling partially filled
tanks, without much error, if several samples are taken, and
special calculation is made as follows for the top sample : The
boundary between zones is assumed for this purpose to be
half-way between the centers of adjoining zones. The top
zone will then consist of the liquor from the surface to the
first zone boundary below, and the top sample should be taken
half-way between these points. The amount of this top zone
sample taken for the mixed sample, should be in the ratio of
the actual depth of the top zone to its full depth according
to the table.
Tanks and tank cars of ammoniacal liquor, often contain
tar, which may either float or sink depending on its nature.
To estimate the depth of the floating tar, use a glass tube of
*/% inch or more diameter whose lower end is fitted with a
rubber stopper, which may be drawn up into the tube by a
string fastened into the stopper and passed up through the
tube. Lower the tube slowly through the tar layer, with the
stopper suspended well below the tube end. When the tube
end is well into the liquor, draw up the stopper, closing the
tube. Measure the depth of the tar layer.
To measure the depth of tar in the bottom of the tank,
attach a piece of cotton wicking to a rod. Wet the wicking
with benzol or other light colored tar solvent, and put the rod
into the tank. The tar will color the moist wicking.
SPECIFIC GRAVITY.
The determination of specific gravity is made by hydrom-
eter. A regular specific gravity hydrometer, graduated to read
to the third decimal place is used. However, in cases of doubt
or dispute, a pycnometer (Sprengel tube) should be used.
The standard temperature for taking the gravity is 60°
F. The gravity is referred to water at 60° F. A hydrometer
jar of the liquor to be tested should be brought to that tem-
perature by immersion in water, and the reading taken.
137
When it is desired to know accurately the weight of liquor
present in a tank or tank car, the gravity must naturally be
taken at the temperature at which the volume of the liquor is
also measured. This may be done by taking the gravity of a
freshly drawn sample at the tank; or the temperature may be
noted and the regular sample brought to that temperature in
the laboratory for a determination of the gravity.
The Committee recommends the general use of the specific
gravity scale in reporting the gravity of ammoniacal liquor.
It recognized, however, that the use of the Twaddle hydrom-
eter is common in several of the older companies. Readings
in the Twaddle scale may be changed into readings on the
specific gravity scale by the use of the following formula :
Specific gravity = i.o divided by 0.005 Tw.
The objection to the use of the Twaddle scale, is that it is
often assumed that the value of the liquor in terms of "ounce
strength" may be found by multiplying the Twaddle reading
by two. There is, however, no general numerical connection
between the hydrometer reading of a liquor and its content of
ammonia.
(In any one plant, operating regularly under the same con-
ditions and using the same coal, it is true that an increase in
the strength of the liquor will generally be accompanied by an
increase in its gravity, and in such case the hydrometer read-
ing offers a simple means of following the daily operation of
condensers, scrubbers, etc.)
Since considerable changes in the reading occur when the
temperature is much different from 60°, and since it is incon-
venient to adjust the temperature of the liquor in works test-
ing, the following table has been prepared to find the equiv-
alent reading at 60° from a reading taken at a different tem-
perature. The numbers are degrees on the Twaddle hydrom-
eter. The table is not perfectly correct for all ammoniacal
liquors but is sufficiently so for the routine testing for which
it is intended.
138
w
rt
88888888§
0
S^ffS,^^!?^
BU
p
j^
oo r^\o 10 T co PI M
r^vo 10 -<t co w M i
s», a
<!
-
£
PI
OS
oo Tt~w r-*co^ioo 10
0 M (N (N COcOrMOrr
1 K S,
w
oo' t^-vd 10 TT co pi M
t^.vO IO ^" f*> 04 IH I
!||
-
w
00
g^s-crs^s5??
00
J?^^C0^5^-K^
fl fi "S
H ^§
H
OO l^^O IO •<*• CO PI M
• a ft
W
,4
g
p
55
smm^
"
OO COO lO^vO M IO^\
M w rCcO^Ti-ioiOcO
t^.\O IO ^f CO W M I*
I!}
<!
as
OO vO ^ CO W M ONt^lO
cooo^OMOO^oor.
n fe *
~ 1 8"
H
s
10
oo" r^-so 10 -<i- co oi M
^
t^-^O* IO 4 CO Pi i-I |'
a » 10
0-0
(4
p<
IO
O* O OO VO iOrO>-< 5s *"""
10
OOCOOOCO^CO^M^
?- ?
g
06 l"**vC IO ^ ro CS M
t^^O iO ^ to W t-< |
*li
Q
g
•<*•
t^COPIOSOOvOCOM^
^;
cooo Pir. covo O^M
- § <1
§1 d
CM
oo r^\o 10 ^" co PI *H
t^<O IO Tf CO PI IH 1
:Ji
O
a
K
COPIPIPIPIW'HWM
rs
oo co r^ M vo o TI- t^oo
CO •»)- •<*• 10 IO>O >O >O PI
^|8
« S o
,4
oo r>«vo 10 4 co pi M
t^-vO IO T CO PI w 1
g « t>
W ^3 <U
t4
«<
u
PI
10 w avvo co o r^ 10 «-
COCOPIPIPIPII-II-II-I
PI
cO^jOg^O.0
|||
«!
OO^^^COPIM
r>>vo 10 ^ co w M j
fcl ^
fc
O
i
M
33R<ras>g«eg>
M
.oPi^as^oco^
* 8«
in
00 t^VO IO TT CO PI IH
t^vO >O •* CO PI w
S . B
(U J3 <H
to
o
&
^S'ftaffsa&J
o.
B'ftStftfR.SrRS
* - £ .
*-• O «-; o
o ^ S ^
><
OO^VO^^-COWM
C-vO^^tOPl'- ' |'
_. <u a> J-
s ^ *- ^s
S
^
0
t^
$
J.O^MCO^^
!"§ s^
1,8 S3
A
oo i^\o 10 ^ to PI IH
t^.vO IO ^ CO PI IH 1
0 •" <U T3
CSS g
a
g
*
oo' ri-o 10 4 co PI «
8
r^vo' in •* to « IH i"
3 tn (fi ^
2^ ?1
X -° ^ Si
§
fc
C/2
5?
oo' t^-^o' 10 TJ- CO PI i-i
£
l^ ON PI ^-00 ON PI •*• T}-
t^.\O IO 4 CO pi M I*
|
P 1 Q- i
^§{58
FH
§
*
oo' r^-o' 10 T}- co N w
$
PI CO\O CX) M PI IO\O P»
t-. i-. r>- t^-oo oo oo oo w
r^-vo* 10 4 co PI M
!-" ts "S j
5 5 2 -
.sS 4«
(A
10
\O lOlO-'TTj-COPI P?C"
%
t^oo o PI ^" 10 r^oo o
r^ t^oo oo oo oo oo oo M
1 §-s ^
e be cs -o
O
oo i^^o 10 •* co PI »H
t^vO IO Tj- CO PI IH 1
•§| S j;
M
5
00 t^-vd IO •* CO PI IH
3
r^vo" 10 -<i- co pi w
lisa
Zl *~ v <u
£ h 1 i
M
o
o
5
M Tj-oO COOO O cOsO 00^
r>.vq 10 10 TI- •* co PI IH
oo' r^-^d 10 4 to p5 w
CO
(^•-0' 10 -4 co PI M ' i'
Jfli
^2 a >, cs
CS O rC
w
M
£3
JH
a
^i-OO M vo O co *O t^ ^\
r^\o ^o 10 10 ^ co PI M
oo r>-AC 10 4 co PI IH
PI
r^^o* 10 4 co PI H! ' i*
Sfc*i
5 fl ^ 3
•<
j*
„
00 w 10 ON PI IO r^OO O\
t~* t^VO IO IO ^- CO PI IH
_,
vONOvO-O^Og-^PI
2 * ft w
3 1; a °0
W
PL,
oo r^vo 10 'i- co N IH
r^^o 10 ^ co w »-» i
H S I*
0
oo {CS^S ^^%r?8
888888888
II
H
00 t^^O IO ^" CO C1) M
-;
00 t>-vO IO "^ CO CS M I
££.2
139
Ammoniacal Liquor.
DETERMINATION OF TOTAL AMMONIA.
APPARATUS REQUIRED.
A 500 cubic centimeter round-bottomed long-necked flask (a
Kjeldahl flask) into whose neck is set by a rubber stopper a
bulb tube with the bulb portion bent to 45° off the vertical, or
some other form of Kjeldahl connecting bulb, to prevent the
mechanical carrying of spray into the condenser.
Inside an ordinary glass Liebig condenser jacket is slipped
a block tin tube about ^ inch outside diameter, in place of the
usual glass condenser tube. The tin tube can be obtained
from a plumbing house. There is, however, no objection to
the use of a glass condenser as shown in Fig. 28 if preferred
by the chemist. About 7 inches of tin tube projects beyond
the jacket and this portion is bent back on itself to an angle
of 135° from the vertical and joined by rubber tubing to the
connecting bulb previously mentioned.
To the lower end of the tin condenser tube is attached a
plain bulb tube of about 150 cubic centimeters capacity. The
lower end of this will dip into the beaker of, standard acid.
The object of the bulb is to prevent the accidental sucking back
of the contents of the beaker. The equipment of flask and
condenser should be carried on a single stand.
There will also be needed one 25 cubic centimeter pipette
for sampling weak liquors ; and one 100 cubic centimeter pip-
ette and one 1,000 cubic centimeter graduated flask for use
with concentrated liquors. On account of the inaccuracy of
some of the volumetric apparatus on sale, the pipettes should
be checked by filling them with boiled distilled water at room
temperature, discharging into tared small stoppered bottles
and weighing the water. The weight should not vary by more
than 2 parts in 1,000 from the weight given in the tables (See
circular No. 19 of the Bureau of Standards for complete
tables). The water from a 25 cubic centimeter pipette cali-
brated for 20° C., should weigh 24.948 grams at 15° C. ; 24.929
grams at 20° C.; 24.904 grams at 25° C. Water discharged
140
FIG. 33.
from a 100 cubic centimeter pipette, calibrated for 20° C.
should weigh 99.793 grams at 15° C. ; 99718 grams at 20° C.;
99.617 grams at 25° C. New marks should be made on the
pipettes if they are in error by more than the allowed amount.
It should be determined also that the 1,000 cubic centimeter
flask holds ten fillings from the 100 cubic centimeter pipette.
Operation A. — For liquor under 3 per cent, ammonia (ordi-
nary weak liquor). Put 150 cubic centimeters distilled water
into the 500 cubic centimeter flask and run in 25 cubic centi-
meters of liquor from the pipette. Add 25 cubic centimeters
of 30 per cent, sodium hydroxide solution (300 grams NaOH
in 700 cubic centimeters water) and a small piece of gran-
ulated zinc to prevent bumping. The addition of a small bit
of parafnne will hinder troublesome foaming.
Put 50 cubic centimeters of normal sulphuric acid and 50
cubic centimeters of water in a 400 cubic centimeter beaker
and support the beaker so that the bulb tube on the condenser
end dips about y2 inch below the surface of the acid. Con-
nect up the apparatus and heat up gently till the air is expelled
and the boiling is steady. All the ammonia will be driven off
with the first 100 cubic centimeters of distillate. From time
to time lower the beaker so that the seal of the bulb tube is not
much over ]/2 inch. When about 100 cubic centimeters has
distilled over, lower the beaker clear of the tube and allow
the distillate to rinse the inside of the latter. Wash the out-
side with a wrash bottle.
Titrate the solution in the beaker with half-normal am-
monium hydroxide or normal sodium hydroxide, using coch-
ineal or methyl orange as indicator.
Calculate the number of cubic centimeters of normal acid
which have been neutralized by the ammonia from the liquor.
The percentage of ammonia is found by multiplying this num-
ber of cubic centimeters by the factor 0.06813 and dividing by
the specific gravity of the liquor. In calculating the percen-
tage strength, the gravity used should properly be that of the
liquor at temperature of pipetting. The difference, however,
10
142
may be disregarded unless the temperature varies from 60°
F. by more than 10° or 12°.
B. For Concentrated Liquors. — One hundred cubic centi-
meters of the concentrated liquor are made up to 1,000 cubic
centimeters and an aliquot of 100 cubic centimeters taken for
the distillation. This is put in the distilling flask with 75 cubic
centimeters of water and 25 cubic centimeters of 30 per cent,
caustic soda solution. Zinc and paraffine are added as before.
The ammonia is received in 100 cubic centimeters of normal
sulphuric acid in a 400 cubic centimeter beaker, or in 125
cubic centimeters for very strong liquor.
Calculate the number of cubic centimeters of normal acid
neutralized by the ammonia. For percentage of ammonia mul-
tiply this number of cubic centimeters by 0.17033 and divide
by the specific gravity of liquor.
C. For Waste Liquors From Ammonia Stills. — Two hun-
dred cubic centimeters of the waste liquors are put in the dis-
tilling flask, with 25 cubic centimeters of 30 per cent, caustic
soda solution together with zinc and paraffine. One hundred
cubic centimeters is distilled off and received in 20 cubic centi-
meters of normal acid diluted with 80 cubic centimeters of
water.
Calculate the number of cubic centimeters of acid neutral-
ized by the ammonia. For percentage of ammonia, multiply
this number of cubic centimeters by 0.00852.
The Committee strongly recommends reporting the amount
of ammonia in liquor as a percentage, as described above.
Several of the older companies, however, are in the habit of
reporting in so-called "ounce-strength." Two different mean-
ings appear to be given to this latter term. It is sometimes
defined to mean the number of ounces of 100 per cent, sul-
phuric acid which will be neutralized on direct titration by
i Imperial gallon (277.27 cubic inches) of this liquor. Only
the free ammonia is taken into account in this test. For the
determination, see the determination of free ammonia by titra-
tion, as described below.
Again "ounce-strength" is defined to mean the number of
143
ounces of 100 per cent, sulphuric acid which will be neutral-
ized by the total ammonia contained in I U. S. gallon (231
cubic inches). If figures in "ounce-strength" of this definition
are sought they may be obtained from the results of the dis-
tillation analysis above described by the following calculation :
A. For Weak Liquors. — Multiply the number of cubic cen-
timeters of acid which have been neutralized by the ammonia
from the liquor, by the factor 0.26196.
B. For Concentrated Liquors. — Multiply the number of
cubic centimeters by the factor 0.6549.
C. For Waste Liquors. — Multiply the number of cubic
centimeters by the factor 0.03275.
It should be noted that the ounce strength as thus found is
really the ounce strength of the liquor at the temperature of
sampling with the pipette. The ounce strength will increase
proportionately as the gravity increases with lower tempera-
tures and vice versa. The difference in value for 10° F. will
amount to about 1.5 parts of 1,000. The liquor, as sampled,
should not therefore vary by more than 10° from 60° F.
In the method described for the determination of ammonia
in ammoniacal liquor, it is usually assumed that ammonia is
the only substance distilling off, which will neutralize the sul-
phuric acid. This is not strictly correct, for the pyridine
present in the liquor will distil and will neutralize some of the
acid, thereby causing the apparent ammonia found to be larger
than the true value. The amount of pyridine is usually small
but where high accuracy is desired, a correction should be
made for it, in the following manner:
In the determination of pyridine, as described below, there
is found the number of cubic centimeters of normal acid
which are neutralized by the pyridine contained in a given
amount of liquor. From this calculate the number of cubic
centimeters of acid corresponding to the pyridine contained
in the amount of liquor taken for the ammonia test. Subtract
this from the number of cubic centimeters of acid neutralized
in the ammonia test, and the result is the number of cubic
centimeters neutralized by the ammonia alone.
144
To detect possible errors in the distillation test for am-
monia, it is well to make a test on a pure ammonium salt.
For this purpose pure ammonium sulphate or chloride should
be dissolved in hot water, filtered and recrystallized. After
drying at 50° C., 4.5 to 5.0 grams are put in the distillation
flask with 175 cubic centimeters of water and 25 cubic centi-
meters of 30 per cent, caustic soda. The ammonia is received
in 100 cubic centimeters of normal acid. If the equivalent of
sulphate of ammonia found differs by more than 0.3 of I per
cent, from the 100 per cent, expected, the error should be cor-
rected. It will very likely be found in the standard solutions
used.
Free Ammonia.
Free ammonia is, by definition, that which can be distilled
off from liquor by boiling alone, without the use of alkali.
Its determination is made exactly as the determination of total
ammonia, described above, except that no caustic soda solu-
tion is used. The results are calculated in the same way and
by the same factors.
For greater convenience, when the utmost accuracy is not
desired, the determination of free ammonia may be made by
direct titration, as described below.
For weak liquors, 25 cubic centimeters of the liquor is
diluted with 100 cubic centimeters of water, and the solution
titrated with normal sulphuric acid, using methyl orange as
indicator. The indicator is gradually destroyed by something
in the solution. If the amount of acid needed is approximately
known, it is better to run in almost that amount, without adding
indicator, agitate the solution till most of the gas has gone,
add a few drops of indicator and bring to the end point. In
any case, if there is delay in reaching the end point, a couple
of drops of additional indicator must be added from time to
time.
For concentrated liquors 100 cubic centimeters are diluted
to 1,000 cubic centimeters, an aliquot of 100 cubic centimeters
145
taken and mixed with 100 cubic centimeters of water. Titra-
tion is performed as for weak liquors.
When results are desired in "ounce-strength," meaning the
ounces of sulphuric acid neutralized by the free ammonia in
i Imperial gallon, as previously denned, the calculation is per-
formed thus.
For weak liquors, multiply the number of cubic centimeters
of acid used by the factor 0.31443.
For concentrated liquors, multiply the number of cubic cen-
timeters of acid used by the factor 0.78608.
The results by direct titration check fairly well with those
by distillation, being usually a trifle higher. Where speed is
of more importance than high accuracy, the direct titration is
preferable.
Fixed Ammonia,
To the residue left in the distillation flask, after boiling off,
the free ammonia are added 100 cubic centimeters of water
and 25 cubic centimeters of 30 per cent, sodium hydroxide
solution. The ammonia is distilled off and received in 20
cubic centimeters of normal acid, diluted to 100 cubic centi-
meters. Calculation of results is the same as described under
"total ammonia."
Other Constituents of Liquor.
A. Pyridine: — 200 cubic centimeters of weak liquor, or 25
cubic centimeters of concentrated liquor diluted to 200 cubic
centimeters are neutralized with sulphuric acid of about 1 : 5
strength. The directions given for the direct titration of free
ammonia should be followed in reaching the neutral point.
Pyridine will now be combined as pyridine sulphate. Add
about 10 cubic centimeters of normal ammonium hydroxide,
or its equivalent, put in an ammonia distillation flask and distil
off as for total ammonia, into about 25 cubic centimeters of
normal sulphuric acid or its equivalent, diluted to 100 cubic
centimeters with water. Collect about 100 cubic centimeters
of distillate which will contain all the pyridine.
146
Put the distillate in an ammonia distillation flask with 10
cubic centimeters of normal sodium hydroxide solution and
distil into 50 cubic centimeters of water in a 250 cubic centi-
meter beaker. Collect 100 cubic centimeters of distillate which
will contain the pyridine together with considerable ammonia.
The beaker now contains 150 cubic centimeters. Add 6
drops of phenolphthalein indicator solution (5 grams per liter)
and run in normal sulphuric acid till the pink color is just
discharged. Read the burette and run in 0.13, cubic centimeter
more. (A test will show that with this volume of solution and
amount of indicator, the phenolphthalein color will be dis-
charged by 0.13 cubic centimeter less of normal acid than is
required to completely neutralize the ammonia when methyl
orange indicator is used.) Noting the reading of the burette,
add I drop of methyl orange and titrate to the pink color.
The amount of acid used to turn the methyl orange indicates
the amount of pyridine present. One cubic centimeter of acid
indicates 0.079 gram of pyridine, equivalent to 0.017 gram of
ammonia.
Acid Radicals.
The following methods are taken from the 1909 and previous
Reports of the Chief Inspector under the Alkali, etc., Works
Acts. They represent the result of work covering several
years, carried on in the laboratories of the Chief Inspector
in England.
Carbonate: — 10 cubic centimeters of liquor (more if dilute)
are diluted to 400 cubic centimeters and 10 cubic centimeters
of 2N ammoniacal solution of calcium chloride are added.
The whole is then heated for iT/2 to 2 hours in a water bath at
100° C., the flask being closed by a Bunsen valve. (That is
the flask is closed by a rubber stopper carrying a short
glass tube over which is slipped a piece of rubber tubing
plugged at its top end. Between the plug and the glass
tube, a slit about J4 mch long is made in the rubber tube.
Gases can escape but air from outside cannot enter.) The
precipitated calcium carbonate is filtered off, washed by de-
147
cantation, and dissolved in N/2 hydrochloric acid. The small
amount of calcium carbonate left on the filter paper is best
recovered by incineration and is added to the solution. The
excess of acid is titrated with N/2 sodium carbonate.
Sulphide: — 10 cubic centimeters of liquor are diluted to
500 cubic centimeters, acidified with hydrochloric acid, and
titrated with N/io iodine (starch indicator). The volume of
N/io iodine required determines how much liquor to take for
the actual determination of sulphide to follow. Ten cubic
centimeters (or more if the sulphide is apparently small in
quantity) are run into an excess of N/5 ammoniacal zinc chlo-
ride solution, diluted to about 80 cubic centimeters. The solu-
tion is warmed to coagulate the sulphide, filtered, and washed
with warm water of 40° to 50° C. temperature. The zinc
sulphide on the filter is washed into excess of N/io iodine,
acidified with hydrochloric acid (the last traces being washed
through the filter with cold dilute acid). After vigorous shak-
ing to complete the solution of the sulphide, the excess of
iodine is titrated with N/io thiosulphate.
Chloride: — 250 cubic centimeters of liquor are boiled to
expel sulphide, cooled, and made up to 250 cubic centimeters.
Dilute 10 cubic centimeters of this to 150 cubic centimeters,
add 25 to 50 cubic centimeters of hydrogen peroxide (3 per
cent, or "10 volume" solution, free from chloride), boil for
15 minutes, add 6 drops of a 10 per cent, solution of potassium
chromate, and continue the boiling 2 minutes. Should the
organic matter resist oxidation, more peroxide must be added
and the boiling continued with addition of potassium chromate
as before. Add a slight excess of sodium carbonate, re-boil
for I minute, filter, cool, make up to 250 cubic centimeters and
titrate an aliquot portion with N/io silver nitrate (potassium
chromate indicator) after bringing to the neutral point with
dilute nitric acid. A blank experiment is made with 10 cubic
centimeters N/io NaCl and the same volume of water, per-
oxide, and chromate, to determine the correction for traces of
chloride in the reagents used. (Twenty-five cubic centimeters
148
of peroxide should not contain more than the equivalent of 0.2
to 0.3 cubic centimeters N/io HC1.
Thiocyanate: — i. Ferrocyanide absent — 50 cubic centimeters
of the solution are treated with lead carbonate to remove sul-
phide and the lead sulphide and carbonate filtered off and
washed. To the filtrate, sodium bisulphite containing a little
free sulphur dioxide is added, followed by a distinct excess of
a 10 per cent, solution of copper sulphate. The solution is
allowed to stand 5 to 10 minutes at 70 or 80° C. to coagulate
the cuprous thiocyanate. It is then filtered and the precipitate
washed with boiling water till the washings give no coloration
with dilute potassium ferrocyanide. The residue is digested
at 30 to 40° C. with 25 cubic centimeters of a 4 per cent, solu-
tion of sodium hydroxide (free from chloride) and filtered.
To the cold filtrate are added 5 cubic centimeters of nitric acid
(50 per cent, strength and free from oxides of nitrogen) fol-
lowed by i cubic centimeter of a saturated solution of iron
alum. The solution is then filtered from separated organic
matter, if necessary, and titrated with N/io silver nitrate.
Thiocyanate: — 2. Ferrocyanide present — 50 cubic centime-
ters of the liquor are slightly acidified with sulphuric acid, and
ferric alum solution added in sufficient quantity to impart a
decided red coloration. The solution is then warmed to 60°
C., filtered from Prussian blue, and washed with water con-
taining sodium sulphate. The filtrate is finally treated as in
(i) above.
Sulphate : — 250 cubic centimeters of liquor are concentrated
to about 10 cubic centimeters on the water bath, 2 cubic centi-
meters of strong hydrochloric added, and the evaporation con-
tinued to dryness. The residue is extracted with water and
the filtered solution made up to 250 cubic centimeters. One
hundred cubic centimeters of this solution are acidified with
hydrochloric acid, heated to boiling and barium chloride added.
After standing over night, the precipitate is filtered off and
weighed.
Total Sulphur: — 50 cubic centimeters of liquor (100 cubic
centimeters if weak) are slowly dropped into an excess of
149
bromine (free from sulphur) covered by water moderately
acidified with hydrochloric acid. The oxidized solution is
evaporated to dryness on the water bath, filtered, cooled, and
made up to 250 cubic centimeters. One hundred cubic centi-
meters are precipitated with barium chloride in the usual way.
Sulphite and Thiosulphate : — Sulphur present as sulphate,
and thiosulphate, is found by subtracting from the total sul-
phur that present as sulphate, thiocyanate, and sulphide.
Ferrocyanide : — To 250 cubic centimeters of liquor, acidified
slightly with sulphuric acid, ferric alum solution is added in
sufficient excess to impart a deep red coloration. The mixture
is then heated to 60° C. and filtered, the filtrate being returned
to the filter if necessary until a little of it shows no blue color
after adding mercuric chloride. The precipitate is washed
2 or 3 times with water containing Na2SO4. The filter and
precipitate are then boiled for 5 minutes with 10 cubic centi-
meters of N sodium hydroxide, and the solution diluted to
150 cubic centimeters; 15 cubic centimeters of 3N magnesium
chloride are then added to the boiling solution slowly with
continual shaking in order to get a milky precipitate of
magnesium hydrate. This is then boiled again and 100 cubic
centimeters of boiling N/io mercuric chloride added and the
boiling continued for 5 to 10 minutes. The flask is then con-
nected to a condenser dipping into a receiver containing 25
cubic centimeters N sodium hydroxide. Thirty cubic centi-
meters of 4N sulphuric acid is run from a stoppered funnel
into the flask, and the contents distilled for 20 to 30 minutes,
when the whole of the hydrocyanic acid is obtained in the
receiver. The distillate is then titrated with N/io silver ni-
trate, after addition of a little potassium iodide.
Hydrocyanic Acid: — 50 cubic centimeters of the liquor are
added to an excess (50 to 100 cubic centimeters) of a satu-
rated solution of lead nitrate contained in the distillation flask
of the apparatus for determining free and fixed ammonia.
The mixture is distilled into 25 cubic centimeters of N sodium
hydroxide into which the exit tube of the condenser dips.
Thirty to 40 minutes gentle boiling, at which time about 50
cubic centimeters of liquid will have been distilled, is usually
sufficient. Frothing is liable to occur and the flask should be
heated therefore very carefully. At the end of the distillation
a current of air is passed through the apparatus for a short
time, to ensure the removal of the hydrocyanic acid. The
distillate is diluted to 400 cubic centimeters, a crystal of
potassium iodide added and the solution titrated with N/io
silver nitrate.
Rapid Method for Estimation of Carbon Dioxide and
Hydrogen Sulphide.
In following the operation of apparatus in which a portion
of the foul gases (carbon dioxide and hydrogen sulphide) are
driven off from the liquor by heat, it is desirable to be able to
determine those gases rapidly. For the purpose, the methods
of the Alkali Inspector given above are too time-consuming.
The following method is much more rapid and sufficiently
accurate for control purposes.
Ammoniacal Solution of Calcium Chloride: — Dissolve 100
grams of calcium carbonate with hydrochloric acid, after add-
ing a little water. Make alkaline with ammonia. Dissolve any
precipitate that forms with hydrochloric acid, and again make
alkaline. Continue this process of redissolving the precipitate
till the solution finally remains clear on adding an excess of
ammonia. Make the solution up to one liter.
Barium Hydroxide Solution: — Put 80 grams of good pure
barium hydroxide in 2 liters of water, and dissolve as much
of it as possible. After settling filter into another bottle.
Normal sulphuric acid and tenth-normal iodine solutions
are also needed.
In the process which is being examined, it is very likely that
the volume of the liquor will have changed between the inlet
and outlet of the apparatus by the addition of steam or water.
It is therefore more informing to report the foul gases present
as a ratio of the equivalent of the free ammonia also present.
A determination of the latter must therefore be made by direct
titration.
Free Ammonia : — Pipette 10 cubic centimeters of liquor, add
50 cubic centimeters of water, and titrate with normal sul-
phuric acid, with methyl orange indicator.
Carbon Dioxide and Hydrogen Sulphide: — In the distilling
flask of the "total ammonia" apparatus, put 200 cubic centi-
meters of water, and 10 cubic centimeters each of liquor, am-
moniacal calcium chloride, and strong (0.900 S. G.) ammonia.
In a 250 cubic centimeter flask to serve as a receiver, put 20
cubic centimeters of barium hydroxide solution, 10 cubic centi-
meters of strong ammonia and fill with water to one-half inch
from the bottom of the neck.
The object of adding ammonia to the distilling flask is to
keep the contents strongly ammoniacal during the distillation,
as otherwise some of the calcium carbonate formed will be
decomposed with loss of carbon dioxide. The object of add-
ing barium hydroxide to the receiver is merely to show the
possible presence of carbon dioxide in the distillate, which will
occur in the distillation is conducted too long and the flask
contents cease to be sufficiently ammoniacal. The barium hy-
droxide solution almost always shows a slight scum, due to
carbonic acid in the air, which must not be mistaken for car-
bonic acid distilled over.
Distil, slowly at first but with a larger flame as soon as the
liquid in the flask commences to boil, and continue the dis-
tillation for 5 minutes after increasing the flame. This length
of distillation will distil off the hydrogen sulphide without de-
composing the calcium carbonate. The residue in the flask
may be tested with lead acetate paper to show the removal of
hydrogen sulphide.
Transfer the liquid in the receiver to a 600 cubic centimeter
beaker and dilute to about 500 cubic centimeters. Add 3
drops methyl orange, acidify with hydrochloric acid, add 5
cubic centimeters of starch solution and titrate with tenth-
normal iodine.
Filter the liquid in the distilling flask through a close grained
filter, wash thoroughly with water, and dissolve the precipitate
in 15 cubic centimeters of normal sulphuric acid. The best
152
way to do this is to run the acid into the washed distillation
flask, to dissolve the precipitate which lodges there, and then
transfer it to a beaker into which is put the filter paper con-
taining the main portion of the precipitate. Stir well, boil,
cool and titrate back with ammonia solution, using cochineal
as indicator.
Since normal and tenth-normal solutions are used through-
out, the ratio of the normal acid used by the calcium carbonate
to that used in titrating the free ammonia, will show at once
what portion of the ammonia may be considered to be com-
bined with carbonic acid as the normal carbonate. The same
is true for the titration of hydrogen sulphide by iodine, with
allowance for the fact that the iodine solution is tenth-normal.
Ammonium Sulphate.
MOISTURE.
Approximately 10 grams of the salt are dried at 105° C. to
constant weight.
FREE ACID.
The dry salt from the moisture determination of approxi-
mately 10 grams of a fresh sample is dissolved in about 200
cubic centimeters of water. A drop or two of methyl orange
or sodium alizarin sulphonate is added and the free acid de-
termined by titration with N/io sodium hydroxide solution.
AMMONIA.
Ten grams are dissolved in water and diluted to i liter. An
aliquot of 100 cubic centimeter is taken for the determination
of ammonia. This is placed with 100 cubic centimeters of
water in a Kjeldahl distilling flask; 10 cubic centimeters of
30 per cent, caustic soda are added with a piece of granu-
lated zinc and the ammonia distilled over into 80 cubic centi-
meters of N/5 sulphuric acid. The excess acid is found by
titration, etc., using sodium alizarin sulphonate or cochineal
as indicator.
153
TARRY MATTER.
Fifty grams of salt are dissolved in cold water and filtered
on a Gooch crucible which is dried at 70° C. The tar is ex-
tracted with ether and the ethereal extract is evaporated in a
tared dish. The weight of dry extract is taken as total organic
matter.
NAPHTHALENE.
The above weighed tarry extract is dissolved in cold alcohol
and an equal weight of picric acid also in alcoholic solution
is added. The naphthalene picrate is then filtered off, dried
at 100° C. and weighed.
Naphthalene picrate X 0.3586 = naphthalene.
PYRIDINE.
To a filtered solution of 50 grams of sale in 150 cubic centi-
meters of water in a distilling flask is added about 20 cubic
centimeters of normal caustic soda, sufficient to make it slightly
alkaline, but not enough to decompose it. Distil into 100 cubic
centimeters of water. Nearly neutralize with hydrochloric
acid and redistil into 30 cubic centimeters of water until 70
cubic centimeters have come over. Make up the distillate to
a volume of 150 cubic centimeters, add 6 drops of phenol-
phthalein, and then run in normal acid till the pink color has
just disappeared. Then add 0.13 cubic centimeter more of
acid and read the burette. Add i drop of methyl orange and
titrate to a pink color. Each cubic centimeter of acid used
after adding the methyl orange equals 0.079 gram pyridine.
THIOCYANATES— PINK COLOR.
To a filtered solution of 100 grams of salt, copper sulphate
and sulphurous acid are added and the solution gently warmed.
After settling, the copper thiocyanate is filtered off and washed
free from copper salts as shown by testing the washings with
potassium ferrocyanide. The precipitate is then dissolved in
nitric acid, water added, and the solution boiled for several
154
minutes. The copper is determined in the solution as the
oxide by precipitation with sodium hydroxide; or by elec-
trolysis. The weight of copper X i-*974 equals equivalent
amount of NH4SCN.
FERRO FERRICYANIDE— BLUE COLOR.
One hundred grams of salt are dissolved in hot water and
filtered on a folded filter in a hot water funnel. Wash with
hot water until free from sulphates. The residue and filter
are put into a flask with about 50 cubic centimeters of water,
shaken and boiled to separate the residue from the filter as
much as possible. To the contents of the flask N/5<D sodium
hydroxide solution is added little by little until the blue is
entirely decomposed, which is hastened by having the contents
of the flask warm. While constantly shaking and heating, the
excess sodium hydroxide is titrated with N/5O acid. The
heating is quite necessary for even in the presence of an alkali,
the greenish color formed by the decomposition of the blue
lasts only a short time.
The end point is reached when the dark green color in the
solution first appears.
One cubic centimeter N/5O NaOH equals 0.001431 gram
Fe4Fe,(CY«)..
ARSENIC.
Dissolve 100 grams of salt in water and filter. The arsenic
will be on the filter as sulphide. Dissolve the sulphide by hot
digestion with sodium sulphide, using as little as possible. Fil-
ter and wash by stirring and pressure using slightly alkaline
H2S water. Evaporate filtrate to dryness in 25 to 50 cubic
centimeters hydrochloric acid (2 acid to I water) and add a
small crystal of tartaric acid. Precipitate the arsenic from
the cold solution with H2S, allow to settle for a short time,
filter on an asbestos felt and wash with acid of the same
strength. This separates the arsenic from any traces of an-
timony that may be present from hard lead and from traces of
tin which are sometimes present in distilled water which has
been condensed in a tin worm.
155
Place the felt with the arsenic sulphide in a beaker, digest
on a steam plate with red fuming nitric acid, dilute the solution
with \y2 parts of water and filter out the asbestos, and evap-
orate to dryness with o.i to 0.5 gram of sodium nitrate.
Dissolve the residue in 5 cubic centimeters of cold water
with 10 drops of HC1 and o.i gram tartaric acid. Filter into
a small beaker and wash with as little water as possible with
a fine jet.
Make slightly alkaline with ammonia. The solution should
be clear and not more than 1 1 cubic centimeters in volume.
Add 3 cubic centimeters magnesia mixture, make up to 20
cubic centimeters with strong ammonia and stir 5 minutes.
Allow to stand over night and filter on a small filter, aiding the
transfer of the precipitate within the filtrate. Wash free from
chlorine with a fine jet of ammonia (i to 3 of water) dry in an
oven, remove the salt and place filter in a porcelain crucible.
Add a few drops of acid ammonium nitrate solution (satu-
rated), char carefully and repeat treatment until paper is con-
sumed without any perceptible odor of arsenic. Transfer the
remainder of the precipitate and ignite at a full red heat to
constant weight. Weigh as Mg2As2O7.
Sampling.
A large shovelful is taken from each cart-load during the
unloading of a car, and put into a covered barrel. This
sample is broken down rapidly to ^-inch size, reduced by
quartering to 2 quarts, sealed up in an air-tight container and
sent to the laboratory. In the laboratory it is ground to a fine
powder preferably in a ball mill to avoid absorption of moist-
ure and carbon dioxide, and put in rubber stoppered weigh-
ing tubes.
i
DETERMINATION OF CALCIUM OXIDE.
Five grams of the finely ground lime is weighed into a 500
cubic centimeter graduated flask. Ten cubic centimeters of
alcohol are added, to prevent the later caking of calcium su-
156
crate, and the flask is filled up to the mark with a 10 per cent,
cane-sugar solution. It is shaken frequently over a 4-hour
period, or longer. The solution is then filtered, an aliquot of
100 cubic centimeters taken and titrated with normal hydro-
chloric acid, using methyl orange indicator.
Multiply five times the cubic centimeters of acid used by
0.02804. Divide by the amount of lime taken. The result is
the per cent, of calcium oxide.
CYANOGEN.
Moisture.
Dry 30 grams oxide for nine (9) hours at 50° to 60° C.
Extraction of Blue.
Grind the dried oxide so that it passes through an 8o-mesh
sieve. Weigh out 10 grams of this and introduce into a 250
cubic centimeter flask. Add 50 cubic centimeters of a 10 per
cent, caustic potash solution and let stand for 15 to 16 hours
at ordinary temperature, shaking frequently. At the end of
this time, make up to 225 cubic centimeters (5 cubic centi-
meters for the oxide). Shake vigorously and filter through
a dry filter. Take 100 cubic centimeters of the filtrate and
run it into a boiling solution of ferric chloride — 50 cubic cen-
timeters. This ferric chloride solution consists of 60 grams
ferric chloride and 100 cubic centimeters HC1 made up to
1,000 cubic centimeters. After the blue settles a little, filter
and wash with boiling water, until the blue, together with the
filter paper is put into a beaker and 25 cubic centimeters of
the caustic potash solution is added, and, after complete de-
composition, made up to 250 cubic centimeters and then filtered
through a dry filter. Take 100 cubic centimeters of this fil-
trate, acidify with 10 per cent, sulphuric acid (test with lit-
mus) and add excess of 10 cubic centimeters acid. Titrate
with standard zinc sulphate solution, the operation being the
same as in the standardization of the zinc solution. From the
number of cubic centimeters zinc sulphate used, the value of
this in prussiate can be calculated.
157
Calculation. — Multiply your standard by number of cubic
centimeters ZnSO4 used, and divide by 1.6, multiply this re-
sult by 100. This gives per cent, of Prussian blue as
K4Fe(CN)6 in dry sample.
This result multiplied by 100 minus the moisture per cent,
gives the result in terms of the undried oxide.
ZINC SULPHATE SOLUTION.
Weigh out 10 grams zinc sulphate C. P. and make up to i
liter, after adding 10 cubic centimeters concentrated sulphuric
acid.
POTASSIUM FERROCYANIDE SOLUTION.
Weigh out exactly 5 grams potassium ferrocyanide (C. P.
and with exact quantity of water of crystallization. If this
is more or less, a correction has to be made). Make up to
250 cubic centimeters.
STANDARDIZING THE ZINC SOLUTION.
Measure out 25 cubic centimeters of the ferrocyanide solu-
tion into a beaker. Add about 50 cubic centimeters of water
and acidify with 10 cubic centimeters of a 10 per cent, sul-
phuric acid solution. Now from a burette run in the zinc
solution.
As an indicator, use a 3 per cent, solution of ferric alum,
using Schleichner & Schnell's drop reaction paper No. 601.
One drop of the ferric alum solution is brought on to the
paper, and near this spot a drop of the solution being titrated
is placed, so that by extension the two spots just touch each
other. The end point of the titration is reached when the blue
coloration at the point where the two drops meet does not
appear for the space of I minute. From the number of cubic
centimeters of zinc 'sulphate solution used, the value of this
in prussiate can be calculated.
In titrating the oxide solution, acidify the 100 cubic centi-
meters with 10 per cent, sulphuric acid, after adding methyl
orange No. 3 to the solution, and add an excess of 10 cubic
ii
IS8
centimeters acid. Titrate with the standard zinc solution,
the operation being the same as the standardization of the zinc
solution.
The original Knublauch method involved the use of copper
sulphate.
The Feld-Witzeck Method.
Two grams of the dried and finely pulverized oxide are
taken and titrated for 5 minutes in a glass mortar with.i cubic
centimeter of normal solution of ferrous sulphate and 5 cubic
centimeters of eight times normal solution of caustic soda.
Then 50 cubic centimeters of three times normal solution of
magnesium chloride are added with constant stirring, and the
whole is washed into a flask — the volume of liquid being
brought to about 220 cubic centimeters. After boiling for 5
to 10 minutes, 100 cubic centimeters of boiling decinormal
solution of mercuric chloride are poured into the boiling liquid,
and the boiling continued for 10 minutes. The flask is then
connected with the condenser, 30 cubic centimeters of four
times normal sulphuric acid are added, and the liquid is dis-
tilled for 20 to 30 minutes. The distillate is collected in 20
cubic centimeters of twice normal solution of caustic soda. If
it is cloudy, 0.5 gram of lead carbonate is added to it in a
measuring flask, which is filled to the mark, and an aliquot
portion is taken for the titration, after the precipitate has been
filtered off.
The titration is carried out according to Liebig's method
with decinormal solution of silver nitrate and the addition of
"5 cubic centimeters of one-fourth normal solution of potassium
iodide. The appearance of a yellowish milky cloudiness indi-
cates the end of the reaction. (Journal of Gas Lighting &
Water Supply, Aug. 3, 1915, p. 244.)
Apparatus for Distillation. — A round bottom flask is pro-
vided with a double bored rubber stopper which contains a
separatory funnel and distilling column. The latter is con-
nected with a condenser which dips into an Erlenmeyer flask
159
also provided with a double bored rubber stopper, the second
hole is connected with a 3-bulb tube containing sodium hy-
droxide. ( Allen- s Commercial Organic Analysis, Vol. VII,
P- 521-}
The Committee recommends the use of the Feld-Witzeck
Method.
CHAPTER HI.
IMPURITIES IN GAS.
DETERMINATION OF HYDROGEN SULPHIDE.
The hydrogen sulphide is determined by leading the gas
through a suitable absorption apparatus containing a solution
of lead nitrate. The resulting lead sulphide is filtered off,
oxidized in a porcelain crucible with nitric acid, treated with
a drop of sulphuric acid, evaporated to dryness, ignited and
weighed.
For works control where great accuracy is second and speed
first consideration, the H2S burette is the most widely used
method and gives within small errors best results, and can be
recommended as sufficiently accurate for all practical pur-
poses.
The apparatus employed is shown in Fig. 34. It consists
of a burette provided at the top with a 2- way and at the
bottom with a i-way cock, communicating at top through one
of the outlets with a 10 cubic centimeter glass stoppered cyl-
inder graduated into i/io cubic centimeter. There are only
two graduations on the burette proper, one at the 100 cubic
centimeter mark, and the other 50 millimeters from the bottom
cock, dividing the remaining space into two divisions of about
5 cubic centimeters and 10 cubic centimeters respectively. A
levelling bulb is attached to the lower cock at E, and the burette
mounted on a stand as indicated.
Chemicals.
The following chemicals are necessary :
1. Standard Iodine Solution. — One cubic centimeter of this
solution should contain 0.0017076 gram iodine, which is equiv-
alent to loo grains of sulphur eted hydrogen per 100 cubic feet
of gas.
2. Starch Solution. — Rub into a thin paste about I teaspoon-
ful of wheat starch with a tablespoonful of water. Pour into
a pint of boiling water, stir, allow to stand until cold, and
pour off the clear solution for use. Make a fresh solution
every few days.
FIG. 34.
1 62
t
To Make Analysis.
Fill levelling bulb L with starch solution and turn cocks so
that on raising the levelling bulb the starch solution will fill
the burette and run out through the gas inlet tube A. Close
lower cock C, and attach rubber tube through which the gas
to be tested is passing to inlet tube A. Open lower cock, and
lower levelling bulb until the starch solution just passes the
100 cubic centimeter mark on the stem of the burette. Close
lower cock, then close top cock F, and disconnect from gas
supply. Open lower cock and bring starch solution to 100
cubic centimeter mark by raising levelling bulb, then close
lower cock and open top cock to air momentarily to obtain at-
mospheric pressure in the burette. Close top cock and by open-
ing lower cock and lowering the levelling bulb draw the starch
out of the burette down to the 10 cubic centimeter mark. Close
lower cock, place clip on rubber tubing near E, and disconnect
levelling bulb from £.
We now have 100 cubic centimeters of gas measured at
atmospheric temperature and pressure, under a negative pres-
sure.
Fill graduated cylinder C with standard iodine solution,
noting reading on same. Admit iodine solution into the bu-
rette very gradually through F, shaking well between each ad-
dition. Continue until the starch solution assumes a faint, but
permanent blue color.
Note reading on graduated cylinder, which subtracted from
previous reading gives amount of solution used. This multi-
plied by 100, gives directly number of grains of hydrogen
sulphide per 100 cubic feet of gas.
Precautions.
I. It will be found that even with gas entirely free from sul-
phureted hydrogen an appreciable amount of iodine solution
will be required to color the starch solution a permanent blue.
Therefore a certain constant, previously determined on each
fresh bottle of starch solution, should be subtracted from all
i63
readings. In order to determine this constant, suck starch
solution into the burette up to the 10 cubic centimeter mark,
this being the amount used in each determination, close lower
cock and carefully drop into the burette iodine solution from
the cylinder, shaking between each addition, until the starch
solution assumes a permanent blue color. Note amount of
iodine added, which will be about 0.2 cubic centimeter to 0.3
cubic centimeter and subtract this from total amount of iodine
solution required in each determination.
2. The blue color must not be confused with the opalescent
milky appearance due to the separation of free sulphur, nor
with a red color which will disappear on shaking.
3. For extremely accurate work, introduce a correction fac-
tor for temperature and pressure, bringing the gas to 60° F
and 30".
In special cases where the highest accuracy is required and
time can, therefore, be no factor, the following method is the
most suitable :
The gas to be tested is first purified from such impurities as
may interfere with the work, such as tar, by passing it through
a U-tube filled with cotton and then into a gas wash bottle
containing an ammoniacal solution of silver nitrate. (It is best
to use two bottles in series to prevent any H2S to go by when
the first bottle should become saturated by a high H2S content
in the gas, stopping the operation when the second solution is
showing precipitate of silver sulphide.) The ammonia ab-
sorbed by the gas from the train is removed by another bottle
containing H2SO4 before entering the meter. Where insuffi-
cient gas pressure exists it is best to use suction to pull the
gas through. The solution and precipitated Ag2S etc. is next
transferred to a beaker and filtered and washed. The silver
acetylene formed is next decomposed by filling the filter with
diluted HC1, forming silver chloride and acetylene ; again wash
with water and remove the silver chloride with dilute NH^OH
and again with water.
The filter and contents are next placed in a Rose crucible,
dryed and burned. After all the filter paper has been burned
164
and the sulphide roasted, the silver is reduced in a stream of
hydrogen to metallic silver. From the weight of the metallic
silver the H2S is calculated by multiplying the weight with
0.1578 or with 0.14875 for sulphur.
FIG. 35.
Another quicker although not quite as accurate method has
been in use in various modifications. It is based on the method
of determining sulphur in steel. The gas freed from tar by
passing it through cotton is bubbled through an ammoniacal
solution of cadmium chloride contained in a gas washing
bottle using a graduated aspirating bottle for measuring the
gas or a meter. The operation is as follows :
To the gas outlet by means of a short rubber tube connect
a U-tube filled with cotton, connect this with two gas washing
bottles (200 cubic centimeters capacity), containing 50 cubic
centimeters of an ammoniacal solution of cadmium chloride, in
series. If a meter is used for measuring the. gas another bottle
containing dilute sulphuric acid, to remove the ammonia from
the gas before entering the meter, must be placed behind the
absorption bottles. This can be omitted where a graduated
aspirating bottle is used. This bottle (see Fig. 35) is gradu-
ated by filling it with water to a mark scratched on the glass L
in the stopper at the top, the water is next drawn out through
the bottom stopper also fitted with a glass L and closed with
a piece of rubber tubing and pinch-cock. 3,537.5 cubic centi-
meters = to y% cubic foot of the water are drawn off and the
bottle marked. This is best accomplished by having a 2-hole
stopper at the bottom, the second hole being fitted with a glass
tubing bent short at right angles and reaching to the top.
The bottle being perfectly level, the second mark is made on
this tube insuring more accurate measuring. Where a meter
is used from o.i to 0.15 cubic foot of gas are passed. In both
cases the gas should be passed at a very slow speed, not more
than 0.5 cubic foot per hour.
The contents of the washing bottles are next transferred to
a 600 cubic centimeter beaker, the bottles first washed with dis-
tilled water and then with a little dilute hydrochloric acid, suffi-
cient dilute HC1 added to the beaker to make acid, indicated by
clearing of solution, starch solution added and titrated with
standardized iodine solution, and the H2S calculated from the
iodine used.
Qualitative Test.
For qualitative test the following method is in general use :
A strip of white filter paper is dipped in a solution containing
5 per cent, by weight of lead acetate, the excess solution being
removed from the test paper with a blotter. The paper is ex-
posed while moist for I minute to a current of gas flowing at
the rate of approximately 5 cubic feet per hour in an apparatus
as shown in Fig. 31 and described below, or in other similar
apparatus.
1 66
The gas may be considered free from hydrogen sulphide if
the paper thus exposed is not distinctly darker than another
paper moistened with the same solution but not exposed to
the gas.
! i
! 1
V
fpn
i j
TT
FIG. 36.— Apparatus for exposing test paper.
The apparatus for exposing the paper as shown in Fig. 36
is made from a cylindrical gas chimney 8 inches long, and 1^4
inches in diameter. The pillar of a gas burner from which the
lava tip has been removed is inserted through the lower stop-
per, and- a small glass, i to i^ inches in diameter is sup-
ported above the pillar to prevent the gas from impinging
directly on the test paper. The watch glass may be supported
on three glass pegs, ^ to i inch high, being held in place with
small bits of wax. The gas is burned from an ordinary open
:67
flame burner on the upper stopper, this burner being so selected
that it will pass 5 cubic feet per hour at the ordinary pressure
of the gas supply. The test paper is hung on a glass hook so
that it is held midway between the watch glass and the bottom
of the upper stopper.
This apparatus may be attached permanently to a wall
bracket, or a Bunsen burner may be inserted through the lower
stopper in place of the pillar so that the apparatus can con-
veniently be attached at any outlet with a rubber hose.
AMMONIA.
Methods of Operation.
The apparatus as shown in Fig. 37 consists of two all glass
modified Woulff bottles. These should be placed before the
governor and meter if the ammonia determination is made in
connection with the sulphur determination.
Place in the absorption apparatus an accurately measured
portion (about 25 cubic centimeters) of a standard solution of
sulphuric acid prepared as directed below, and add 2 drops of
the indicator solution. The acid should be measured from a
pipette or a burette and may then be diluted with the distilled
water until the volume is obtained which gives the best opera-
tion with the particular apparatus in use. Connect the appar-
atus writh the gas supply, and with a meter on the outlet of the
bottle pass the gas to be tested, at the rate of 0.5 to 0.6 cubic
foot per hour, for 2 to 5 hours, according to conven-
ience and accuracy required. Somewhat greater accuracy is
secured by the longer test. When the requisite amount of gas
has passed, the supply is shut off and the color of the solu-
tion noted to determine whether the acid has been neutralized,
as shown by the indicator. If neutralized, add more H2SO4
to make slightly acid. The acid remaining unneutralized is
determined as follows : The content of the apparatus is rinsed
into a beaker with distilled water, using the smallest amount
i68
possible to secure complete removal of the acid, and the solu-
tion is titrated with a standard solution of sodium hydroxide.
A solution of sodium alizarin sulphonate is recommended
as an indicator. The solution of sodium alizarin sulphonate
for use is made by dissolving I gram of the material in 100
cubic centimeters of water and filtering off the undissolved
FIG. 37.
portion. In titrating, the end point is reached when the color
changes from greenish yellow to light brown. The color
further changes to red, but the first change is the proper one
for this work. The change is sharp.
Preparation of Solutions.
The sulphuric acid may be conveniently made of such
i6g
strength that I cubic centimeter neutralizes approximately
0.005 gram of ammonia, and its exact strength is determined
by standardization. To 2 liters of distilled water add between
1.25 and 1.50 cubic centimeters of pure concentrated sulphuric
acid and mix thoroughly by shaking. This solution must be
carefully preserved in a glass stoppered bottle to avoid con-
tamination and evaporation. For the standardization of the
acid a 50 cubic centimeter portion is accurately measured into
a 400 cubic centimeter beaker, diluted to 250 cubic centimeters
and treated with 10 per cent, barium chloride solution in the
manner already given. The weight of barium sulphate (in
grams) obtained by this process is multiplied by 2.25 and then
divided by the number of cubic centimeters of solution taken
as sample. The result is then expressed in grains of ammonia
equivalent to I cubic centimeter of the acid.
The sodium hydroxide solution for titrating the excess of
the acid is prepared by dissolving approximately 1.8 grams of
sodium hydroxide in 2 liters of water and mixing thoroughly.
To obtain the ratio of the acid to the alkali, measure out the
same amount of acid as is ordinarily titrated in a determina-
tion and add distilled water until the volume of solution is
about equal to that obtained in washing out the apparatus
after a determination, add 2 drops of indicator solution and
complete the titration with the alkali. For convenience the
strength of the alkali may be made equivalent to the acid by
dilution or further addition of alkali.
TOTAL
The referee's form of apparatus is recommended on account
of its wide use and general ease of manipulation. The ap-
paratus is shown in Fig. 38.
The entire apparatus consists of a pressure governor, U
water gauge, meter and sulphur apparatus; these being con-
nected in the order given. If the gas used for the sulphur tests
is also used for the ammonia test, the ammonia absorber is
connected between the source of the gas supply and the pres-
sure governor. For connecting the various parts of the appa-
ratus rubber tubing is not satisfactory. It is usually most con-
venient to make permanent connections from governor to
gauge, gauge to meter, and meter to burner; these can be of
glass tubing with rubber connections wired on, except the
-.
FIG. 38.
connection of meter to burner. For the latter it is best to
braze or screw a metal tube to the burner inlet (about 6 to 8
inches is a convenient length) so that if the burner strikes
back during a test the connection is not broken at the base of
the burner and gas allowed to escape or take fire at this point.
The meter and governor used may be of either the wet or dry
type. 'The usual precautions as to levelling and proper adjust-
ment should, of course, be observed. The pressure on the
governor should be so adjusted once for all that when the gas
is turned on full at the supply cock the burner will pass gas
at the desired rate.
I/I
The connection between meter and burner, as well as the
meter itself, should be frequently tested to show the absence
of leaks. Any leaks, even very small ones, may cause appre-
ciable errors in the test, since the rate of gas consumption is
small.
Method of Operation.
After all connections and adjustments of the apparatus have
been made the gas should be burned from the apparatus for
several hours to saturate the meter and governor water and
to purge the connections. Before each test the line may be
purged in this way by burning the gas for about a half-hour, a
burner which will pass 5 cubic feet or more per hour being
substituted for the regular test burner.
When the line is thus purged, the regular burner is put in
place and ammonium carbonate placed on the burner. As
much ammonium carbonate is used as will find place about the
burner pillar. The ammonium carbonate should be in large
lumps which have been freed from effervescent portions. It
is usually desirable to rinse out condenser and chimney tubes
just before starting the test, in order to prevent dust which
might have collected there between the tests from contami-
nating the condensate. When all parts, including the "flask to
collect the condensate, are in place, the trumpet tube is set
over the burner and quickly connected with the condenser,
the meter reading being noted at the instant the trumpet tube
is put in place. This reading and the time, meter, tempera-
ture, barometer and manometer readings are recorded in the
test record.
The gas is burned at y2 cubic foot per hour.
If the sulphate is to be determined gravimetrically, it is gen-
erally desirable to burn at least 2.y2 or 3 cubic feet of gas for
a test.
When it is desired to burn more than 3 cubic feet of gas
for a test, it is necessary to replenish the supply of ammonium
carbonate. To do this the gas is shut off and the trumpet
tube allowed to cool so that it may be handled comfortably.
A fresh supply of carbonate is then added, the burner re-
lighted, and the trumpet tube replaced quickly. If more than
a few thousandths of a cubic foot of gas are burned with the
trumpet tube off, the amount so burned should be deducted
from the total used for the test. A fresh supply of carbonate
must be added in this manner after every 3 cubic feet of gas
burned in the Referee's apparatus.
When sufficient gas has been burned, the supply is cut off
and the apparatus allowed to cool. The time, meter reading,
meter temperature, and barometer are recorded again at the
close of the test. The trumpet tube is then washed once and
the condenser four times. Each portion of wash water is 50
cubic centimeters and is added all at once to thoroughly flush
the condenser.
The sulphate in the condensed liquid and wash water is de-
termined by precipitation with barium chloride. From sulphate
found and corrected volume of gas burned, the sulphur con-
tent of the gas (in grains of sulphur per 100 cubic feet of gas)
is calculated.
Determination of Sulphate in the Solution Obtained.
In the more common procedures for the gravimetric sul-
phate determination, the precipitation of the barium sulphate
is made in nearly neutral solution. This method may be used
as follows:
To the solution which is diluted or concentrated to about
300 cubic centimeters add 2 or 3 drops of paranitrophenol or
methyl orange solution and neutralize with hydrochloric acid,
adding this solution dropwise, and finally add 2 cubic centi-
meters of the i : i acid in excess. Heat to boiling, add 10
per cent, barium chloride solution, boil 5 minutes, allow to
stand on a steam bath for a half-hour or longer, filter through
a good close-grained paper, and wash with hot water until a
few drops of filtrate collected in a test-tube no longer form a
precipitate with silver nitrate. In a weighed platinum crucible
char the paper with low Bunsen flame and finally ignite until
the precipitate appears white. Cool the crucible in a desic-
173
cator and weigh. The precipitation when made in the pres-
ence of a fixed amount of acid is always affected in equal
degree by the solubility of the barium sulphate in the acid.
Under the conditions given, the loss from this source is negli-
gible for the present work.
DETERMINATION OF NAPHTHALENE IN GAS.
Absorption of Naphthalene by Picric Acid.
Pass the gas to be tested first through N/i H2SO4, next
through an empty bottle, then through three bottles each con-
taining 100 to 150 cubic centimeters of saturated picric acid
solution and excess of undissolved picric acid, (2) and finally
through a gas meter for measurement. Stop the operation
when a naphthalene picrate precipitate begins to appear in the
second picric acid wash bottle.
Preparing Benzol Solution of Naphthalene-Pier ate
and Picric Acid.
Transfer the picric acid solution and precipitate to a liter
separatory funnel, the residues being washed in with naphtha-
lene-free benzol. Shake gently the funnel contents until the
precipitate is completely dissolved in the benzol. Reject the
aqueous layer and draw the benzol solution into a 250 cubic
centimeter measuring flask. Make up to the mark with benzol
and thoroughly mix.
Determination of Total Picric Acid.
Titrate 50 cubic centimeters of this solution — preferably in
a 200 or 250 cubic centimeter separatory funnel for shaking is
necessary — with N/5 NaOH using methyl red as indicator.
This titrates both the free and combined picric acid.
If T = cubic centimeters N/5 NaOH required for this
total titre.
Then $T = cubic centimeters N/5 NaOH required for total
titre of the whole solution.
(To prepare methyl red indicator, dissolve 2 grams methyl
12
174
red in I liter of a mixture of two parts grain alcohol and one
part water.)
Determination of Free Picric Acid.
The free picric acid present is determined by the following
procedure :
1 200
From a burette draw —=^- cubic centimeters of the ben-
zol solution into* a 100 cubic centimeter flask and evaporate
to dryness to remove the benzol, proceeding carefully accord-
ing to the following directions. The flask is placed in a hot
water bath and a current of air passed over (not in) the
benzol solution, at no time allowing the level of the hot water
to be above the level of the benzol solution. The flask should
be gently shaken during the evaporation to keep the walls
moistened and to avoid overheating any part. (4) Keep the
flask about I minute in the hot water after the residue ap-
pears dry, then remove, but continue the air current until the
odor of benzol can no longer be detected.
Dissolve the residue in the flask with 10 cubic centimeters
of 95 per cent, alcohol, heating gently if necessary, then pre-
cipitate the naphthalene-picrate by adding distilled water
slowly, with agitation, until the volume is exactly 100 cubic
centimeters. The temperature of this solution must be cooled
to 20° C. — in no case more than 2° higher or lower.
Filter through a dry filter into a 100 cubic centimeter cyl-
inder and titrate 90 cubic centimeters of the filtrate with N/5
NaOH using methyl red as indicator. The cubic centimeters
N/5 NaOH taken divided by 0.9 give the titre required for
the free picric acid in — =- cubic centimeters of the original
benzol solution.
If F = cc. N/5 NaOH required for this ^? cc.
250
Then F X 1200 = NaOH required for the free picric
T acid in the whole benzol solution.
Calculation of the Naphthalene from the Picric Acid Titres.
The difference between the total titre and the free acid titre
is the titre of the picric acid combined as naphthalene-picrate,
and this latter titre, multiplied by its naphthalene equivalent,
gives the grams naphthalene in the gas sample taken, as fol-
lows:
Grams naphthalene
Free acid equivalent to i cc.
Total titre titre N/s NaOH
I 5 T -- (F X 1200) X 0.0256 — Grams n aphthalene in
T gas sample.
or, simplified o.oo53T (24 — F) = grams naphthalene in gas
sample, and - — — grams naphthalene per cu.
cu. ft. gas taken
ft. gas. which X 15.43 — grains per cu. ft.
Notes on the Method,
1 I ) The reactions involved in the method are the following :
Naphthalene Picric acid Naphthalene picrate
C10H8 f C6H2(N02)3OH = C6H2(N02)3OH.C10H8+H20
Picric acid Sodium picrate
C6H2(N02)3OH " = C H (NO) ONa H
C6H2(N02)3OH.C10H8 + NaOH =
C6Ha(N02)3ONa + C10H8 + H2O.
(2) To absorb the naphthalene completely the picric acid
solution must be fully saturated, and to insure this an excess
of crystals must be present.
(3) The reason for taking cubic centimeters of the
benzol solution for the free picric acid test is that this is the
quantity which contains the right amount of total picric acid
(i.i grams) to saturate the 100 cubic centimeters of solution
to which it is finally made up, and this saturation is essential
to prevent decomposition of the naphthalene picrate present
at the stated temperature (20° C.).
176
(4) Naphthalene picrate is easily decomposed by heat,
evolving naphthalene and leaving behind free picric acid.
Reagents— N/5 NaOH.
Saturated picric acid solution of known strength (100 cubic
centimeters picric acid should be equivalent to 28-35 cubic
centimeters N/5 NaOH).
Methyl red or lacmoid indicator.
Standardising, of the Picric Acid.
Filter 500 cubic centimeters of strongly saturated picric acid
solution. Take 100 cubic centimeters of filtrate and titrate
against N/5 NaOH, using methyl red or lacmoid indicator.
Between 28 and 35 cubic centimeters N/5 NaOH should be
required. Let titre equal "A."
Test.
Wash 15 to 50 cubic feet of gas through the remaining 400
cubic centimeters of picric acid. The gas should first pass
through a dilute H2,SO4 solution, next an empty bottle and then
through at least two picric acid wash bottles. The gas should
be washed at the rate of i or 2 cubic feet per hour.
As rubber absorbs naphthalene the connections between
bottles, and to the supply pipe, must be so made that little or
no rubber is exposed to the gas. (Glass to glass.)
Determination.
Mix the picric acid solution and filter. Reject the first 50
cubic centimeters. Take the next 100 cubic centimeters and
titrate against N/5 NaOH. Let titre equal B. Let C equal
the N/5 NaOH equivalent of naphthalene in one- fourth of
gas used. Then A — B = C.
One cubic centimeter N/5 NaOH equals 0.0256 gram naph-
thalene.
Therefore : 4 x c x 0.0256 equals grams naphthalene in gas
tested.
177
For Example.
In a test, 69 cubic feet of gas were washed. Titre A re-
quired 31.8 cubic centimeters N/5 NaOH. Titre B required
30.4 cubic centimeters N/5 NaOH.
31.8 — 30.4 equals 1.4.
4 x 1.4 x 0.0256 equals 0.14336 grams naphthalene.
0.14336 divided by 69 equals 0.00208 grams C10H8 per cubic
foot gas used.
Remarks.
Grams naphthalene per cubic foot x 1543 = grains naph-
thalene per loo cubic feet.
(O ^ T cS
p 7 — - — - grains naphthalene per 100 cu. ft.)
A picric acid solution containing 12 grams per liter picric
acid is saturated at 15° C. though it can be colled several
degrees lower without separation of picric acid. If the latter
separation takes place during the test a serious error may re-
sult, consequently the solution must not be too strong for the
temperature to which it may be exposed and a 12 grams per
liter solution is recommended for ordinary temperature (15°
to 25° C.).
Since the naphthalene content is calculated from a small
difference between two large titres the latter must be carefully
and exactly performed. The best indicator appears to be
methyl red.
DETERMINATION OF CYANIDE IN GAS.
In each of a series of three Muencke gas washing bottles
are placed 20 cubic centimeters of a strong solution of caustic
soda (1:3), to which is added 50 cubic centimeters of sus-
pended ferrous hydroxide. The ferrous hydroxide used is
prepared by adding 40 cubic centimeters of the caustic solu-
tion to 60 cubic centimeters of a 10 per cent, solution of fer-
rous sulphate, allowing the precipitate of ferrous hydroxide
to settle, decanting off the solution containing sodium sulphate,
and making the volume of suspended ferrous hydroxide up to
150 cubic centimeters with water. About 5 cubic feet of gas
are passed for each test, at the rate of approximately 2.5 cubic
feet per hour. The contents of the three bottles are then trans-
ferred to a flask, boiled for 15 minutes, allowed to cool, and
filtered. The filtrate is made up to 500 cubic centimeters and
an aliquot part 100 cubic centimeters acidulated with sulphuric
acid, an excess of ferric alum added and the precipitated
Prussian blue collected and washed until free from sulphates.
The precipitate with the filter is at once placed in an evap-
orator, water added, and the contents heated nearly to boiling,
the amount of Prussian Blue being then directly determined by
titrating with N/5O NaOH. (The end point is reached when
the last trace of blue disappears.)
If 5 cubic feet of gas is used in the test then :
i cubic centimeter N/NaOH = 2.3315 pounds of K4Fe-
(CN)..3H,0,
or, i cubic centimeter N/NaOH = 2.8660 pounds of Na4Fe-
(CN)6.I2H2O per 10,000 cubic feet of gas.
i cubic centimeter N/5O NaOH = 0.04663 pound of K4-
Fe(CN)6.3H20,
or, i cubic centimeter N/5O NaOH = 0.05732 pounds of
Na4Fe(CN)6.i2H2O per 10,000 cubic feet of gas.
DETERMINATION OF CO2 IN GAS.
(See under gas analysis.)
DETERMINATION OF CS2 IN GAS.1
The gas is first passed through cotton to remove tar and
then dried by passing it over calcium chloride and then through
three wash bottles containing a strong solution of NaOH cov-
ered with an ethereal solution of triethylphosphine until a red
coloration appears in the third bottle. The gas should be
passed very slowly, not over 0.5 cubic foot an hour and not
more than 2 cubic feet of gas should be used. After the
1 This method although not in general use is very promising and worthy of con-
sideration for further use.
179
third bottle becomes red, the contents of the three bottles are
transferred to a beaker and filtered through a weighed filter
paper, washed and dried. The weight of the (CBH2)3PCS2
multiplied by 0.392 gives the weight of CS&.
DETERMINATION OF IRON CARBONY!^
Iron carbonyl may be determined by passing the gas through-
concentrated nitric acid or bromine water and determining the
iron in solution (due to the decomposition of the carbonyl) by
first evaporating with the addition of H2SO4 until white fumes
of acid are coming off, then dilute with water, reduce with
zinc, and titrate with standard permanganate. This amount
of iron multiplied with 3.5 gives the weight of iron carbonyl.
Since the carbonyl is present in very minute quantities large
volumes of gas (at least 100 cubic feet) have to be treated
to obtain any tangible results.
1 This method although not in general use is very promising and worthy of con-
sideration for further use.
CHAPTER IV.
TESTS OF TAR PRODUCTS AND LIGHT OILS.
i. CRUDE: GAS BENZOLS.
a. Bulb Distillation.
APPARATUS.
FIG. 39.
Flask : The flask used shall be the standard Engler flask,
as described in the various standard works upon petroleum,
such as Redwood, Holde, etc.
"Engler employs a globular flask 6.5 centimeters in diam-
eter, with a cylindrical neck 1.6 centimeters in internal diameter
and 15 centimeters in length, from the side of which a vapor
tube 10 centimeters in length extends at an angle of 75°
downwards to the condenser. The junction of the vapor tube
with the neck of the flask should be 9 centimeters above the
surface of the oil when the flask contains its charge of 100
cubic centimeters of oil. The observance of the prescribed
dimensions is considered essential to the attainment of uni-
formity of results." (Redwood, 3rd Ed., Vol. II, p. 205, 1913.)
The flask shall be supported in a ring of asbestos having an
opening iJ/£ inches in diameter in its center.
The flask, burner, etc., shall be surrounded by a shield.
Condenser: The condenser shall consist of a tube of thin
glass 24 inches in length, set at an angle of 75° with the flask
surrounded by a water-jacket of the through type.
The thermometer shall conform to the following require-
ments :
The thermometer shall be made of resistance glass of a
quality equivalent to suitable grades of Jena or Corning makes.
It shall be thoroughly annealed. It shall be filled above the
mercury with inert gas which will not act chemically on or
contaminate the mercury. The pressure of the gas shall be
sufficient to prevent separation of the mercury column at all
temperatures of the scale. There shall be a reservoir above
the final graduation large enough so that the pressure will not
become excessive at the highest temperatures. The thermom-
eter shall be finished at the top with a small glass ring or
button suitable for attaching a tag. Each thermometer shall
have for identification the makers' name, a serial number, and
the letters "A. S. T. M. DISTILLATION."
The thermometer shall be graduated from o° to 400° C. at
intervals of i° C. Every fifth graduation shall be longer than
the intermediate ones, and every tenth graduation beginning at
zero shall be numbered. The graduation marks and numbers
shall be clear-cut and distinct.
The thermometer shall conform to the following dimensions :
182
Total length, mm 385 maximum
Diameter of stem, mm 7, tolerance 0.5
Diameter of bulb, mm 5 minimum, and shall not
exceed that of the
stem
Length of bulb, mm 12.5, tolerance 2.5
Distance o° to bottom of bulb 30, tolerance 5
Distance o°-4OO° 295, tolerance 10
The accuracy of the thermometer when delivered to the
purchaser shall be such that when tested at full immersion the
maximum error from o°-2OO° C. shall not exceed 0.5° ; 200°-
300° C., it shall not exceed i° C.; 3OO°-375° C., it shall not
exceed 1.5° C.
The sensitiveness of the thermometer shall be such that
when taken at a temperature of 26° C. and plunged into a
free flow of steam, the meniscus shall pass the 90° C. mark
in not more than six seconds.
The thermometer shall be inserted through a tight-fitting
cork in the neck of the flask, so that the top of the thermometer
bulb will be on a level with the bottom of the side outlet in the
neck of the flask and in the center of the neck.
METHOD OF DISTILLATION.
The flask, connected with the condenser, shall be filled with
100 cubic centimeters of the material at 15.5° C., which shall be
measured in the 100 cubic centimeter receiving cylinder. The
same cylinder may be used without drying as the receiving
vessel for the distillate. The flask shall be heated directly by a
suitable burner.
The distillation shall proceed at the rate of not less than 4
nor more than 5 cubic centimeters per minute, into the receiv-
ing cylinder. The temperature at which the first drop leaves
the lower end of the condenser shall be considered the initial
boiling-point.
Readings of the quantity in the receiver shall be taken when
the next 10° point is reached, and for every even 10° there-
after. For example, if initial boiling-point occurs at 104°,
then the first reading of the quantity in the receiver shall be
made at 110°, and thereafter at 120°, 130°, etc.
The distillation shall be continued until the point is reached
where the last drop is vaporized, when a puff of white vapor
usually appears in the bottom of the flask. The temperature at
100
10 I
102
103
|o<»
105
ioa
107
7 \
22
FIG. 40.
this point shall be considered the end or dry point of distilla-
tion.
The total yield of distillate shall not be less than 97 per cent.
184
(This method is adapted with some modification from re-
port of Sub-Committee, D— i, A. $. T. M., 1915).
b. Specific Gravity.
i.. Hydrometer: The hydrometer shall be of the form and
dimensions shown in Fig. 40. The cylinder shall be of the
form and dimensions shown in Fig. 41. A set of three with
FIG. 41.
ranges of 0.79 to 0.87, 0.86 to 0.94, and 0.93 to i.oi, will
suffice. The readings should be preferably taken at 15.5° C.
Before taking the specific gravity, the oil in the cylinder should
be thoroughly stirred. Care should be taken that the hydrom-
eter does not touch the sides or bottom of the cylinder when
the reading -is taken, and that the oil surface is free from froth
and bubbles. If the specific gravity is determined at a higher
temperature than 15.5° C., correction should be made by add-
ing o.ooi for each degree Centigrade excess of temperature.
(This correction figure is only an approximate one, and should
not be used when exact work is desired.)
' 2. Westphal Balance — Reference Method: The balance
should be set up and adjusted so that the plummet when sus-
pended to swing freely in air, exactly balances the beam. A
reading is then taken with the plummet immersed in water at
15.5° C., and if the balance is properly made and adjusted,
this should be i.oo. A second reading in oil at 15.5° C. gives
the specific gravity directly. If for any reason the water
reading is not i.oo, the balance should not be adjusted in
water, but the oil reading divided by the water reading should
be taken as the specific gravity.
c. Wash with Acid, Followed by Steam Distillation
for Valuation of Crudes.
Three hundred cubic centimeters of the material to be tested
are measured from a cylinder into a 500 cubic centimeter
Squibb type separatory funnel. About 4 cubic centimeters of
66° Baume sulphuric acid is added, and the contents of the
funnel thoroughly shaken, care being taken to avoid piling
up of pressure in the funnel, due to heat of reaction. After
settling for 15 minutes, the lower layer of acid is drawn off
and a second wash of 17 cubic centimeters of acid is applied,
and likewise removed. (The total amount of acid used is ap-
proximately equivalent to one pound per gallen of material.)
The last acid wash is followed by a treatment with 10 per cent,
caustic soda solution to alkaline reaction. This soda is al-
lowed to settle and is drawn off.
The treated benzol is run into a 500 cubic centimeter short-
neck bulb and distilled in a current of steam until no more oil
is visible in the distillate. The flask containing the treated
benzol should be kept warm enough by a burner during the
course of the distillation to prevent undue condensation of
steam. The volume of oil distillate is measured, and divided
i86
by three, gives the percentage of refined benzols in the crude
gas benzol.
(Steam distillation is necessary here to avoid possible de-
composition. A redistillation by method i-a may be made if
there is any indication of the presence of wash oil in the dis-
tillate.)
2. HOLDER OILS (DRIP OILS).
a. Bulb Distillation.
Same as i-a, with the exception that the distillation is not
continued to the drying point, but only to the point where 95
per cent, of the material is distilled off.
b. Specific Gravity.
Same as i-b. If the specific gravity is determined at a
higher temperature than 15.5° C., correction should be made
by adding 0.00088 for each degree Centigrade excess of tem-
perature.
c. Distillation with Dephlegmator.
One hundred cubic centimeters of the oil are placed in a flask
equipped with Hempel distilling tube, supplied with solid glass
beads of 4.8 to 5.5 millimeters diameter to a depth of 75 milli-
meters, and distilled, noting the cubic centimeters distillate at
170° C. and 200° C. The first fraction represents approxi-
mately crude benzol, toluol and solvent, and the 170-200° frac-
tion heavy naphtha.
NOTE. — A 6-ftulb Lebel column or 12-bulb Young pearhead
flask may be substituted for the Hempel tube in this test.
d. Naphthalene.
The residue above 200° left in the flask (c) is transferred
to a copper beaker and cooled to 15.5° C. for 15 minutes.
The mass is filtered on a perforated funnel in a suction pump
and sucked dry. The naphthalene in the filter is then pressed
between paper in a letter press to remove all oil, and weighed.
This test is not very accurate.
i87
3. BENZOLS AND REFINED NAPHTHAS.
a. Bulb Distillation.
Same as i-a, with the exception of tests on pure benzol and
pure toluol. With these materials, readings of the per cent.
distilled are taken every 0.2° C. and a thermometer of the
following specifications may be used:
Dimensions: —
Total length, mm. 370 — 400
Diameter, mm. 6.5—7.5
Bulb length, mm. (max.) 10
Bulb diameter, mm. 4-5—5-5
Scale. — Scale to start not less than 75 millimeters above
bottom of bulb, and to be from 240 to 270 millimeters long.
General. — The thermometer shall be furnished with an ex-
pansion chamber at the top and have a ring for attaching tags.
Range. — 60° to 140° C., in fifths of a degree.
Accuracy. — To be correct to one-fifth degree Centigrade.
b. Specific Gravity.
Same as i-b.
c. Sulphuric Acid Wash Test.
ACID WASHING TEST FOR BENZOL, TOLUOL, SOLVENT
NAPHTHA, ETC.
Semet-Solvay Company's Modification of The Barrett Company's
Method. Adopted by The Barrett Company on July I, 1916.
(Revised.)
The set of color standards consists of 15 bottles (French
squares, stoppered, I ounce capacity), each containing one of
the colored solutions made up as given below and the bottle
sealed.
When making a test for amount of acid washing a simi-
lar bottle is used. Seven cubic centimeters of 96 per cent. C.
P. sulphuric acid is put in first, and then approximately 21
cubic centimeters of the material to be tested is added; shake
thoroughly for 15 to 20 seconds and allow to stand for the
specified time; compare the resulting color of the acid layer
i88
with the standard set and determine which number it corre-
sponds to.
In pure benzol and pure toluol testing the benzol or toluol
layer must remain white, and the color of the acid layer after
standing 15 minutes, but not be darker than No. 4.
For 90 per cent, benzol and all grades of benzol and toluol
other than pure, the benzol and toluol layer must remain white,
and the color of the acid layer after standing 15 minutes must
not be darker than No. 6.
For xylol, the xylol layer must remain white and the color
of the acid layer after standing 15 minutes must not be darker
than No. 6.
For solvent naphtha the acid layer color only is noted, and
after 5 minutes standing it must not be darker than No. 14.
It is well to note that the above schedule shows the limit of
color allowable in the sales specifications; and it is to be ex-
pected that to consistently pass the test, works practice should
call for a limit of at least one number lighter in each case.
The solutions for the standards are made up as follows :
The following basic solutions are used:
A. 59.4965 grams CoCl2.6H2O (nickel free) is made up to
1,000 cubic centimeters with a mixture of 25 cubic
centimeters 31 per cent. HC1 and 975 cubic centi-
meters H2O.
B. 45.054 grams FeCl3.6H,2O made up to 1,000 cubic centi-
meters with a mixture of 25 cubic centimeters 31 per
cent. HC1 and 975 cubic centimeters H2O.
C. 3.5 volumes of solution A -f- 36.5 volumes solution B -)-
90 volumes of H2O.
D. 3.5 volumes of solution A + 36.5 volumes of solution B
(No water is added.)
E. Solution of K2CrO4 saturated at 21° C.
F. One volume of a solution of K2Cr2O7 saturated at 21° C.
+ i volume of H2O.
As standard color solutions to be used for comparison the
following are made up and numbered from o to 14 :
rig
No. o. — Pure water.
No. i. — i volume of solution C + i volume of H2O.
No. 2.. — 5^ volumes of solution C + 2 volumes of H2O.
No. 3. — Solution C as such.
No. 4. — i volume of solution D -|- i volume of H2O.
No. 5. — 5^2 volumes of solution D -j- 2 volumes of H2O.
No. 6. — Solution D as such.
No. 7. — 5 volumes of solution E + 2 volumes of water.
No. 8. — Solution E as such.
No. 9. — 7 volumes of solution E + J^ volume of solution
F.
No. 10. — 6^ volumes of solution E -j- i volume of solu-
tion F.
No. ii. — 5^2 volumes of solution E + 2 volumes of solu-
tion F.
No. 12. — i volume of solution E + i volume of solution F.
No. 13. — 2 volumes of solution E + 5 volumes of solution
F.
No. 14. — Solution F as such.
(These standard solutions should, in all cases, remain stop-
pered to prevent evaporation.)
To make the test place approximately 7 cubic centimeters
of C. P. sulphuric acid and 21 cubic centimeters of the light
oil to be tested in one of these standard bottles, shake thor-
oughly and stand aside for 15 minutes (in all cases excepting
the test for solvent naphtha, in which 5 minutes is the limit.)
At the end of 15 minutes compare the color produced in the
sample with that of the standard solution by looking through
the tube towards the light.
In making up the standard color comparison solutions, put
in an amount of colored solution equivalent to the amount of
acid used in the test, and on top of it put the amount of benzol
used in the test. This gives an apparent exact duplicate of a
wash test. In all cases, except solvent naphtha, the light oil
should remain white, the color test being applied only to the
color of the acid. In the case of solvent naphtha no specifica-
tion is made as to the color of the solvent naphtha itself, since
13
190
it will not be white, but the color of the acid compared with
this standard color solution determines the degree of washing.
For pure benzol and toluol, standard sample No. 4 has been
adopted as the greatest amount of color allowable for these
grades. For all commercial grades, such as 90 per cent, ben-
zol, 50 per cent, benzol and commercial toluol, No. 6 is the
lowest color limit. For solvent naphtha No. 14 has been
adopted.
d. Solidifying Point (for pure benzol only).
Fifty cubic centimeters are taken in a test tube with the
thermometer in the liquid, and cooled with stirring until sep-
aration of crystals occurs. At this point there is a constant
temperature for a considerable period, which is taken as the
solidifying point. If the material supercools, the temperature
rises as the crystals separate, and the highest point reached is
taken as the solidifying point.
e. Unnitrifiable Hydrocarbons.
Place 100 cubic centimeters of material in a flask of about
500 cubic centimeters capacity, provided with a dropping fun-
nel and a long tube (drawing) for condensing any hydrocar-
bon volatilizing. Prepare a mixture of 150 grams nitric acid
of specific gravity 1.4, and 180 or 200 grams sulphuric acid,
specific gravity 1.84, which must be allowed to cool before use.
Run this, drop by drop, through the tap- funnel into the ben-
zol, shaking this up almost constantly. As soon as the tem-
perature rises, cool the flask by immersing it in a dish full of
water. When all the acid has been added, and when no further
rise of temperature takes place spontaneously, heat the flask
gently for an hour or two (during this time the tube is best
replaced by a proper reflux condenser). Allow the whole to
settle, and separate the lower acid layer by means of a separa-
ting funnel from the crude nitrobenzol. Dilute the acid with
several times its bulk of water ; any oily liquid separating after
a few hours' rest is added to the nitrobenzol. Wash the
crude nitrobenzol three times with its own bulk of water,
191
once with a very dilute solution of caustic soda (if this so-
lution is employed too concentrated, an emulsion is formed
which is very awkward to manage), and again with water,
taking care that no oil is lost in separating the washings.
The well-settled liquor can be at once tested for its specific
gravity, which in the case of 90 per cent, benzol ought
to be 1.20; with 50 per cent, benzol 1.19 at 15°; but this
is not decisive, as the nitrobenzol is not quite free from water,
and some benzol may have escaped nitrification. The liquor
is therefore distilled from a fractionating flask till the tem-
perature has reached 150°, and the distillate is once more
nitrated, but this time with large excess of the acid mixture;
anything remaining undissolved may be regarded as unnitrifi-
able hydrocarbons. Theoretically, 100 parts of benzol furnish
157.6 of nitrobenzol; 100 parts of toluol, 148.9 of nitrotoluol.
(Taken from Lunge's Coal Tar and Ammonia.)
NOTE:— This method is not accurate with material containing small quantities
of paramne.
4. TAR.
a. Water.
Measure 50 cubic centimeters of coal tar naphtha or light
FIG. 42.
oil (which must be tested to determine that it is free from
1 92
193
water, whenever a new supply is required) in a 250 cubic
centimeter measuring cylinder. (No objection is raised to
measuring the tar direct into the still or in other ways, but
the measurement must be made as described in case of dis-
pute.) Add 200 cubic centimeters of the tar. Transfer con-
tents of cylinder to copper still and wash the cylinder with
50-75 cubic centimeters more of naphtha, adding the washings
to contents of the still. Attach lid and clamp, using a paper
gasket and set up apparatus (Fig. No. 42). Apply heat by
means of the ring burner and distil until the vapor temper-
ature, as indicated by the thermometer (in this and all other
tests care must be used to have the thermometer set exactly
as shown in drawing) has reached 205° C. The distillate is
collected in the separatory funnel, to which 15-20 cubic centi-
meters of benzol have been previously added. This effects a
clean separation of the water and oil. The reading is made
after twirling the funnel and allowing to settle for a few min-
utes. The percentage is figured by volume.
NOTE. — In case a large percentage of water is present, a
vacuum head as shown in Fig. 32, Chap. II, "Tar," may be
used to advantage.
b. Distillation.
Apparatus. — The apparatus shall consist of the following
standard parts:
(a) Flask. — The distillation flask shall be a 250 cubic centi-
meter Engler distilling flask, having the following dimensions :
Diameter of bulb, cm. 8.0
Length of neck, cm. 15.0
Diameter of neck, cm. 1.7
Surface of material to lower side of tubulature, cm n.o
Length of tubulature, cm 15.0
Diameter of tubulature, cm. 0.9
Angle of tubultaure 75°
A variation of 3 per cent, from the above measurements will
be allowed.
The thermometer shall conform to the following require-
ments :
The thermometer shall be made of resistance glass of a
quality equivalent to suitable grades of Jena or Corning makes.
194
It shall be thoroughly annealed. It shall be filled above the
mercury with inert gas which will not act chemically on or
contaminate the mercury. The pressure of the gas shall be
sufficient to prevent separation of the mercury column at all
temperatures of the scale. There shall be a reservoir above
the final graduation large enough so that the pressure will not
become excessive at the highest temperatures. The thermom-
eter shall be finished at the top with a small glass ring or
button suitable for attaching a tag. Each thermometer shall
have for identification the makers' name, a serial number, and
the letters "A. S. T. M. DISTILLATION."
The thermometer shall be graduated from o° to 400° C. at
intervals of i° C. Every fifth graduation shall be longer than
the intermediate ones, and every tenth graduation beginning at
zero shall be numbered. The graduation marks and numbers
shall be clear-cut and distinct.
The thermometer shall conform to the following dimensions :
Total length, mm 385 maximum
Diameter of stem, mm 7, tolerance 0.5
Diameter of bulb, mm 5 minimum, and shall not
exceed that of the
stem
Length of bulb, mm 12.5, tolerance 2.5
Distance o° to bottom of bulb 30, tolerance 5
Distance o°-4OO° 295, tolerance 10
The accuracy of the thermometer when delivered to the
purchaser shall be such that when tested at full immersion the
maximum error from o°-2OO° C. shall not exceed 0.5° ; 200°-
300° C., it shall not exceed i° C. ; 3OO°-375° C., it shall not
exceed 1.5° C.
The sensitiveness of the thermometer shall be such that
when taken at a temperature of 26° C. and plunged into a
free flow of steam, the meniscus shall pass the 90° C. mark
in not more than six seconds.
(c) Condenser. — The condenser tube shall have the follow-
ing dimensions:
Length of tube, mm 500
Width of tube, mm. 12 to 15
Width of adaptor end of tube, mm . 20 to 25
195
(d) Stands. — Two iron stands shall be provided, one with
a universal clamp for holding the condenser, and one with a
light grip arm with a cork-lined clamp for holding the flask.
(e) Burner and Shield. — A Bunsen burner shall be provided
with a tin shield 20 centimeters long by 9 centimeters in diam-
eter. The shield shall have a small hole for observing the
flame.
(/) Cylinders. — The cylinders used in collecting the distil-
late shall have a capacity of 25 cubic centimeters and shall be
graduated in tenths of a cubic centimeter.
Setting up the Apparatus. — The apparatus shall be set up as
Fig. 44.— Apparatus for the distillation of tar.
196
shown in Fig. 44, the thermometer being placed so that the
top of the bulb is opposite the middle of the tubulature. All
connections should be tight.
Method. — One hundred cubic centimeters of the dehydrated
material to be tested shall be placed in a tared flask and
weighed. After adjusting the thermometer, shield, condenser,
etc., the distillation is commenced, the rate being so regulated
that I cubic centimeter passes over every minute. The re-
ceiver is changed as the mercury column passes the fraction-
ating point.
The following fractions should be reported :
Start of distillation to no°C.
iro°C. to iyo°C.
iyo°C. to 235°C.
235°C. to 2yo°C.
27o°C. to 3i5°C.
3i5°C. to 355°C.
Residue
To determine the amount of residue, the flask is weighed
again when distillation is complete. During the distillation the
condenser tube shall be warmed when necessary to prevent
the deposition of any sublimate. The percentages of fractions
should be reported both by weight and by volume.
(This method is adapted with some modification from re-
port of Subcommittee on Distillation, Committee D-4, A. S.
T. M., 1911.)
c. Specific Gravity.
1. Hydrometer. — Same as i-b. A set of three with ranges
of 1.07 to 1.15, 1.14 to 1.22, and 1.21 to 1.30 will suffice. The
hydrometer can only be used on tars for rough work, and is
used at any convenient temperature. If the specific gravity is
determined at a higher temperature than 15.5° C., correction
should be made by adding 0.000685 for each degree Centigrade
excess of temperature.
2. Modified Hubbard Bottle. — For accurate work with the
bottle^ the test should be made on dry tar only. The type of
197 .
bottle used is shown in Fig. 45. The following weights are
noted :
a. Weight of empty bottle.
b. Weight of bottle filled with water to the mark of
15.5° c.
c. Weight of bottle partly filled with tar.
d. Weight of bottle with tar and water adjusted to the
mark at 15.5° C.
c — a
The specific gravity then is 7-7— , .
(^ 0 d) \u — C)
FIG. 45.
. — Freshly distilled water should be used in this work.
d. Free Carbon.
APPARATUS.
Extractor. — The extraction apparatus is shown in Fig. 46.
FIG. 46.
198
Filter Cups. — The filter cups or thimbles are made of
Schleicher and Schull No. 575 hardened filter paper, which
comes in cut circles. The size used is 15 centimeters in diam-
eter. To make a cup, two circles should be taken and one cut
down to a diameter of about 14 centimeters. A round stick
about i inch in diameter is used as a form. The stick is placed
in the center of the circles of filter paper, the smaller inside;
the papers are then folded symmetrically around the stick to
form a cup of about 2j/2 inches in length. A very little prac-
tice enables the operator to make these evenly and quickly.
After being made, they are soaked in benzol to remove any
grease due to handling, drained, dried in a steam oven and
kept in a desiccator until used.
Method. — If tar is to be assayed, it must be dried before
testing, and after drying it is passed hot through a 3O-mesh
sieve to remove foreign substances.
For materials of 5 per cent, or more carbon content, 5 grams
should be taken for the test. With lesser percentages, 10
grams should be used. The amount is weighed out in a 100
cubic centimeter beaker, and digested with about 50 cubic cen-
timeters of chemically pure toluol on the steam bath for a
period not to exceed 30 minutes. If the solution is kept hot
and constantly stirred, the digestion can be completed very
rapidly. A filter cup, prepared as described, is weighed in a
weighing bottle and placed in a carbon filter tube over a beaker
or flask. The toluol-tar mixture is now decanted through the
thimble and washed with hot chemically pure toluol until
clean, using some form of policeman which is unaffected by
toluol for the purpose of detaching any carbon which may ad-
here to the beaker. The cup is finally given a washing with
hot chemically pure benzol and then, after draining is cov-
ered with a cap of filter paper or alundum, and placed in the
extracting apparatus in which chemically pure benzol is used
as a solvent. The extraction is continued until the descend-
ing benzol is colorless. The thimble is then removed, the cap
taken off, dried in the steam oven, and weighed in the weighing
bottle after cooling in the desiccator. The balance used for
199
this work should be accurate to at least a half milligram.
NOTE). — If desired, carbon bisulphide may be used instead of
benzol and toluol as a solvent, but the results may not be com-
parable.
5. TAR L,IGHT OILS.
a. Bulb Distillation.
Same as 2-a.
b. Tar Acids.
The distillate from (a) is placed in a separatory funnel
(Fig. 47). If the light oil is not liquid at room temperature,
FIG. 47.
it should be kept in a constant temperature bath at a point
high enough to insure all solid matter remaining in solution.
After the material in the funnel has come to constant tem-
perature, the reading is noted and 50 cubic centimeters of a
10 per cent, caustic soda solution added. It is then shaken and
allowed to settle, the soda drawn off, the oil allowed to come
to its original temperature, and the shrinkage noted. This
process is repeated with successive portions of 30 cubic centi-
meters each of the same soda solution, until no further shrink-
age is noted. The total shrinkage is taken as the percentage
of tar acids.
(This test is empirical, and it would be desirable to have a
more accurate method).
c. Distillation with Dephlegmator.
Same as 2-c. In this case the extracted oil from the tar acid
determination is used instead of the original.
d. Naphthalene.
Same as 2-d. Made on residue above 200° from 5-^.
e. Specific Gravity.
Same as i-b. A set of two hydrometers with ranges of
200
0.86 to 0.94, and 0.93 to i.oi, will suffice. If the specific grav-
ity is determined at a higher temperature than 15.5° C., cor-
rection should be made by adding 0.0009 f°r eacn degree
Centigrade excess of temperature.
Reference method, same as i-b (2).
6. TAR MIDDLE OILS.
a. Bulb Distillation.
Same as 2-a.
b. Specific Gravity.
Same as i-b. A set of two hydrometers with ranges of 0.93
to i.oi, and i.oo to 1.08 will suffice. If the specific gravity is
determined at a higher temperature than 15.5° C., correction
should be made by adding 0.00085 for each degree Centigrade
excess of temperature.
Reference method, same as i-b (2).
c. Tar Acids.
Same as 5-^.
d. Naphthalene.
Same as 2-d.
7. TAR HEAVY OILS (CREOSOTE OILS).
a. Distillation.
Retort. — This shall be a tubulated Jena glass retort of the
usual form with a capacity of 250 to 290 cubic centimeters.
FIG. 48.
The capacity shall be measured by placing the retort with the
201
bottom of the bulb and the end of the offtake in the same
horizontal plane, and pouring water into the bulb through the
tubulature until it overflows the offtake. The amount remain-
ing in the bulb shall be considered its capacity. (See Fig. 48.)
Condenser Tube. — Any suitable form of glass tubing may be
used. (Fig. 49.)
FIG. 49.
Shield. — To be made of asbestos (Fig. 50) shall be used to
protect the retort from air currents and to prevent radiation.
This may be covered with galvanized iron, as such an arrange-
ment is more convenient and more permanent.
-1
FIG. 50,
Receivers. — Erlenmeyer flasks of 50 to 100 cubic centi-
meters capacity are most convenient forms.
The thermometer shall conform to the following require-
ments :
The thermometer shall be made of resistance glass of a
quality equivalent to suitable grades of Jena or Corning makes.
2O2
It shall be thoroughly annealed. It shall be filled above the
mercury with inert gas which will not act chemically on or
contaminate the mercury. The pressure of the gas shall be
sufficient to prevent separation of the mercury column at all
temperatures of the scale. There shall be a reservoir above
the final graduation large enough so that the pressure will not
become excessive at the highest temperatures. The thermom-
eter shall be finished at the top with a small glass ring or
button suitable for attaching a tag. Each thermometer shall
have for identification the makers' name, a serial number, and
the letters "A. S. T. M. DISTILLATION."
FIG. 51.
The thermometer shall be graduated from o° to 400° C. at
intervals of i° C. Every fifth graduation shall be longer than
the intermediate ones, and every tenth graduation beginning at
zero shall be numbered. The graduation marks and numbers
shall be clear-cut and distinct.
The thermometer shall conform to the following dimensions :
Total length, mm 385 maximum
Diameter of stem, mm 7, tolerance 0.5
Diameter of bulb, mm 5 minimum, and shall not
exceed that of the
stem
Length of bulb, mm 12.5, tolerance 2.5
Distance o° to bottom of bulb. . . . 30, tolerance 5
Distance o°-4OO° 295, tolerance 10
203
The accuracy of the thermometer when delivered to the
purchaser shall be such that when tested at full immersion the
maximum error from o°-2OO° C. shall not exceed 0.5° ; 200°-
300° C., it shall not exceed i° C. ; 3OO°-375° C., it shall not
exceed 1.5° C.
The sensitiveness of the thermometer shall be such that
when taken at a temperature of 26° C. and plunged into a
free flow of steam, the meniscus shall pass the 90° C. mark
in not more than six seconds.
FIG. 52.
Assembling. — The retort shall be supported on a tripod of
rings over two sheets of 2o-mesh gauze 6 inches square. It
shall be connected to the condenser tube by a tight cork joint.
The thermometer shall be inserted through a cork in the tubu-
lature with the bottom of the bulb y2 inch from the surface of
the oil in the retort. The exact location of the thermometer
bulb shall be determined by placing a vertical rule graduated
in division not exceeding 1/16 inch back of the retort when
the latter is in position for the test, and sighting the level of
2O4
the liquid and the point for the bottom of the thermometer
bulb. The distance from the bulb of the thermometer to the
outlet end of the condenser tube shall be not more than 24
nor more than 20 inches. The burner should be protected
from draughts by a suitable shield or chimney.
Method. — Exactly 100 grams of oil shall be weighed into
the retort, the apparatus assembled and heat applied. The dis-
tillation shall be conducted at the rate of at least one drop and
not more than two drops per second, and the distillate col-
lected in weighed receivers. The condenser tube shall be
warmed whenever necessary to prevent accumulation of solid
distillates. Fractions shall be collected at the following points :
Up to i7o°C.
I7O tO 2OO°C.
200 tO 2IO°C.
210 tO 235°C.
235 to 27o°C.
270 to 3i5°C.
315 to 355°C.
The receivers shall be changed as the mercury passes the
dividing temperature for each fraction. The last receiver shall
be removed at 355° C., and the drainage from the condenser,
etc., shall not be considered as a part of the fraction. For
weighing the receivers and fractions, a balance accurate to at
least 0.05 gram shall be used. During the process of distilla-
tion the thermometer shall remain in its original position. No
correction shall be made for the emergent stem of the ther-
mometer.
When any measurable amount of water is present in the
distillate, it shall be separated as nearly as possible and re-
ported separately, all results being calculated on a basis of
dry oil. When more than 2 per cent, of water is present,
water-free oil shall be obtained by separately distilling a larger
quantity of oil, returning to the oil any oil carried over within
the water, and using dried oil for the final distillation. A
205
copper tar still is a convenient means of obtaining water-free
oil.
(This method is adapted with some modification from report
of Sub-Committee on Preservatives, Committee D-7, A. S.
T. M., 1915.)
Other methods for the distillation of creosote oil have been
described by the National Electric Light Association, the For-
est Service, and Lunge (Coal Tar and Ammonia).
b. Specific Gravity.
1. Same as i-b. A set of two hydrometers with ranges of
i.oo to i. 08 and 1.07 to 1.15 will suffice. If the specific grav-
ity is determined at a higher temperature than 15.5° C., cor-
rection should be made by adding 0.0008 for each degree Cen-
tigrade excess of temperature.
2. Westphal Balance — Reference Method. See i-b (2). A
reading is taken with the plummet immersed in water at 38°
C., and a second reading in oil at 38° C. The specific gravity
is the oil reading divided by the water reading, times 0.9939
(the density of water at 38° C. divided by the density at 15.5°
C.).
c. Tar Acids.
Same as 5-^. As most creosote oils are not liquid at ordi-
nary temperatures, it is customary to determine the tar acids
at a constant temperature of 60° C.
8. PITCH.
a. Distillation.
Same as 4~b.
b. Specific Gravity.
Apparatus. — This consists entirely of a platinum pan having
a total weight of about 7 grams.
Method. — The pan is suspended above the balance pan by a
fine, waxed silk thread, and the weight in air and water at
15.5° C. determined. It is then filled with pitch and weighed
both in air and in water at 15.5° C.
2O6
Formula. — Let a = weight of pan in air.
b = weight of pan in water.
c = weight of pan plus pitch in air.
d =: weight of pan plus pitch in water.
The specific gravity == (f? ~^ ^
a. Modified Hubbard Bottle. — Same as 4-0.
c. Free Carbon.
Same as 4~d. In case the pitch is hard enough, it should be
ground before making the test, and the residue in the extrac-
tion thimble should be examined for extraneous matter, such
as sticks of wood or pieces of bagging.
d. Melting Point.
Apparatus shown in Fig. 53.
1. Pitches having melting-points from 43° to 77° C.
Pitches of this consistency can ordinarily be molded at room
temperature, or if necessary, cold or hot water can be used to
harden or soften them. The molds should always be scrupu-
lously clean, but may be moistened if necessary.
A clean-shaped J/2-inch cube of the pitch to be formed in
the mold, placed on the hook of No. 12 B. & S. gauge copper
wire (diameter 0.0808 inch), and suspended in the 600 cubic
centimeter beaker, so that the bottom of the pitch is I inch
above the bottom of the beaker. (A sheet of paper placed on
the bottom of the beaker and conveniently weighted will pre-
vent pitch from sticking to the beaker when it drops off.)
The pitch is to remain five minutes in 400 cubic centimeters of
freshly boiled distilled water at a temperature of 15.5° C. be-
fore heat is applied; heat to be applied in such a manner
that the temperature of the water is raised 5° C. each min-
utes ; the temperature recorded by the thermometer at the
instant the pitch touches the bottom of beaker to be considered
the melting-point.
2. Pitches having melting-points below 43° C.
207
Same method as described in (i), except that at the start
the water should have a temperature of 4° C. The cubes can
be conveniently formed in water at the temperature specified.
3. Pitches have melting-points above 77° C.
Pf/-cfy
FIG. 53.
It is usually necessary to heat these pitches in order to form
the cube. For this purpose a copper cup of approximately 50
cubic centimeters capacity, i'J/£ inches deep and il/2 inches
diameter, provided with wooden handle, can be used. The
cup should be half-filled with pitch and heated carefully, avoid-
ing noticeable evolution of vapors, and the heating should not
208
be continued any longer than absolutely necessary. An oil
bath may be used for this purpose.
FIG. 54.
For these pitches an air bath is substituted for the water
bath. The hook is shorter, so that the cube is suspended on a
2OQ
line running through the center of the observation windows,
the thermometer bulb being at the same level. The tempera-
FIG. 55.
ture of the oven is raised 5° C. each minute, as usual, and the
temperature recorded by the thermometer at the instant the
pitch drops to the bottom of the oven, is considered the melt-
2IO
ing-point. To make results by this method comparable with
results obtained in water, 6.5° C. should be added to the ob-
served melting-point. (Important. — Results by this method
are not directly comparable with results obtained in water, but
are always lower.)
FIG. 56.
NOTE:. — Melting-point apparatus should be set up in a place
free from drafts, and if necessary, protected by means of a
shield set apart from the apparatus.
Same as 4~b.
Same as S-b.
Same as 4~d.
9. ROAD TARS.
a. Distillation.
b. Specific Gravity.
c. Free Carbon.
d. Viscosity.
Taken in the Engler viscosimeter at the temperature re-
quired by specifications. The full quantity, 250 cubic centi-
meters, is placed in the apparatus and raised to the tempera-
ture at which it is desired to make the test. One hundred cubic
centimeters are then permitted to flow into a graduated flask
of the above capacity, and the time of flow in seconds noted.
211
e. Float Test.
Apparatus. — Consists of two parts, an aluminum float or
saucer, and a conical brass collar. (Fig. 57.)
FIG. 57.
Method. — The brass collar is placed upon a brass plate, the
surface of which has been amalgamated, and filled with the bitu-
minous material under examination, after it has been softened
sufficiently to flow freely by gentle heating. The collar must
be level-full, and as soon as the bitumen has cooled sufficiently
to handle, it is placed in ice water at 4° C. for 15 minutes. It
is then attached to a float and immediately placed upon the
surface of the water, which is maintained at the desired tem-
perature.
As the plug of bitumen in the brass collar becomes warm
and fluid, it is gradually forced out of the collar, and as soon
as the water gains entrance to the saucer the entire apparatus
sinks below the surface of same.
The time elapsing between placing the apparatus on the
water and when the water breaks through the bituminous
material is noted by means of a stop watch.
10. NAPHTHALENE SALTS (CRUDE NAPHTHALENE).
a. Water.
\Yeigh 200 grams into a copper still, add 100 cubic centi-
meters of water-free naphtha and distil up to 210° C. vapor
temperature. Note volume of water as in similar test on tar.
b. Solidifying Point.
If water is present it must be removed by proper distillation,.
212
as in creosote oil. About 20 cubic centimeters of melted
naphthalene are taken in a test-tube of thin glass about I inch
in diameter by 6 inches long. The contents are thoroughly
liquified and then allowed to cool, stirring constantly with an
accurate thermometer. As permanent crystals begin to form,
a constant temperature is held for a short time; this is taken
as the solidifying point. Often, if the material supercools,
the temperature rises as the solids separate; in this case the
highest point attained on the rise is recorded. The higher
the solidifying point is, the longer the period of constant tem-
perature, and hence the sharper the test.
c. Distillation.
Weigh 100 grams of dried naphthalene into a regular 200
cubic centimeter side-neck distilling bulb. Connect to a 24-
inch condenser tube (from the water-in-tar-testing apparatus).
Water cooling should not be used. Use a standard creosote
oil distillation test thermometer and collect the distillate in a
100 cubic centimeter graduated cylinder. Conduct the test as
in the regular bulb distillation of naphthas or light oils, noting
the first drop, the cubic centimeters distilled every 10° C.
up to 210° C. ; then every 5° C. to 230° C. and every 10° C.
up to the decomposition point. This is indicated by the ap-
pearance of white fumes in the flask. During the course of
the test, the condenser tube should be kept warm enough to
keep the distillate liquid by playing a flame over it.
CHAPTER V.
MISCELLANEOUS.
WATER ANALYSIS.
Sampling.
A sample of water should not be taken except when the
supply is being drawn on at the normal operating rate. All
taps or connections through which the sample passes must be
thoroughly flushed out. The vessel to contain the sample
should be cleaned with care and then thoroughly rinsed sev-
eral times with the water to be sampled. Metal containers
and earthenware jugs may contaminate the sample. A i-
gallon bottle with a ground glass stopper is the best container
for samples of water.
Total Solids. — Evaporate 250 cubic centimeters to dryness
in a platinum dish (weighed), dry in an air oven at 100° C.
Cool and weigh.
Organic and Volatile Matter. — Ignite the contents of the
dish at a low red heat. Cool and weigh. The loss will be
organic and volatile matter.
Mineral Solids. — Subtract the weight of the dish from the
weight just found above. The difference will be the weight
of the mineral solids. The results found above in milligrams
multiplied by 4 will be the parts per million.
Alkalinity or Temporary Hardness. — Measure 100 cubic
centimeters of the water into a 250 cubic centimeter glass-
stoppered bottle, add 2.5 cubic centimeters Erythrosine solu-
tion (o.i gram of the sodium salt in i liter distilled water),
and 5 cubic centimeters chloroform. Add N/5O H2SO4 in
small quantities, shaking vigorously at each addition. The
rose color gradually disappears, and is finally entirely dis-
charged by a drop or two of the acid. A white paper held
behind the bottle facilitates the detection of any color remain-
ing as the end-point is reached. The number of cubic centi-
meters of the acid used multiplied by 10 gives the number of
parts per million alkalinity in terms of CaCO3.
214
Incrustants or Permanent Hardness. — Measure 200 cubic
centimeters of the water into a Jena glass Erlenmeyer flask,
boil 10 minutes to expel free CO2. Add 25 cubic centimeters
of N/io soda reagent (equal parts of N/io NaOH and N/io
Na2CO3), and boil to a volume of 100 cubic centimeters.
Cool and rinse into a 200 cubic centimeter graduated flask,
make up to the mark with boiled distilled water. Filter, and
reject the first 50 cubic centimeters. Titrate 100 cubic centi-
meters of the remainder for excess of soda reagent with N/2O
HaSG4, using Erythrosine as an indicator as above. If S
equals the cubic centimeters of N/2O H2SO4 equivalent to the
soda reagent used, and N equals the cubic centimeters of N/2O
H2SO4 required for the excess or back titration, then the in-
crustants in parts per million CaCO3 will be: 12.5 (S — 2N).
Total hardness is the sum of the alkalinity and incrustants.
Mineral Analysis.* NOTE. — The volume taken for analysis
depends on the quantity of total solids present in the water.
The calculations of the following method are based on a vol-
ume of i liter of water.
Method. — Evaporate I liter in a platinum dish to about 5
cubic centimeters. Filter into a 200 cubic centimeter gradu-
ated flask. Wash with successive small quantities of hot dis-
tilled water by putting the water into the dish, rinsing it
around and pouring it on the filter.
The solution in the flask contains probably Cl, SO3, Mg,
alkalies, and Ca.
The residue in the dish and on the filter contains probably
Si02, A1203, Fe203, CaCO3, and MgCOa.
Treatment of the Solution. — Cool the flask and fill to the
mark with distilled water. Mix well and divide into three
parts.
Part a. — Fifty cubic centimeters equivalent to 250 cubic cen-
timeters original water. Determine Cl with standard AgNO3.
Milligrams Cl multiplied by 4 gives parts Cl per million.
Part b. — Fifty cubic centimeters equivalent to 250 cubic
centimeters original water. Slightly acidify with HC1 and
determine SO3 by precipitating with BaSO4. BaSO4 multi-
215
plied by 0.343 equals SO3. Milligrams SO3 multiplied by 4
gives parts SO3 per million.
Part c. — One hundred cubic centimeters equivalent to 500
cubic centimeters original water. Slightly acidify with HC1.
Make faintly alkaline with NH4OH, boil, and add ammonium
oxalate, allow to stand over night, filter, wash, ignite, and weigh
the CaO. CaO multiplied by 0.715 equals Ca. Milligrams Ca
multiplied by 2 equals parts Ca per million. Evaporate the fil-
trate to dryness in a weighed platinum dish, add a few drops of
H2SO4 and ignite until white fumes are all driven off. Cool
and weigh as MgSO4 + Na2SO4. Dissolve in warm water,
filter if necessary, acidify slightly with HC1. Place beaker
in a dish cooled with ice, add 5 cubic centimeters sodium phos-
phate, then make strongly alkaline with ammonia. Stir for
about 3 minutes and set aside over night. Filter, and wash
with water containing 10 per cent. NH4OH and 10 per cent.
NH4NO3. Dry in an oven. Ignite in a porcelain crucible.
Weigh as Mg2P2O7. Mg2PaO7 multiplied by 0.362 gives MgO.
Milligrams MgO multiplied by 2 gives parts MgO per million.
Mg2PeO7 multiplied by 1.0814 gives MgSO4, which deducted
from the contents of the dish found above gives Na2SO4.
Na2SO4 multiplied by 0.324 gives Na2. Milligrams Na2 mul-
tiplied by 2 gives parts Na per million in the water.
NOTE;. — The chlorine found may be checked in two ways :
1. By dissolving the contents of the dish in mineral solids
in H2O, and titrating with standard AgNO3.
2. By taking 100 cubic centimeters of the original water,
boiling out the Col2, cooling and titrating with standard
AgN03.
Calculations from above :
Calculate Na to NaCl.
Cl remaining to MgCl2.
Cl remaining to CaCl2.
Mg remaining to MgSO4.
SO3 remaining to Na2SO4.
Residue in Dish and on Filter Paper. — Place filter and con-
tents in the dish, dry over a Bunsen burner flame, care-
2l6
fully burn paper, and ignite to burn off carbon. Add a little
HC1 and rinse around the dish. Evaporate to dryness, redis-
solve in a little acid, and evaporate again to dryness. Take
up again with a little acid, add water, boil and filter into a
200 cubic centimeter graduated flask. Wash thoroughly.
Dry, ignite, and weigh the filter in a platinum crucible; this
gives SiO2; milligrams of which equals parts per million in
the original water. Cool the flask and contents, fill to the
mark with distilled water and mix well. Divide this solution
into two parts.
Part a. — Fifty cubic centimeters equivalent to 250 cubic
centimeters of original water. Determine SO3 as BaSO4, as
before described. BaSO4 multiplied by 0.343 equals SO3.
Milligrams SO3 multiplied by 4 equals parts per million in
original water.
Part b. — One hundred fifty cubic centimeters equivalent to
750 cubic centimeters original water. Add a few drops
of HNO3 and boil. Make faintly alkaline with ammonia and
boil until odor of ammonia has gone. Filter off Al and Fe
hydroxides, wash, dry, ignite and weigh as A12O3 -j- Fe2O3.
Milligrams of AleO3 divided by Fe2O3 multiplied by 4/3 equal
parts per million in the original water.
Filtrate. — Boil, add ammonium oxalate, and allow to stand
for 4 hours, filter, wash with hot water, dry, ignite in a plati-
num crucible, finishing over a blast lamp to constant weight.
Milligrams CaO multiplied by 4/3 equal parts CaO per mil-
lion in the original water.
Filtrate. — Concentrate to about 50 cubic centimeters adding
HNO3 to destroy the NH4C1 if necessary, precipitate Mg2P2O7
as usual. Mg2P2O7 multiplied by 0.362 gives MgO, milligrams
of which multiplied by 4/3 equal parts per million in the
original water.
Calculations from above :
Calculate SO3 to CaSO4.
Calculate CaO remaining to CaCO3.
Calculate MgO to MgCO3.
PAINTS.
Analysis of Red Holder Paint.
Weigh out 0.5 gram of the dry pigment after extraction of
the vehicle in a porcelain casserole and add 50 cubic centi-
meters HC1 (i : i). Boil gently for 15 minutes, evaporate to
dryness on the sand bath, moisten with concentrated HC1, and
evaporate again. Moisten again with concentrated HC1, add
100 cubic centimeters of water and boil gently for a few min-
utes. Filter, wash, ignite and weigh as silica, SiO2, etc. Add
a few drops of H2SO4 to the residue and a little HC1, and
evaporate gently on a sand bath under the hood. The loss in
weight represents SiO2 ; any residue remaining should be fused
with potassium bisulphate and dissolved in HC1 and filtered.
Any residue remaining on the filter is BaSO4, which is ignited
and weighed. The filtrate is added to the filtrate from the
silica. This procedure is only necessary in case of a large
per cent, of insoluble. Otherwise, report as insoluble matter.
The combined filtrates are made up to 250 cubic centimeters
and an aliquot portion taken, made alkaline with NH4OH,
boiled, filtered, washed, ignited, and weighed as Fe2O3 and
A12O3. Take another portion and precipitate with ammonia
as before. Filter and wash, and dissolve the precipitate on
the paper with 10 per cent. H^SC^ into a flask. Add a few
pieces of zinc, stopper flask with a stopper fitted with a Bun-
sen valve and allow to stand until all the iron is reduced.
Then filter off the zinc and add 10 cubic centimeters H2SO4,
and titrate with N/io KMnO4, calculating to Fe,2O3. The
difference between these gives A12O3. The filtrate from the
iron and alumina is heated to boiling, ammonium oxalate
added, set aside on the sand bath over night, filtered, ignited
and weighed as CaO. If any magnesium is present, pre-
cipitate with sodium hydrogen phosphate in the filtrate from
the calcium as usual. Determine SO3 water of hydration, and
CO2 as usual in separate samples.
Method of Analysis of Green Pigments.
Weigh out i gram into a 200 cubic centimeter Jena beaker
2l8
and ignite gently to decompose the Prussian blue. Cool the
beaker, add 25 cubic centimeters ( I : I ) HC1, boil to dissolve
the iron oxide and expel the excess of acid. Dilute with
water and filter off the insoluble matter.
Insoluble Part. — Ignite in a platinum crucible and weigh.
Add fusing mixture and fuse to decompose the clay and bari-
um sulphate. Extract the fusion with water, dissolve the in-
soluble residue in HC1 and determine the barium as sulphate
in the acid solution.
Soluble Part. — Nearly neutralize the acid with ammonia
and precipitate the lead as sulphide with H2S. Filter off the
precipitate, dissolve in HNO3, and determine the lead as sul-
phate or chromate. Boil the filtrate to expel H2S and pre-
cipitate the iron, aluminum and chromium with ammonia.
Filter off the precipitate and in the solution determine the cal-
cium as usual. Dissolve the combined hydrates in HC1 and
dilute the solution to 100 cubic centimeters with water. Take
50 cubic centimeters and reprecipitate the metals with am-
monia. Filter, ignite and weigh as oxides. Oxidize the chro-
mium in the second 50 cubic centimeter portion by a careful
addition of Na2O2. Boil the solution to decompose the ex-
cess of peroxide, dilute with water and filter off the ferric
hydrate. The filtrate will contain the chromium as chromate
and aluminum as aluminate of sodium.
Dissolve the ferric hydrate in acid, reduce with zinc and
titrate with N/io KMnO4. Acidify the chromium solution
with H2SO4, add excess of ferrous sulphate and titrate the
unoxidized iron with KMnO4 N/io. From the amount of
FeSO4 used up to reduce the chromate, calculate the per cent,
of chromium. Calculate the iron and chromium to oxides and
subtract from the weight of the combined oxides. The alu-
mina is found by difference. Calculate the iron to Prussian
blue, and chromium to lead chromate. Determine the soluble
SO3 and water of hydration in separate samples.
219
PAINT VEHICLES.
Method of Analysis of a Mixture Consisting of Benzene, Tur-
pentine, Fatty Oils, Rosin Oil, and Petroleum.
1. Distil off and collect the benzene and turpentine, using
either a current of CO2, Note A, or of steam, Note B. Sep-
arate them by fractional distillation, Note C, by the action of
HNO3, Note D, or of H2SO4, Note E.
2. Saponify the fatty oils in the residue, Note F, with caus-
tic KOH in the usual manner. Dissolve the saponified mat-
ter in water, Note G, and the unsaponified oils in ether. Sep-
arate carefully, washing the aqueous solution with ether, and
the ethereal solution with water.
3. Evaporate off the ether and weigh the rosin oil and
petroleum oil. Treat with HNO3, Note H, extract the resid-
ual petroleum oil with ether, evaporate the latter and weigh.
Rosins, if present, would be saponified with the fatty oils,
and might be estimated in the soap solution by Cladding's
method. Tar oil would probably accompany the rosin oil in
the above scheme.
NOTE A. — Turpentine can be distilled according to H. J.
Phillips, Chem. News, 63, 275, and Jour. Chem. Ind. 10, 577,
at about 220° using about 150 grams of the sample and passing
through it a current of CO2 to prevent oxidation of the lin-
seed oil. The temperature required by this method is higher
than that used in steam distillation, and in most cases the
latter would probably be preferable.
NOTE B. — In the steam distillation, use about 25 grams of
the sample in a 400 cubic centimeter flask with a few pieces
of glass or metal to prevent bumping. Maintain at a tempera-
ture of about 110° and when the turpentine is all removed,
continue the heating long enough to remove the last portions
of water. The weight of the residue may then be taken to
check the results. The distillate is allowed to stand, the tur-
pentine and benzene are separated from the water and
weighed, and to the result is added o.ioo gram of turpentine
for every 30 cubic centimeters of water in the distillate. Ac-
220
cording to Mcllhiney, Jour. Am. Chem. Soc., 16, 348, this
method gives very accurate results.
NOTE C. — In case of a mixture of turpentine with light ben-
zene, a rough separation may be effected by fractional distilla-
tion, since the turpentine distils mainly between 150° to 180°.
A method which is not affected by the boiling-point of ben-
zene is that of separation by means of acids.
NOTE D. — The HNO3 method for separating benzene and
turpentine, due to Burton, Am. Chem. Jour., 12, 102, is thus
described by Phillips, Eng. Chem., p. 273 : A balloon flask of
750 cubic centimeters capacity is fitted with a two-hole cork
stopper. Connect with a dropping funnel and an inverted
condenser. About 300 cubic centimeters fuming HNO3 of 1.4
specific gravity are placed in the flask and 100 cubic centi-
meters of the turpentine to be tested are measured into the
dropping funnel. The flask is surrounded by cold water and
the turpentine allowed to drop slowly into the HNO3. As
each drop strikes the acid, a violent action takes place with
the evolution of red fumes. Shake occasionally, and when all
the turpentine has been added, allow to stand until all action
is over. Transfer to a separatory funnel and wash with hot
water. Finally separate and measure and weigh the benzene.
NOTE E. — Armstrong's method for the separation of ben-
zene from turpentine, Jour. Soc. Chem. Ind., I, 480, depends
upon the polmerization of the latter by H2SO4. This method
is given by Allen, Com. Org. Andy., n, 441, but it is more
time consuming than the HNO3 process and probably no more
accurate.
NOTE F. — This residue may be dried and weighed. If it
shows signs of alteration as a result of the steam distillation,
another portion may be freed from turpentine by exhaustion
of the air and gentle heating. In this case, it is necessary
after removing most of the turpentine, to add a little petro-
leum ether of very low boiling-point. This, in distilling, car-
ries the last of the turpentine with it. A residue prepared in
this way may be found in better condition for further ex-
amination than one obtained by steam distillation.
221
NOTE; G. — If the amount of fatty oil is not found by differ-
ence, it can be estimated by separating the fatty acids, weigh-
ing and them, and estimating the corresponding weight of gly-
cerides. If resin is present, the resin acids are determined by
Cladding's method. If the fatty oils present are not more
than two in number, an approximate estimate of the amount
of each may be deducted from the determination of such con-
stants as Hubl, Koettsdorfer, and acetyl figures on the sepa-
rated fatty acids.
NOTE H. — According to Mcllhiney, Jour. Am. Chem. Soc.,
*6, 385, the following process gives fairly accurate results :
Fifty cubic centimeters HNO3 of 1.2 specific gravity are
heated to boiling in a flask of 700 cubic centimeters capacity.
The source of heat is removed and 5 grams of the oil to be
analyzed added. The flask is then heated on the water bath
with frequent shaking for 15 to 20 minutes, and about 400
cubic centimeters of cold water added. After the liquid has
become entirely cold, 50 cubic centimeters of petroleum ether
are added and the flask agitated. The petroleum oil is un-
changed and dissolves in the ether. This solution is poured
into a separatory funnel, leaving the lumps of solid resin as
far as possible in the flask. After settling, the aqueous liquid
is drawn off and the ethereal layer poured into a tared flask.
The resin is washed with another portion of petroleum ether,
which is added to the first. The ether is then evaporated and
the oil weighed. Since mineral oils lose about 10 per cent, in
this wray, the weight of oil found must be divided by 0.9 to
obtain the correct value.
FIRE CLAY AND REFRACTORIES.
Chemical Analysis.
Since the heat resistance as well as the strength of refrac-
tories depends largely on its chemical composition, an analysis
can in most cases help to distinguish between good, mediocre
or bad refractories. It will also help to ascertain the cause of
failures.
15
222
Aside from physical tests it is of utmost importance to as-
certain the chemical composition of refractories. The follow-
ing elements or rather their oxides, etc., are to be considered
silica, alumina, ferrous and ferric oxides, calcium, magnesium,
alkalies, also in clay, manganese oxide, sulphur trioxide, car-
bon dioxide, silica. Dissolving in acids is in most cases im-
possible. It is therefore advisable to fuse in a platinum cruci-
ble I gram of the very finely powdered sample and 5 grams
of a fusing mixture (sodium carbonate 4 parts, potassium ni-
trate i part). The fusion is complete as soon as the evolu-
tion of the gas ceases. The crucible is next transferred to a
porcelain casserole and the fusion dissolved in hot water to
which a few drops of hydrochloric acid are added from time
to time. After the fusion has been dissolved, remove plati-
num crucible carefully, washing inside and outside well into
the casserole. Care must be taken that the content of the
casserole is acid. Evaporate to dryness, bake for a short
time at about 120° C. until all the HC1 has been driven off.
Wash the precipitate on the filter paper about 3 to 5 times
with hot dilute HC1 and then with hot water until no more
precipitate is formed by adding a drop of silver nitrate to
the filtrate collected in a test-tube, after removing beaker con-
taining the bulk of filtrate. Dry both filter papers in a tared
platinum crucible, burn and weigh the SiO2. The silica
should be perfectly white. If there is any indication of color
due to impurities it is best to add a few drops of sulphuric
acid to the silica and then add drop by drop hydrofluoric acid
until no more reaction takes place. Add^a slight excess and
evaporate to dryness, heat over a Bunsen burner, cool and
weigh. Deduct this weight from the weight of crucible and
precipitate. This gives the correct weight of SiO2. The
residue in the platinum crucible generally consists of iron
oxide. It is dissolved in HC1 and added to the bulk of fil-
trate from SiO2. The filtrate is next transferred to a 500
cubic centimeter graduated flask and made up to 500 cubic
centimeters and well stirred. One hundred cubic centimeters
of the solution are transferred to a beaker, about 10 cubic
223
centimeters of sulphuric acid added, and the whole evaporated
until all the HC1 has been driven off. It is next diluted with
water and reduced with zinc. (The most satisfactory method
is a Jones reducteur, but stick zinc will do where a Jones
reducteur is not available) and titrated with a standard solu-
tion of potassium permanganate. The iron factor of the per-
manganate multiplied by 1.429 gives the factor for Fe2O3.
The results multiplied by 5 gives the per cent, of iron oxide
in the sample.
Phosphoric Acid. — In another 100 cubic centimeters of the
solution the phosphoric acid is determined by precipitation
with molybdic acid solution. (For preparing the solution see
analysis of iron and steel.) Twenty to 25 cubic centimeters
are added to the 100 cubic centimeters of the nitrate from
the silica and transferred to a 300 cubic centimeter Erlen-
meyer flask. After vigorously shaking for 5 minutes, the
flask is stood aside for the precipitate to settle. After the
solution has cleared it is filtered through a close-grained
paper, the flask and precipitate are washed with a dilute solu-
tion of ammonium sulphate made slightly acid with sulphuric
acid. After washing it is redissolved in ammonia into the
flask in which it had been precipitated. It is then reduced
with zinc and titrated with standard permanganate solution
as under iron (for factor see Iron and Steel).
Alumina. — To the remaining 300 cubic centimeters add,
after transferring to a 600 cubic centimeter beaker, sufficient
ammonia to have a slight excess of the latter, boil off excess
and filter off the precipitated iron and aluminum oxides, wash
with water, dry and burn off in a tared porcelain crucible.
From the weight, subtract the iron oxide and phosphoric acid
previously determined. The rest is alumina.
Calcium. — To the filtrate from the iron and aluminum
oxides add a solution of ammonium oxalate, and heat to boil-
ing. The precipitated calcium oxalate is filtered off and
washed. The filter paper is next transferred to a weighed
porcelain crucible, a few drops of sulphuric acid are added,
224
and it is then dried and burned. The calcium oxide is calcu-
lated from the weight of the calcium sulphide thus formed.
Magnesia. — In the filtrate from the calcium oxalate the
magnesia is determined. The nitrate is first concentrated to
about 250 cubic centimeters. It is then cooled and placed in
a dish containing ice water. A solution of sodium ammo-
nium phosphate and about 30 cubic centimeters ammonia are
added, and the solution vigorously stirred. Care should be
taken not to touch the sides of the beaker with the rod. The
solution is left standing for about 10 hours, and the mag-
nesium pyrophosphate is then filtered and washed with a dilute
solution of ammonium nitrate made slightly alkaline with am-
monia. The precipitate of magnesium pyrophosphate is next
dried and burned and weighed as Mg2P2O7 from which the
MgO is calculated.
Alkalies. — For the alkalies place 2 grams of the finely
divided sample into a platinum dish, moisten with about 2
cubic centimeters of concentrated sulphuric acid, then add
hydrofluoric acid until reaction ceases. Add a small excess
and heat to drive off excess, until white fumes of sulphurous
acid are given off. Cool, add water, and wash into a beaker.
Add 10 cubic centimeters of hydrochloric acid and boil. Pre-
cipitate iron and alumina with ammonia, and then add a solu-
tion of ammonium oxalate to precipitate calcium, boil and
filter off precipitate and wash with hot water. Discard filter
paper and precipitate. Evaporate filtrate in a weighed plati-
num dish and after the solution has been evaporated to dry-
ness, heat over a Bunsen flame. The residue consists of al-
kaline and magnesium sulphates ; calculate the magnesium
previously determined to sulphate and deduct from weight of
dish. The difference between this corrected weight and the
original weight of the dish are alkaline sulphates.
Sulphur Trioxide. — Two grams of the finely divided sample
are for 12 hours digested in hydrochloric acid, to which potas-
sium chlorate is added. It is finally taken down to dryness,
redissolved in HC1, and the insoluble part filtered off. The
filtrate is heated to boiling, barium chloride added, and then
225
cooled. After the solution has cleared the barium sulphate is
filtered, washed, transferred to a weighed crucible and burned.
From the weight, the sulphur trioxide is calculated.
Titanium.
To determine titanic acid, treat 2 grams of the finely ground
clay in a large platinum crucible with hydrofluoric acid and 5
cubic centimeters of sulphuric acid. Evaporate off the hydro-
fluoric acid and heat carefully until the greater part of the sul-
phuric acid is volatilized. Allow the crucible to cool, add 10
grams of sodium carbonate, and fuse for 30 minutes at the
highest temperature obtainable by a Bunsen burner. Run the
fused mass well up on the sides of the crucible, and allow it to
cool. Treat the fused mass with water, transfer it to a
beaker, and filter. Wash the insoluble matter slightly on the
filter, dry, ignite, and fuse it again with sodium carbonate.
Dissolve in water as before, and filter. By this method of
treatment nearly all of the alumina will be dissolved and sepa-
rated from the titanic acid. Fuse the insoluble matter left on
the filter with sodium carbonate. Dissolve in hot water, filter
off insoluble ferric oxide, etc., acidulate with HC1, add a few
drops of acid ammonium sulphite, boil off all smell of sul-
phurous acid, and pass hydrogen sulphide, through the hot
solution to precipitate any arsenic that may be present. Pass
a current of carbonic acid through the solution to expel the
excess of hydrogen sulphide, filter off the arsenious sulphide,
and to the filtrate add a sufficient amount of ferric chloride
solution to combine with all the phosphoric acid as ferric
phosphate and leave a slight excess. Add a slight excess of
ammonia, which should throw down a red precipitate, while
the solution is alkaline to test-paper; then add acetic acid to
slightly acid reaction, boil, filter off the ferric phosphate and
ferric oxide, and wash with hot water. Acidulate the filtrate
with HC1, add ammonia until a permanent precipitate forms,
redissolve with a few drops of hydrochloric acid, add a fil-
tered solution of 20 grams of sodium acetate and one-sixth the
volume of the solution of acetic acid (1.04 specific gravity)
226
and heat to boiling. The titanic acid is precipitated almost
immediately in a flocculent condition and quite free from iron.
Boil a few minutes, allow the titanic acid to settle, filter, wash
with hot water containing a little acetic acid, dry, ignite, and
weigh as titanic acid, which contains 60.05 per cent, titanium.
Should the precipitate contain an appreciable amount of ferric
oxide, fuse with bisulphate and reprecipitate in the same way.
The essential points in this method are: I. Separation of
the titanic acid from the mass of ferric oxide by ammonium
acetate in the deoxidized solution. 2. Separation from all the
phosphoric acid and the greater part of the alumina by fusion
with sodium carbonate, by which means a sodium titanate in-
soluble in water is formed, and at the same time sodium phos-
phate and aluminate soluble in that menstruum. 3. Separation
of the last traces of alumina from the ferric oxide, lime, etc.,
by precipitating the titanic acid in the thoroughly deoxidized
solution in the presence of a large excess of acetic acid and
some sulphurous acid, the sulphuric acid being all in the form
of sodium sulphate. The addition of a large excess of sodium
acetate, by which this latter condition is effected, converts all
the sulphate into acetates, and precipitates the titanic acid al-
most instantaneously as a hydrate, which is flocculent, settles
quickly, shows no tendency to run through the filter, and is
washed with the greatest ease. It sometimes happens that a
little ferrous oxide is precipitated with the titanic acid, and
the latter, after ignition, appears discolored; in this case fuse
with a little sodium carbonate, add sulphuric acid to the cold
fused mass, dissolve, and repeat the precipitation with sodium
acetate in the presence of sulphurous and acetic acids exactly
as in the first instance.
The above titanium method is taken from "The Chemical
Analysis of Iron," by Blair.
Sutton gives the following volumetric method :
H. L,. Wells and W. L. Mitchell, in a contribution to the
Jour. Amer. Chem. Soc. 1895, 878, allude to a volumetric
method of determining titanic acid by Pisani (Compt. Rend,
lix. 289) which does not appear to have been found satis-
227
factory. Marignac (Zeit., anal. Cheni. vii. 112) applied
Pisani's method in the estimation of titanic acid in the presence
of niobic acid, special conditions being adopted to avoid the
reduction of the latter.
The authors have modified Pisani's process as improved by
Marignac, and employ it for the determination of iron together
with the titanic acid in ores. Sulphuric acid solutions are
used, and the liquid is protected from the air during cooling
and titration by means of a current of carbon dioxide.
Process. — Five grams of the pulverized ore are treated with
100 cubic centimeters of concentrated hydrochloric acid in a
covered beaker, using a gradually increasing heat, and
adding more acid if necessary.1 When there is no further
action, 50 cubic centimeters of a mixture of equal volumes of
sulphuric acid and water are added, and the liquid evaporated
until it fumes strongly. After cooling, 200 cubic centimeters
o*f water are added, the whole heated until the sulphates dis-
solve, and the liquid filtered into a liter flask. If anything be-
sides silicious matter is left on the filter paper, it should be
fused with potassium bisulphate, treated with concentrated
sulphuric acid, and the sulphates dissolved in hot water and
added to the main solution.
The liquid in the flask is made up to the mark with water,
and four portions of 200 cubic centimeters each taken, two
in Erlenmeyer flasks (500 cubic centimeters), and the other
two in ordinary 350 cubic centimeter flasks. Each of these
represents I gram of the ore.
To determine the iron, H2S is passed into the solutions in
the ordinary flasks to saturation, after which they are boiled
until all the H2S has been removed, care being taken to avoid
any contact of the solution with the air by covering the mouths
of the flasks with crucible lids. The flasks are then quickly
filled to the neck with cold recently-boiled water, rapidly
cooled, transferred to large beakers, and titrated with standard
potassium permanganate.
1 For refractories it appears advisable to treat with HF1 and H2SO4,
and then continue as above.
228
To the solutions in the Erlenmeyer flasks 25 cubic centi-
meters of concentrated sulphuric acid are added, and 3 or 4
rods of pure zinc, about 5 millimeters long and 6 or 7 milli-
meters in diameter are suspended in the liquid by means of a
platinum wire attached to the loop of a porcelain crucible lid,
which is inverted over the mouth of the flask. The liquid is
then gently boiled for 30 or 40 minutes. Then, without in-
terrupting the boiling, a rapid current of CO2 is introduced
tinder the cover. The flask is now rapidly cooled, the zinc
washed with a jet of water and removed, and the solution
titrated with permanganate, while the current of CO2 is still
being passed in. The difference between the permanganate
used in this case and that required for the iron alone, repre-
sents the amount corresponding to the titanic acid. The fac-
tor for metallic iron divided by 0.7 gives the factor for titanic
acid (TiO2).
The most convenient strength for the permanganate solu-
tion is one of 7.9 grams per liter, corresponding to about 0.014
gram of metallic iron.
In the determination of iron by reduction with sulphureted
hydrogen, no effect is produced on cold permanganate solu-
tion by the precipitated sulphur present, but precipitated sul-
phides, such as copper sulphide, should be filtered off before
boiling.
The results of test analyses of recrystallized potassium ti-
tanofluoride were somewhat low, but probably quite as good
or better than any gravimetric method.
RUBRICATING OIL.
A good lubricant should meet the following, generally ac-
cepted requirements :
1 i ) It must be free from corrosive elements such as acids,
either of mineral, animal or vegetable origin.
(2) It must have body enough to form and retain a fila-
ment of the lubricant over the lubricated parts to prevent
direct contact of the metal.
229
(3) A minimum coefficient of friction.
(4) High boiling-point to insure the proper flash and fire
points.
(5) Freedom from grit or tarry matter.
(6) Must not gum, due to presence of readily oxidizable
oils.
(7) Must not contain thickener.
(8) Must have a low volatility at comparatively high tem-
peratures.
(9) Must not become too thin when heated.
(10) Should not freeze or become thickened by moderately
low temperatures.
To determine the above qualities the following chemical,
physical, and mechanical tests are applied :
Chemical Tests:
1. Iodine Absorption.
2. Acidity.
3. Color Reactions.
4. Saponification.
5. Soap Test.
6. Tarry Matter and Grit.
Physical Tests:
1. Flash and Fire Tests.
2. Viscosity.
3. Specific Gravity.
4. Cold Test.
5. Index of Refraction.
Mechanical Test:
i. Coefficient of Friction.
Twenty-five grams of iodine and 30 grams of mercuric
chloride are each dissolved in 500 cubic centimeters of 95 per
cent, alcohol, uniting the two solutions, and allowing to stand
several hours before use. It is then standardized by IO/N
thiosulphate sodium solution. The process of the determina-
tion of the iodine absorption of an oil is as follows: One-
tenth to 0.5 gram of the fat or oil is dissolved in 10 cubic
230
centimeters of purest chloroform in a well-stoppered flask, and
20 cubic centimeters of the iodine solution added. The
amount must be finally regulated so that after not less than
two hours digestion the mixture possesses a dark brown tint;
under any circumstances it is necessary to have a considerable
excess of iodine (at least double the amount absorbed ought to
be present), and the digestion should be from 6 to 8 hours.
Some potassium iodide solution is then added, and the whole
diluted with 150 cubic centimeters of water, and IO/N thio-
sulphate solution delivered in until the color is nearly dis-
charged. Starch is then added, and the titration finished in
the usual way.
Acidity: (a) Fatty Acids in Compounded Oils. — Dissolve
10 grams of the oil in 50 cubic centimeters of absolute alcohol
and warm, add a drop of phenolphthalein and titrate with
N/5O soda solution until red appears. Calculate Mg. NaOH
required to neutralize I gram of oil.
(&) Free Acid in Mineral Oil. — In a separatory funnel
shake 25 cubic centimeters of the oil with 50 cubic centi-
meters of hot water, to which a drop of methyl orange has
been added. The water must not turn red.
Color Reaction: Heidenreich's test is as follows : A clear
glass plate is placed over a piece of white paper; 10 drops of
the oil under examination are placed thereon, and I drop of
concentrated sulphuric acid is added.
The color produced when the acid comes in contact with
the oil is noticed as well as the color produced when the two
are stirred with a glass rod. Many oils give off characteristic
odors during the reaction, especially neatsfoot oil, whale oil,
and menhaden oil.
Massie's test is thus performed :
Nitric acid of 1.40 specific gravity, free from nitrous acid
is mixed in a test-tube with y$ its volume of the oil, and the
whole agitated for 2 minutes.
The color of the oil after separation from the acid is the
indication.
In mixture of oils, the characteristic colors produced, by
231
either Heindenreich's or Massie's test are often clouded, and
in many instances no inference can be drawn, yet with single
oils the reactions are often distinctive and sufficiently strong
to give confirmatory results.
In cod liver oil, or w^hale oil, when mixed with mineral or
even vegetable oil, the characteristic brilliant violet color pro-
duced with sulphuric acid cannot be mistaken. This color,
due to the presence of cholic acid, is found in most of the fish
oils, but is much more pronounced in cod liver oil.
Heidenreich's Test
Massie's Test
Lard Oil
Yellow
Brown
Yellow
Tallow Oil
Yellow
Orange
Colorless
Neatsfoot Oil
Yellowish
Red-brown
Red
Oleo Oil Colorless
Orange
Pink
Elain Oil
Light green turn-
Brown
Orange Red
ing to brown
Sperm Oil
Brown with pur-
Reddish brown
Red
ple streaks
Whale Oil
Red-violet
Brown
Dark red
Dog-fish Oil
Cod liver Oil
Violet
Red-violet
Dark Brown
Dark Brown
Orange
Orange-red
Crude Cottonseed
Brilliant red
Brown
Brown
Ref'd Cottonseed
Reddish brown
Red
Orange- red
Rape Oil
Yellow-brown
Brown
Orange
Castor Oil
Light yellow to
Pale brown
Orange
brown
Olive Oil
Light green
Greenish to light
Yellow to green-
brown
ish
Rosin
Brown
Brown
Orange
Earth Nut Oil
Yellow to Orange
Greenish
Reddish
Saponification: (a) Separation of the Mineral Oil. — Ten
grams of the oil are weighed in a dry weighed beaker (250
cubic centimeters), and to it are added 75 cubic centimeters
of an alcoholic solution of potash (60 grams of potassium hy-
droxide to 1,000 cubic centimeters of 95 per cent, alcohol),
and the contents evaporated until all the alcohol is driven off.
In this process, if any animal or vegetable oil is present, it is
formed into a soap by the potash, while the mineral oil is un-
acted upon. Water (75 cubic centimeters) is now added and
the material well stirred to insure complete solution of the
soap, and then it is transferred to a separatory funnel, 75
232
cubic centimeters of sulphuric ether added, corked, the liquid
violently agitated and allowed to stand for 12 hours. Two
distinct liquids are now seen, the lower, the solution of the
soap, the upper the ether solution (colored, if mineral oil is
present, colorless if not). The aqueous solution is drawn off
in a No. 3 beaker, the ethereal solution remaining in the sep-
aratory funnel. The former is placed on a water bath, heated
for y2 .hour, and until all traces of ether (which is absorbed
by the water in a very small amount) is gone. The solution
is allowed to cool, diluted somewhat with water, and made
acid with dilute sulphuric acid. Any animal or vegetable oil
present will be indicated by a rise of the fatty acids to the
surface of the liquid. (In this reaction the sulphuric acid
decomposes the soap, uniting with the potash to form sulphate
of potash and liberating the fatty acids of the oil.)
If it is desired to weigh the fatty acids, proceed as follows :
Weigh carefully about 5 grams of pure white beeswax,
place it in the beaker upon the surface of the oil and water,
and bring the contents nearly to boiling; the melted wax and
fatty acids unite; allow to cool, remove the wax, wash with
water, dry between folds of filter paper, and weigh. The in-
crease in weight of the wax over its original weight gives the
weight of the fatty acids of the animal or vegetable oil in the
lubricating oil.
(b) Saponification Value. — This is expressed by the number
of milligrams of potassium hydrate necessary to saponify I
gram of the oil. From 2.5 to 10 grams of the oil, according
to the percentage of saponifiable matter supposed to be pres-
ent, are boiled with 25 cubic centimeters of N/2 alcoholic
potash in a 200 cubic centimeter Jena Erlenmeyer flask. A
reflux condenser is used, and the boiling may require from 5
to 8 hours. The excess of alkali is titrated with N/2 HC1,
using phenolphthalein. The strength of the N/2 KOH is de-
termined by boiling 25 cubic centimeters in similar flasks
alongside of those in which the oil is treated and for the same
length of time.
Tarry Matter and Grit. — Shake 10 cubic centimeters of the
233
oil with 90 cubic centimeters of petroleum ether in a test
tube, holding 125 cubic centimeters. No deposit should ap-
pear after standing for i hour.
Flash and Fire Test. — In a porcelain evaporating dish filled
with sand, place a platinum crucible, suspend a thermometer
reading at least 600° F. from a support directly above the
crucible so that the mercury bulb will reach to about the
middle of the crucible, care being taken not to touch the
sides. Fill the crucible with oil, completely covering the bulb
of the thermometer but allowing room for the oil to expand
without overflowing on heating. Adjust the flame so that the
temperature of the liquid in the dish rises at the rate required
for the liquid being tested, and when the temperature reaches
a desired point, apply the test flame by passing it slowly, en-
tirely across the dish, about a half inch above the level of the
liquid and just in front of the thermometer. Allow the liquid
to rise in temperature until another testing point is reached
and then apply the test flame again in the same manner. Pro-
ceed in this way until the vapor from the liquid above it ignites
with a slight flash. The temperature shown by the thermom-
eter when this is the case is the flashing point of the liquid.
Continue the heating and testing in the same manner until a
point is reached where the liquid takes fire. The reading of
the thermometer when this is the case is the burning point of
the liquid.
The test flame can best be adjusted by using a jeweler's
blowpipe and allowing enough gas to flow to produce a flame
of 2 to 3 millimeters long.
Viscosity. — The viscosity is generally determined by the
rate of flow at a specified temperature through an opening of
accurate standard size. It is recorded in seconds for a speci-
fied temperature and volume.
By comparison with standards an oil may be rated as to its
viscosity thus giving one of the values required for a lubri-
cant. Engler's apparatus — probably the first used for this
purpose — is made of metal (copper). This instrument is the
standard for determining the viscosity of oil in Germany, and
234
is also a standard in this country. It is recommended by the
United States Bureau of Standards for use unless another
form of viscosimeter is called for in the specification.
In using this instrument, the viscosity of an oil is stated in
seconds required for 200 cubic centimeters of the oil to run
into the flask. Two hundred and forty cubic centimeters of
the oil being placed in the viscosimeter, water usually requir-
ing from 50 to 53 seconds at 20° C. Heat can be applied to
the water bath, the viscosity being determined at any tem-
perature up to 1 00° C. Higher temperatures to 360° C. can
be secured by filling the outer vessel with paraffine instead of
water. Engler recommends that all viscosities be compared
with water thus : If water requires 52 seconds for delivery of
200 cubic centimeters into the receiving flask, and the same
amount of the oil under examination requires 130 seconds,
the ratio is determined by • - = 2.50, the oil thus having
a viscosity of 2.5 times that of water.
The American Society for Testing Materials, Report of
Committee D-2, state as follows :
In case it is desired to correct for specific gravity of the oil,
the following formula which gives the results in specific vis-
cosity can be used :
time of efflux of oil
Sp. viscosity == Sp. grav. X timeofeffluxofwater >- 7-32.
If it is necessary to use a quantity of oil less than 240 cubic
centimeters, the following quantities can be employed and
multiplied by the corresponding factor:
Amount of oil put in, cc. 45 50 60 120
Amount of oil run out, cc. 25 40 50 100
Factor to change to 200 cc. run
out and 240 cc. put in 5.55 3.62 2.79 1.65
The Committee recommends the use of the Saybold vis-
cosimeter. In this country it is the most widely used stand-
ard and has the advantage that small samples of 125 cubic
centimeters are sufficient for the test. This instrument is
shown in Fig. 58. The tests are carried out in practically the
235
same way as in the Engler, only that a flask graduated to 60
cubic centimeters is used for the receiver, and the seconds re-
quired for the oil to fill the flask to the 60 cubic centimeter
mark indicate the viscosity.
FIG. 58.
Specific Gravity.— -Lubricating oils are practically always
reported in degrees Baume. It is, therefore, sufficient to read
the gravity by means of a hydrometer, correcting for tempera-
ture. If the oil is too thick to float the hydrometer, heat to
90° or 1 00° F. The following table can be used for tempera-
ture corrections :
r-^00* ON O —• cs* ro -^ LOO t^-00* ON o' M cs ro TT Tf LOO t^-X ON O* HI ^ co-^f
,_ w „ cs CS CM CM CS CM CM CM CM CS CO CO CO ro CO CO CO CO rO tO CO •* >q- Tf -3- ^3-
00 00 00 00 f^
•H M O O ON ON ON ONOO OO
o t- r-o v v \ 10 u •«*• TJ- ^t- •* ro to
00 (^ O *-< fi ^O ^J" LO^O r-^-OO O\ O\ O •—
r-c « 01 CS M CS P) M CM <N CM <N <N l»,C«5
oo' ON O H! cs co TJ- 10^0 rix ON O HI' cs co co tf iCvO r^oo ONO 1-1 cs to T LO ,C r^
i-. M cs CS cs cs cs CS CS CM CM CM rOrOrOrorOror^r^cOrOrOT-^-Tj-^-Tj-Tr-^-Tr
vq \o up 10 •* ri- •* •* ro co M N N ej M — q q q q q\ CTNOO oq oc oo r>. r>. t
00 CT\ 6 M pi ro TJ- i/xo r^-od ON O - ' '
w M <N CS N M N N CS CN CM CM rOrO
00* ON O M cs rO ^}- LOO* r^-OO ON o M CM ro TJ- LOO) r^-OO* O^ O *H CM ro rO •**" to^O* r^.
w X CS CM CM CM CS CM CS CM CM CM cOrOrOt^cO rO CO CO CO CO'J-Tf<a-Tj-Tr-^-Tj-'3-Tj-
oo' oV O i-i cs' co TJ- LOO r^oc ON O *-" cs' c^ ^ LOO' t^-oo' ON O *-. fvj ro "^ LOO r^oo
M M CM CM CM CS CS CS CS CM CM CM COCOCOrOCOcOcOcOCOcO^"1^<^^*^'TfTj-Tf1^-
OO* ONO >-! <** rOTfLOO* t^-CO ON O* •—' CM ro T^- LOO' r^-OC ^ O ^ cs" ro -^ LOO* t^ 00*
O O ON ON ON ONOO ,xi 00 OO 00 OO
ON O « CM' ro rf lovd vO r^-oc cf\ O «' CM' rO rt- tO^O l^-oo' ON O -' CM' rO -<j- lOsd t^-cri
w CM CM CM CM CM CM CS CS CS CM CS COt^COrOrOrOCOrOrOrOTT-<3--^-T}-->rTr-^-i3--^-
cscMMi-iMi-iHMp-i)-iqqqqqqONONq^qNON ONOC oq oq oq oq oq r^. r^. t--.
ON o' >-< cs' ro TJ- LO\O t^-oo' ON o' M cs" ro -4- TJ- ir>\6 t-^-od <?• 6 >- cs ro -^- LOO' i^-oo'
1-1 CM CS CM CM CM CS CS CS CM CM rOCOrOrOrOCOCOfOrOrOCO-S-Tj-Tj-Ti-Tj-Ttf-Tr^-Tj-
O\ O ^ CM rO "^" *OO' t-^00* ON O HI CM ro -^ LOO' r^-GO O\ O HI CM* CO ^ LOO* r^-OO ON
ON o" HI (N ro ^f LOO" r-*-Oo" ON O* •-. cs' CO ^t" LO\O t^-00 ON O* ^ CM" rO rf LOO r~--00' ON
HI CM CS CM CMM CM CS CM CS CM P> IO fO W tO W ««*>«*> tO *•* <T ^r1"*-^ **r* •«*
oq c
(>0 HI CS
ONONONONONONONONONONONONON ONOO OO 00 00 00 00 00 00 OO 00 00 00 CO OO 00 OO OO
'
q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q
< O •*•> O HI CM CO TT LOOI t^OO ON O M CM co •* LO>O t^OO O^ O M cs rO TT LOO r^oC ON O
< *"• CU ^ ^ N N ^ ^ ^ ^ ^ ^ rorOrOcOrOcOrOcOcocO^'^'^-Tf^-'^-^-Tj-Tj-T^-LO
"^
237
Cold Test. — Twenty cubic centimeters of the oil are trans-
ferred to a narrow bottle or test tube, stoppered with a rubber
stopper, through which is inserted a thermometer, the bulb of
which remains an inch or more into the oil.
The bottle is placed in a mixture of ice and salt, or other
freezing compound, and retained there until the oil becomes
solid. It is then removed and allowed to warm until the con-
tents become somewhat thinner in consistency. The bottle is
inclined from side to side until the oil begins to flow, when
the temperature is taken.
At this particular temperature the oil is neither at its nor-
mal fluidity, nor is it solid, and while this method does not
correctly indicate the exact temperature of the solidify ing-
point, it does show the point at which the oil ceases to flow
readily, the important one to the oil inspector.
These methods are in part taken from Stillman's "Analysis
of Lubricating Oil."
SOLDER.
Tin and Antimony Determination.
Tin Determination. — Dissolve 0.5 gram of very finely di-
vided sample (best done with hacksaw) in 50 cubic centi-
meters of concentrated hydrochloric acid till action ceases,
passing a stream of CO2 gas, during the whole operation to
prevent oxidation, cool, still, passing CO2. Add starch paste
and titrate with IO/N iodine solution. Cubic centimeters used
x 1.18 = per cent. tin.
Antimony Determination. — Dissolve 0.5 gram metal in hy-
drochloric acid (as in tin determination, except not using CO2
gas). After action ceases, add small quantities of iodine
crystals. Boil off excess iodine, cool, dilute to 150 cubic
centimeters (put in 500 cubic centimeter flask), add 50 cubic
centimeters of Rochelle salt solution (10 — 20 grams salt in
the 50 cubic centimeters of water, keep cold, and nearly neu-
tralize with sodium bicarbonate, then completely neutralize
with sodium hydrate, keep cold (using litmus paper). Add
16
238
quickly concentrated sodium bicarbonate solution till milky.
Add starch paste and titrate with lo/N iodine solution. Cubic
centimeters used x 1.2 = per cent, antimony.
Lead is seldom determined but instead is taken by differ-
ence. It may, however, be determined by the method described
under Babbitt.
One-tenth normal iodine solution: 6.35 grams iodine and 9
grams of potassium iodine to 500 cubic centimeters of water.
HARD L,E)AD AND BABBITT.
To determine antimony in hard lead, the method for Babbitt
metal can be used.
To Determine Copper and Lead. — Five-tenth gram of the
finely divided sample in nitric acid adding 0.5 gram of chem-
ically pure copper (to avoid sponging of the lead on the
cathods) evaporate until almost dry and redissolve in 88
cubic centimeters of nitric acid with 50 cubic centimeters of
distilled water, filter, wash well with water and electrolyze
(see Copper Alloys), deduct the 0.5 gram C added from your
weight of the cathods, the remainder in the C in the Babbitt.
The increase of the weight of the annode multiplied by 0.868
x 2 x 100 gives the lead as metallic lead.
COPPER AU.OYS.
Weigh out I gram of the clean borings into a 250 cubic
centimeter beaker, dissolve in 20 cubic centimeters of diluted
nitric acid and evaporate to dryness.
Redissolve with 10 cubic centimeters concentrated nitric
acid and 40 cubic centimeters of water and filter off the oxide
of tin, running the filtrate into a 250 cubic centimeter beaker,
wash well with distilled water and fill the beaker to within l/2
inch of the top.
The solution is then electrolyzed by placing two platinum
electrodes previously weighed and connected with a 4-volt
direct current (storage battery or Edison Laland cells are
best fitted for the purpose) at a rate of about y2 ampere per
239
hour. After about 10 to 12 hours all of the copper will be
deposited on the negative electrode as metallic copper, the
lead on the positive electrode as. black peroxide. The elec-
trolyte is then quickly removed by lowering the beaker and
washed by replacing it with a beaker of distilled water and
then a beaker of alcohol. The electrodes are then dried and
weighed. The increase gives the per cent, of copper direct;
the lead is calculated by multiplying the weight of the oxide
with 0.868.
The oxide of tin is burned off and weighed. The weights
multiplied by 0.7881 gives the per cent, of metallic tin.
To the electrolyte from the electrolysis, ammonia is added
until decidedly ammoniacal, boil off excess and filter off any
iron hydroxide present, burn off and weigh. If zinc is present,
precipitate with hydrogen sulphide, filter and burn to zinc
oxide, weigh and calculate to metallic zinc.
In alloys containing nickel, the electrolyte after the copper
has been deposited and weighed is made alkaline with an ex-
cess of ammonia and the electrode coated with the copper re-
placed and a current of 6 volts passed through it to deposit
the nickel as metallic nickel. It is advisable to use the copper
plated cathod, since the nickel when deposited direct on the
platinum is hard to remove.
LIME.
In works practice the analysis is confined to determine the
quality of the lime as a binder for mortar and as an alkaline
for setting free ammonia from its fixed salts.
A high percentage of calcium oxide is most desirable and
the determination of CaO therefore suffices for most purposes.
In selecting the sample, about a bucket full of lumps are
quickly broken up into pieces the size of a pea, and quartered
down until one-quarter fills approximately a pint bottle ; pre-
caution should be taken to prevent the sample from absorbing
moisture or CO2 from the air.
One hundred grams of this sample are weighed into a i
240
liter flask. The sample is next slaked and the flask filled to
the mark with water and well shaken.
One hundred cubic centimeters of this milk of lime, with-
out letting it settle are transferred to another liter flask again
filled to the mark and well shaken. Fifty cubic centimeters
of this solution are transferred to an Erlenmeyer flask of 250
cubic centimeters capacity, adding a few drops of phenace-
tolin as an indicator, and titrated with normal hydrochloric
acid solution until the solution becomes a faint pink. The
caustic lime is calculated from the number of cubic centi-
meters of HC1 neutralized.
FIG. 59.
The titration is then continued until the solution changes
first to red and finally to yellow, the second titration giving the
241
carbonate of lime. It is sometimes desirable to determine the
unburned lime by determining the CO2 and calculating it
therefrom. It can best be done by means of an alkalimeter.
See Fig. 59.
FIG. 60.
The latter consists of a glass vessel having a glass stoppered
opening at the side through which the sample is introduced,
a separatory funnel with a glass stopper at one side of the
top and a gas scrubbing tube at the other.
To use the apparatus the gas scrubbing tube is first filled y$
full with concentrated sulphuric acid. The separatory fun-
242
nel is then filled with diluted HC1 (y2 acid, y2 water) and the
apparatus weighed.
Then approximately 5 grams of the powdered sample are in-
troduced through the glass stoppered opening and the whole
is again weighed. The acid in the separating funnel is next
FIG. 61.
run into the vessel through the stop-cock, and after the reac-
tion ceases, the flask is slightly warmed. After cooling it is
again weighed. The difference between the second and third
weights represents the CO2 driven off. By dividing the differ-
ence between the first and second weight (the weight of the
243
sample), into the third and mutliplied by 100, the percentage of
CO, is found and the percentage of calcium carbonate can be
calculated therefrom.
MAGNESIUM.
For the determination of magnesium follow scheme under
Refractories or Water Analysis.
Efficiency Test. For Use in Ammonia Still. — Five grams
of the sample are placed in a Kjeldahl flask and slaked. The
flask is next connected with the condenser of an ammonia dis-
tilling apparatus.
Through a separatory funnel are then added 10 grams of
ammonium sulphate previously dissolved in water. The am-
monia liberated on boiling is absorbed in a beaker containing
standard sulphuric acid. The operation is the same as in the
determination of ammonia in ammoniacal liquors.
From the ammonia thus determined, the efficiency of the
lime can be determined as follows :
a = NH3 found
b = CaO used
f* X 56\
\ 34 '
b
CO2 IN AIR.
For the determination of CO2 in air, there are two appara-
tuses generally used, the one is Haldane's (Fig. 60) and the
other Patterson's (Fig. 61). These apparatuses differ from
the Orsat apparatus that the gas volume can be read as close
as o.ooi of a cubic centimeter and CO2 can, therefore, be
determined in o.oooi by volume.
CEMENT.
STANDARD SPECIFICATIONS FOR CEMENT, AS PUBLISHED BY
THE AMERICAN SOCIETY FOR TESTING MATERIALS.
Adopted, 1904; Revised, 1908, 1909.
GENERAL OBSERVATIONS.
i. These remarks have been prepared with a view of point-
244
ing out the pertinent features of the various requirements and
the precautions to be observed in the interpretation of the
results of the tests.
2. The Committee would suggest that the acceptance or
rejection under these specifications be based on tests made by
an experienced person having the proper means for making
the tests.
SPECIFIC GRAVITY.
3. Specific gravity is useful in detecting adulteration. The
results of tests of specific gravity are not necessarily conclu-
sive as an indication of the quality of a cement, but when in
combination with the results of other tests may afford valu-
able indications.
FINENESS.
4. The sieves should be kept thoroughly dry.
TIME OF SETTING.
5. Great care should be exercised to maintain the test pieces
under as uniform conditions as possible. A sudden change or
wide range of temperature in the room in which the tests are
made, a very dry or humid atmosphere, and other irregulari-
ties vitally affect the rate of setting.
• CONSTANCY OF VOLUME.
6. The tests for constancy of volume are divided into two
classes, the first normal, the second accelerated. The latter
should be regarded as a precautionary test only, and not in-
fallible. So many conditions enter into the making and inter-
preting of it that it should be used with extreme care.
7. In making the pats the greatest care should be exercised
to avoid initial strains due to molding or to too rapid drying-
out during the first 24 hours. The pats should be preserved
under the most uniform conditions possible, and rapid changes
of temperature should be avoided.
8. The failure to meet the requirements of the accelerated
245
tests need not be sufficient cause for rejection. The cement may,
however, be held for 28 days, and a retest made at the end of
that period, using a new sample. Failure to meet the require-
ments at this time should be considered sufficient cause for
rejection, although in the present state of our knowledge it
cannot be said that such failure necessarily indicates unsound-
ness, nor can the cement be considered entirely satisfactory
simply because it passes the tests.
SPECIFICATIONS.
General Conditions.
1. All cement shall be inspected.
2. Cement may be inspected either at the place of manu-
facture or on the work.
3. In order to allow ample time for inspecting and testing,
the cement should be stored in a suitable weather-tight build-
ing having the floor properly blocked or raised from the
ground.
4. The cement shall be stored in such a manner as to permit
easy access for proper inspection and identification of each
shipment.
5. Every facility shall be provided by the Contractor and a
period of at least 12 days allowed for the inspection and nec-
essary tests.
6. Cement shall be delivered in suitable packages with the
brand and name of manufacturer plainly marked thereon.
7. A bag of cement shall contain 94 pounds of cement net.
Each barrel of Portland cement shall contain four bags, and
each barrel of natural cement shall contain three bags of the
above net weight.
8. Cement failing to meet the 7-day requirements may be
held awaiting the results of the 28-day tests before rejection.
9. All tests shall be made in accordance with the methods
proposed by the Committee on Uniform Tests of Cement of
the American Society of Civil Engineers, presented to the So-
ciety January 21, 1903, and amended January 20, 1904, and
246
January 15, 1908, with all subsequent amendments thereto.
(See addendum to these specifications.)
10. The acceptance or rejection shall be based on the fol-
lowing requirements:
Natural Cement.
11. Definition. — This term shall be applied to the finely pul-
verized product resulting from the calcination of an argillace-
ous limestone at a temperature only sufficient to drive off the
carbonic acid gas.
FINENESS.
12. It shall leave by weight a residue of not more than 10
per cent, on the No. 100, and 30 per cent, on the No. 200 sieve.
TIME oi? SETTING.
13. It shall not develop initial set in less than 10 minutes;
and shall not develop hard set in less than 30 minutes, or in
more than 3 hours.
TENSILE STRENGTH.
14. The minimum requirements for tensile strength for bri-
quets i square inch in cross section shall be as follows, and
the cement shall show no retrogression in strength within the
periods specified :
Neat Cement.
Age Strength
24 hours in moist air 75 pounds
7 days (i day in moist air, 6 days in water) 150 pounds
28 days (i day in moist air, 27 days in water) 250 pounds
One Part Cement, Three Parts Standard Ottawa Sand.
7 days (i day in moist air, 6 days in water) 50 pounds
28 days (i day in moist air, 27 days in water) 125 pounds
CONSTANCY OF VOLUME.
15. Pats of neat cement about 3 inches in diameter, y2 inch
thick at center, tapering to a thin edge, shall be kept in moist
air for a period of 24 hours.
(a) A pat is then kept in air at normal temperature.
247
(b) Another is kept in water maintained as near 70° F. as
practicable.
1 6. These pats are observed at intervals for at least 28 days,
and, to satisfactorily pass the tests, shall remain firm and hard
and show no signs of distortion, checking, cracking, or disinte-
grating.
Portland Cement.
17. Definition. — This term is applied to the finely pulverized
product resulting from the calcination to incipient fusion of
an intimate mixture of properly proportioned argillaceous and
calcareous materials, and to which no addition greater than
3 per cent, has been made subsequent to calcination.
SPECIFIC GRAVITY.
1 8. The specific gravity of cement shall not be less than
3.10. Should the test of cement as received fall below this
requirement, a second test may be made upon a sample ignited
at a low red heat. The loss in weight of the ignited cement
shall not exceed 4 per cent.
FINENESS.
19. It shall leave by weight a residue of not more than 8
per cent, on the No. 100, and not more than 25 per cent, on the
No. 200 sieve.
TIME OF SETTING.
20. It shall not develop initial set in less than 30 minutes;
and must develop hard set in not less than i hour, nor more
than 10 hours.
TENSILE STRENGTH.
21. The minimum requirements for tensile strength for bri-
quets I square inch in cross section shall be as follows, and
the cement shall show no retrogression in strength within the
periods specified:
248
Neat Cement.
Age Strength
24 hours in moist air 175 pounds
7 days (i day in moist air, 6 days in water) 500 pounds
28 days (i day in moist air, 27 days in water) 600 pounds
One Part Cement, Three Parts Standard Ottawa Sand.
7 days (i day in moist air, 6 days in water) 200 pounds
28 days (i day in moist air, 27 days in water) 275 pounds
CONSTANCY OF VOLUME.
22. Pats of neat cement about 3 inches in diameter, y2 inch
thick at the center, and tapering to a thin edge, shall be kept
in moist air for a period of 24 hours.
(a) A pat is then kept in air at normal temperature and ob-
served at intervals for at least 28 days.
(b) Another pat is kept in water maintained as near 70°
F. as practicable, and observed at intervals for at least 28
days.
(c) A third pat is exposed in any convenient way in an
atmosphere of steam, above boiling water, in a loosely closed
vessel for 5 hours.
23. These pats, to satisfactorily pass the requirements, shall
remain firm and hard, and show no signs of distortion, check-
ing, cracking, or disintegrating.
SULPHURIC ACID AND MAGNESIA.
24. The cement shall not contain more than 1.75 per cent,
of anhydrous sulphuric acid (SO3), nor more than 4 per cent,
of magnesia (MgO).
ADDENDUM.
METHODS FOR TESTING CEMENT.1
Recommended by the Special Committee on Uniform Tests of Cement
of the American Society of Civil Engineers.
SAMPLING.
i. Selection of Sample. — The selection of samples for testing
should be left to the engineer. The number of packages sampled and
1 Accompanying Final Report of Special Committee on Uniform Tests of Cement
of the American Society of Civil Engineers, dated January 17, 1912.
249
the quantity taken from each package will depend on the importance
of the work and the facilities for making the tests.
2. The samples should fairly represent the material. When the
amount to be tested is small it is recommended that I barrel in 10 be
sampleti ; when the amount is large it may be impracticable to take
samples from more than I barrel in 30 or 50. When the samples are
taken from bins at the mill I for each 50 to 200 barrels will suffice.
3. Samples should be passed through a sieve having twenty meshes
per linear inch, in order to break up lumps and remove foreign mate-
rial; the use of this sieve is also effective to obtain a thorough mixing
of the samples when this is desired. To determine the acceptance or
rejection of cement it is preferable, when time permits, to test the
samples separately. Tests to determine the general characteristics of
a cement, extending over a long period may be made with mixed
samples.
4. Method of Sampling, — Cement in barrels should be sampled
through a hole made in the head, or in one of the staves midway
between the heads, by means of an auger or a sampling iron similar to
that used by sugar inspectors; if in bags, the sample should be taken
from surface to center; cement in bins should be sampled in such a
manner as to represent fairly the contents of the bin. Sampling from
bins is not recommended if the method of manufacture is such that
ingredients of any kind are added to the cement subsequently.
CHEMICAI, ANALYSIS.
5. Significance. — Chemical analysis may serve to detect adultera-
tion of cement with inert material, such as slag or ground limestone,
if in considerable amount. It is useful in determining whether certain
constituents, such as magnesia and sulphuric anhydride, are present in
inadmissible proportions.
6. The determination of the principal constituents of cement, silica,
alumina, iron oxide, and lime, is not conclusive as an indication of
quality. Faulty cement results more frequently from imperfect prepa-
ration of the raw material or defective burning than from incorrect
proportions. Cement made from material ground very finely and
thoroughly burned may contain much more lime than the amount
usually present, and still be perfectly sound. On the other hand,
cements low in lime may, on account of careless preparation of the raw
material, be of dangerous character. Furthermore, the composition of
the product may be so greatly modified by the ash of the fuel used in
burning as to affect in a great degree the significance of the results
of analysis.
25°
7. Methods. — The methods to be followed, except for determining
the loss on ignition, should be those proposed by the Committee on
Uniformity in the Analysis of Materials for the Portland Cement
Industry, reported in the Journal of the Society for Chemical Industry,
Vol. 21, p. 12, 1902; and published in Engineering News, Vol. 50, p. 60,
1903; and in Engineering Record, Vol. 48, p. 49, 1903, and in addition
thereto, the following :
(a) The insoluble residue may be determined as follows : To a
i -gram sample of the cement are added 30 cubic centimeters of water
and 10 cubic centimeters of concentrated hydrochloric acid, and then
warmed until effervescence ceases, and digested on a steam bath until
dissolved. The residue is filtered, washed with hot water, and the
filter paper and contents digested on the steam bath in a 5 per cent,
solution of sodium carbonate. This residue is filtered, washed with
hot water, then with hot hydrochloric acid, and finally with hot water,
and then ignited at a red heat and weighed. The quantity so obtajped
is the insoluble residue.
(b) The loss on ignition shall be determined in the following
manner: One-half gram of cement is heated in a weighed platinum
crucible, with cover, for 5 minutes with a Bunsen burner (starting with
a low flame and gradually increasing to its full height) and then heated
for 15 minutes with a blast lamp; the difference between the weight
after cooling and the original weight is the loss on ignition. The
temperature should not exceed 900° C., or a low red heat; the ignition
should preferably be made in a muffle.
SPECIFIC GRAVITY.
8. Significance. — The specific gravity of cement is lowered by
adulteration and hydration, but the adulteration must be considerable
to be detected by tests of specific gravity.
9. Inasmuch as the differences in specific gravity are usually very
small, great care must be exercised in making the determination.
10. Apparatus. — The determination of specific gravity should be
made with a standardized Le Chatelier apparatus. This consists of a
flask (D), Fig. 62, of about 120 cubic centimeters capacity, the neck
of which is about 20 centimeters long; in the middle of this neck is a
bulb (C), above and below which are two marks (F) and (£) ; the
volume between these two marks is 20 cubic centimeters. The neck
has a diameter of about 9 millimeters, and is graduated into tenths of
cubic centimeters above the mark (/•*)•
11. Benzine (62° Baume naphtha) or kerosene free from water
should be used in making the determination.
12. Method. — The flask is filled with either of these liquids to the
lower mark (B), and 64 grams of cement, cooled to the temperature
of the liquid, is slowly introduced through the funnel (B}, the stem of
251
which should be long enough to extend into the flask to the top of the
bulb (Oi taking care that the cement does not adhere to the sides
of the flask, and that the funnel does not touch the liquid. After all
the cement is introduced, the level of the liquid will rise to some
division of the graduated neck; this reading, plus 20 cubic centimeters,
is the volume displaced by 64 grams of the cement.
FIG. 62.— Le Chatelier's Specific Gravity Apparatus.
\
13. The specific gravity is then obtained from the formula,
Weight of cement, in grams,
Specific gravity =
Displaced volume, in cubic centimeters.
14. The flask, during the operation, is kept immersed in water in a
jar (A), in order to avoid variations in the temperature of the liquid
in the flask, which should not exceed J4° C. The results of repeated
tests should agree within o.oi. The determination of specific gravity
252
should be made on the cement as received ; if it should fall below
3.10, a second determination should be made after igniting the sample
in a covered dish, preferably of platinum, at a low red heat not exceed-
ing 900° C. The sample should be heated for 5 minutes with a Bunsen
burner (starting with a low flame and gradually increasing to its full
height) and then heated for 15 minutes with a blast lamp; the ignition
should preferably be made in a muffle.
15. The apparatus may be cleaned in the following manner : The
flask is inverted and. shaken vertically until the liquid flows freely, and
then held in a vertical position until empty ; any traces of cement
remaining can be removed by pouring into the flask a small quantity
of clean liquid benzine or kerosene and repeating the operation.
FINENESS.
16. Significance. — It is generally accepted that the coarser particles
in cement are practically inert, and it is only the extremely fine powder
that possesses cementing qualities. The more finely cement is pul-
verized, other conditions being the same, the more sand it will carry
and produce a mortar of a given strength.
17. Apparatus. — The fineness of a sample of cement is determined
by weighing the residue retained on certain sieves. Those known as
No. 100 and No. 200, having approximately 100 and 200 wires per linear
inch, respectively, should be used. They should be 8 inches in diam-
eter. The frame should be of brass, 8 inches in diameter, and the
sieve of brass wire cloth conforming to the following requirements:
No. of sieve
Diameter of wire,
inches
Meshes, per linear inch
Warp
Woof
100
2OO
0.0042 to 0.0048
O.OO2I to O.OO23
95 to IOI
192 to 203
93 to 103
190 to 205
The meshes in any smaller space, down to 0.25 inch, should be pro-
portional in number.
18. Method. — The test should be made with 50 grams of cement,
dried at a temperature of 100° C (212° F.).
19. The cement is placed on the No. 200 sieve, which, with pan and
cover attached, is held in one hand in a slightly inclined position, and
moved forward and backward about 200 times per minute, at the same
time striking the side gently, on the up stroke, against the palm of the
other hand. The operation is continued until not more than 0.05 gram
will pass through in I minute. The residue is weighed, then placed
253
on the No. 100 sieve, and the operation repeated. The work may be
expedited by placing in the sieve a few large steel shot, which should
be removed before the final I minute of sieving. The sieves should
be thoroughly dry and clean.
NORMAI, CONSISTENCY.
20. Significance. — The use of a proper percentage of water in
making pastes1 and mortars for the various tests is exceedingly impor-
tant and affects vitally the results obtained.
FIG. 63.— Vicat Apparatus.
21. The amount of water, expressed in percentage by weight of the
dry cement, required to produce a paste of plasticity desired, termed
1 The term "paste" is used in this report to designate a mixture of cement and
water and the word "mortar" to designate a mixture of cement, sand and water.
17
254
"normal consistency," should be determined with the Vicat apparatus
in the following manner:
22. Apparatus. — This consists of a frame (A}, Fig. 63, bearing a
movable rod (B), weighing 300 grams, one end (C) being I centimeter
in diameter for a distance of 6 centimeters, the other having a remov-
able needle (D), I millimeter in diameter, 6 millimeters long. The
rod is reversible, and can be held in any desired position by a screw
(B), and has midway between the ends a mark (F) which moves
under a scale (graduated to millimeters) attached to the frame (A).
The paste is held in a conical, hard-rubber ring (G), 7 centimeters in
diameter at the base, 4 centimeters high, resting on a glass plate (//)
about 10 centimeters square.
23. Method. — In making the determination, the same quantity of
cement as will be used subsequently for each batch in making the test
pieces, but not less than 500 grams, with a measured quantity of water,
is kneaded into a paste, as described in paragraph 45, and quickly
formed into a ball with the hands, completing the operation by tossing
it six times from one hand to the other, maintained about 6 inches
apart; the ball resting in the palm of one hand is pressed into the
larger end of the rubber ring held in the other hand, completely filling
the ring with paste ; the excess at the larger end is then removed by a
single movement of the palm of the hand; the ring is then placed on
its larger end on a glass plate and the excess paste at the smaller end
is sliced off at the top of the ring by a single oblique stroke of a
trowel held at a slight angle with the top of the ring. During these
operations care must be taken not to compress the paste. The paste
confined in the ring, resting on the plate, is placed under the rod, the
larger end of which is brought in contact with the surface of the
paste; the scale is then read, and the rod quickly released.
24. The paste is of normal consistency when the cylinder settles
to a point 10 millimeters below the original surface in l/2 minute after
being released. The apparatus must be free from all vibrations during
the test.
25. Trial pastes are made with varying percentages of water until
the normal consistency is obtained.
26. Having determined the percentage of water required to pro-
duce a paste of normal consistency, the percentage required for a
mortar containing, by weight, I part of cement to 3 parts of standard
Ottawa sand, is obtained from the following table, the amount .being
a percentage of the combined weight of the cement and sand.
255
PERCENTAGE OF WATER FOR STANDARD MORTARS.
One cement,
One cement,
One cement,
Neat
three standard
Neat
three standard
Neat
three standard
Ottawa sand
Ottawa sand
Ottawa sand
15
8.0
23
9-3
31
10.7
16
8.2
24
9-5
32
10.8
17
8-3
25
9-7
33
II.O
18
8.5
26
9.8
34
II. 2
19
8.7
27
10.0
35
ii. 3
20
8.8
28
10.2
36
H.5
21
9.0
29
10.3
37
11.7
22
9.2
30
10.5
38
11.8
TIME OE SETTING.
27. Significance. — The object of this test is to determine the time
which elapses from the moment water is added until the paste ceases
to be plastic (called the "initial set"), and also the time until it acquires
a certain degree of hardness (called the "final set" or "hard set").
The former is the more important, since, with the commencement of
setting, the process of crystallization begins. As a disturbance of this
process may produce a loss of strength, it is desirable to complete the
operation of mixing or molding or incorporating the mortar into the
work before the cement begins to set.
28. Apparatus. — The initial and final set should be determined
with the Vicat apparatus described in paragraph 22.
29. Method. — x\ paste of normal consistency is molded in the hard
rubber ring, as described in paragraph 23, and placed under the rod
(B), the smaller end of which is then carefully brought in contact
with the surface of the paste, and the rod quickly released.
30. The initial set is said to have occurred when the needle ceases
to pass a point 5 millimeters above the glass plate; and the final set,
when the needle does not sink visibly into the paste.
31. The test pieces should be kept in moist air during the test;
this may be accomplished by placing them on a rack over water con-
tained in a pan and covered by a damp cloth ; the cloth to be kept from
contact with them by means of a wire screen; or they may be stored
in a moist box or closet.
32. Care should be taken to keep the needle clean, as the collection
of cement on the sides of the needle retards the penetration, while
cement on the point may increase the penetration.
33. The time of setting is affected not only by the percentage and
temperature of the water used and the amount of kneading the paste
receives, but by the temperature and humidity of the air, and its deter-
mination is, therefore, only approximate.
256
STANDARD SAND.
34. The sand to be used should be natural sand from Ottawa, 111.,
screened to pass a No. 20 sieve, and retained on a No. 30 sieve. The
sieves should be at least 8 inches in diameter; the wire cloth should
be of brass wire and should conform to the following requirements :
No. of sieve
Diameter of wire,
inches
Meshes, per linear inch
Warp
Woof
2O
30
0.016 to 0.017
O.OII tO O.OI2
19.5 to 20.5
29.5 to 30.5
19 to 21
28.5 to 31.5
FIG. 64.— Details for Briquet.
257
Sand which has passed the No. 20 sieve is standard when not more
than 5 grams passes the No. 30 sieve in I minute of continuous sift-
ing of a 5oo-gram sample.1
FORM OF TEST PIECES.
35. For tensile tests the form of test piece shown in Fig. 55 should
be used.
36. For compressive tests, 2-inch cubes should be used.
MOLDS.
37. The molds should be of brass, bronze, or other non-corrodible
material, and should have sufficient metal in the sides to prevent
spreading during molding.
38. Molds may be either single or gang molds. The latter are pre-
ferred by many. If used, the types shown in Figs. 65 and 66 are
recommended.
FIG. 65.— Details for Gang Mold.
FIG. 66. -Mold for Compression Test Pieces.
39. The molds should be wiped with an oily cloth before using.
MIXING.
40. The proportions of sand and cement should be stated by
weight; the quantity of water should be stated as a percentage by
weight of the dry material.
41. The metric system is recommended because of the convenient
relation of the gram and the cubic centimeter.
42. The temperature of the room and of the mixing water should
be maintained as nearly as practicable at 21° C. (70° F.).
* This sand may now (1912) be obtained from the Ottawa Silica Co., at a cost of two
cents per pound, f. o. b. cars, Ottawa, 111.
258
43. The quantity of material to be mixed at one time depends on
the number of test pieces to be made; 1,000 grams is a convenient quan-
tity to mix by hand methods.
44. The Committee has investigated the various mechanical mix-
ing machines thus far devised, but cannot recommend any of them,
for the following reasons: (i) the tendency of most cement is to
"ball up" in the machine, thereby preventing working it into a homo-
geneous paste; (2) there are no means of ascertaining when the mix-
ing is complete without stopping the machine; and (3) it is difficult
to keep the machine clean.
45. Method. — The material is weighed, placed on a non-absorbent
surface (preferably plate glass), thoroughly mixed dry if sand be
used, and a crater formed in the center, into which the proper per-
centage of clean water is poured ; the material on the outer edge is
turned into the center by the aid of a trowel. As soon as the water
has been absorbed, which should not require more than i minute, the
operation is completed by vigorously kneading with the hands for
i minute. During the operation the hands should be protected by
rubber gloves.
MOLDING.
46. The Committee has not been able to secure satisfactory results
with existing molding machines ; the operation of machine molding is
very slow; and is not practicable with pastes or mortars containing as
large percentages of water as herein recommended.
47. Method. — Immediately after mixing, the paste or mortar is
placed in the molds with the hands, pressed in firmly with the fingers,
and smoothed off with a trowel without ramming. The material should
be heaped above the mold, and, in smoothing off, the trowel should be
drawn over the mold in such a manner as to exert a moderate pressure
on the material. The mold should then be turned over and the opera-
tion of heaping and smoothing off repeated.
48. A check on the uniformity of mixing and molding may be
afforded by weighing the test pieces on removal from the moist closet;
test pieces from any sample which vary in weight more than 3 per cent,
from the average should not be considered.
STORAGE OF THE TEST PIECES.
49. During the first 24 hours after molding, the test pieces should
be kept in moist air to prevent drying.
50. Two methods are in common use to prevent drying: (i) cov-
ering the test pieces with a damp cloth, and (2) placing them in a
moist closet. The use of the damp cloth, as usually carried out, is
objectionable, because the cloth may dry out unequally and in conse-
259
quence the test pieces will not all be subjected to the same degree of
moisture. This defect may be remedied to some extent by immersing
the edges of the cloth in water; contact between the cloth and the
test pieces should be prevented by means of a wire screen, or some
similar arrangement. A moist closet is so much more effective in
securing uniformly moist air, and is so easily devised and so inexpen-
sive, that the use of the damp cloth should be abandoned.
Roller turned and accurately
bored to easy turning fit
FIG. 67.— Form of Clip.
51. A moist closet consists of a soapstone or slate box, or a wooden
box lined with metal, the interior surface being covered with felt or
broad wicking kept wet, the bottom of the box being kept covered
with water. The interior of the box is provided with glass shelves on
which to place the test pieces, the shelves being so arranged that they
may be withdrawn readily.
260
52. After 24 hours in moist air, the pieces to be tested after longer
periods should be immersed in water in storage tanks or pans made
of non-corrodible material.
53. The air and water in the moist closet and the water in the
storage tanks should be maintained as nearly as practicable at 21° C.
(70° P.).
TENSILE STRENGTH.
54. The tests may be made with any standard machine.
55. The clip is shown in Fig. 67. It must be made accurately, the
pins and rollers turned, and the rollers bored slightly larger than the
pins so as to turn easily. There should be a slight clearance at each
end of the roller, and the pins should be kept properly lubricated and
free from grit. The clips should be used without cushioning at the
points of contact.
56. Test pieces should be broken as soon as they are removed from
the water. Care should be observed in centering the test pieces in
the testing machine, as cross strains, produced by imperfect centering,
tend to lower the breaking strength. The load should not be applied
too suddenly, as it may produce vibration, the shock from which often
causes the test pieces to break before the ultimate strength is reached.
The bearing surfaces of the clips and test pieces must be kept free
from grains of sand or -dirt, which would prevent a good bearing. The
load should be applied at the rate of 600 pounds per minute. The
average of the results of the test pieces from each sample should be
taken as the test of the sample. Test pieces which do not break within
J4 inch of the center, or are otherwise manifestly faulty, should be
excluded in determining average results.
COMPRESSIVE STRENGTH.
57. The tests may be made with any machine provided \vith means
for so applying the load that the line of pressure is along the axis of
the test piece. A ball-bearing block for this purpose is shown in
Fig. 68. Some appliance should be provided to facilitate placing the
axis of the test piece exactly in line with the center of the ball-bearing.
58. The test piece should be placed in the testing machine, with a
piece of heavy blotting paper on each of the crushing faces, which
should be those that were in contact with the mold.
CONSTANCY OF VOLUME.
59. Significance. — The object is to detect those qualities which tend
to destroy the strength and durability of a cement. Under normal
conditions these defects will in some cases develop quickly, and in
26 1
•other cases may not develop for a considerable time. Since the detec-
tion of these destructive qualities before using the cement in con-
struction is essential, tests are made not only under normal conditions
but under artificial conditions created to hasten the development of
these defects. Tests may, therefore, be divided into two classes :
(i) Normal tests, made in either air or water maintained, as nearly
-as practicable, at 21° C. (70° F.) ; and (2) Accelerated tests, made in
^%££^%^
FIG. 68.— Ball-bearing Block for Testing Machine.
air, steam or water, at temperature of 45° C. (113° F.) and upward.
The Committee recommends that these tests be made in the following
manner :
60. Methods. — Pats, about 3 inches in diameter, % inch thick at
the center, and tapering to a thin edge, should be made on clean glass
plates (about 4 inches square) from cement paste of normal consist-
ency, and stored in a moist closet for 24 hours.
61. Normal Tests. — After 24 hours in the moist closet, a pat is
immersed in water for 28 days and observed at intervals. A similar
262
pat, after 24 hours in the moist closet, is exposed to the air for 28 days
or more and observed at intervals.
62. Accelerated Test.— After 24 hours in the moist closet, a pat is
placed in an atmosphere of steam, upon a wire screen I inch above
boiling water, for 5 hours. The apparatus should be so constructed
that the steam will escape freely and atmospheric pressure be main-
tained. Since the type of apparatus used has a great influence on the
results, the arrangement shown in Fig. 69 is recommended.
63. Pats which remain firm and hard and show no signs of crack-
ing distortion, or disintegration are said to be "of constant volume"
or "sound."
64. Should the pat leave the plate, distortion may be detected best
with a straight-edge applied to the surface which was in contact with
the plate.
65. In the present state of our knowledge it cannot be said that a
cement which fails to pass the accelerated test will prove defective in
the work ; nor can a cement be considered entirely safe simply because
it has passed these tests.
METHODS FOR TESTING CEMENT.1
Condensed for Use in Specifications.
i. SAMPLING.
Cement in barrels shall be sampled through a hole made in the
head, or in one of the staves midway between the heads, by means of
an auger or a sampling iron similar to that used by sugar inspectors;
if in bags, the sample shall be taken from surface to center. Cement
in bins shall be sampled in such a manner as to represent fairly the
contents of the bin. The number of samples taken shall be as directed
by the engineer, who will determine whether the samples shall be
tested separately or mixed.
The samples shall be passed through a sieve having twenty meshes
per linear inch, in order to break up lumps and remove foreign
material.
2. CHEMICAL, ANALYSIS.
The methods to be followed, except for determining the loss on
ignition, should be those proposed by the Committee on Uniformity
in the Analysis of Materials for the Portland Cement Industry, re-
ported in the Journal of the Society for Chemical Industry, Vol. 21,
p. 12, 1902, and published in Engineering News, Vol. 50, p. 60, 1903,
and in Engineering Record, Vol. 48, p. 49, 1903, and in addition thereto
the following:
1 Accompanying Final Report of Special Committee on Uniform Tests of Cement
of the American Society of Civil Engineers, dated January 17, 1912.
263
*
fed
\
If
1
• .
i ^
^ i
llJ_
» t
ir^
^ §
\ !
( ^ ^.l-ft— - >
! K;*-
:— 7,9—
i
•
!
I
•
j
1 kl IFTj
//
i
Re
\
°5
il
111
*\i
ill
/
rrHfe
^r-F
S oJ
|i
li
5^
2 rr
264
(a) The insoluble residue may be determined as follows : To a
i -gram sample of the cement are added 30 cubic centimeters of water
and 10 cubic centimeters of concentrated hydrochloric acid, and then
warmed until effervescence ceases, and digested on a steam bath until
dissolved. The residue is filtered, washed with hot water, and the
filter paper and contents digested on the steam bath in a 5 per cent,
solution of sodium carbonate. This residue is filtered, washed with
hot water, then with hot hydrochloric acid, and finally with hot water,
and then ignited at a red heat and weighed. The quantity so obtained
is the insoluble residue.
(&) The loss on ignition shall be determined in the following
manner : One-half gram of cement is heated in a weighed platinum
crucible, with cover, for 5 minutes with a Bunsen burner (starting
with a low flame and gradually increasing to its full height) and then
heated for 15 minutes with a blast lamp; the difference between the
weight after cooling and the original weight is the loss on ignition.
The temperature should not exceed 900° C., or a low red heat ; the
ignition should preferably be made in a muffle.
3. SPECIFIC GRAVITY.
The determination of specific gravity shall be made with a stand-
ardized Le Chatelier apparatus. This consists of a flask (D), Fig. 62,
p. 251, of about 120 cubic centimeters capacity, the neck of which is
about 20 centimeters long; in the middle of this neck is a bulb (C),
above and below which are two marks (F) and (B) ; the volume
between these two marks is 20 cubic centimeters. The neck has a
diameter of 9 millimeters, and is graduated into tenths of cubic centi-
meters above the mark (F).
Benzene (62° Baume naphtha) or kerosene free from water shall
be used in making the determination. The flask is filled with either
of these liquids to the lower mark (£) and 64 grams of cement, cooled
to the temperature of the liquid, is slowly introduced through the
funnel (B), the stem of which should be long enough to extend into
the flask to the top of the bulb (C), taking care that the cement does
not adhere to the sides of the flask, and that the funnel does not touch
the liquid. After all the cement is introduced, the level of the liquid
will rise to some division of the graduated neck; this reading, plus
20 cubic centimeters, is the volume displaced by 64 grams of the
cement. The specific gravity is obtained from the formula,
Weight of cement, in grams
Spec ic gravity = Displaced volume> jn cubic centimeters.
The flask, during the operation, is kept immersed in water in a
jar (A) in order to avoid variations in the temperature of the liquid
in the flask, which shall not exceed T/2° C. The results of repeated
tests shall agree within o.oi. The determination of specific gravity
shall be made on the cement as received; if it should fall below 3.10,
a second determination shall be made after igniting the sample in a
covered dish, preferably of platinum, at a low red heat not exceeding
900° C. The sample shall be heated for 5 minutes with a Bunsen
burner (starting with a low flame and gradually increasing to its full
height) and then heated for 15 minutes with a blast lamp; the ignition
should preferably be made in a muffle.
4. FINENESS.
The fineness shall be determined by weighing the residue retained
on No. 100 and No. 200 sieves. The sieves, 8 inches in diameter, shall
be of brass wire cloth conforming to the following requirements :
No. of sieve
Diameter of wire,
inches
Meshes, per linear inch
Warp
Woof
100
200
0.0042 to 0.0048
0.0021 to 0.0023
95 to ioi
192 to 203
93 to 103
190 to 205
The meshes in any smaller space, down to 0.25 inch, shall be pro-
portional in number.
Fifty grams of cement, dried at a temperature of 100° C. (212° F.),
shall be placed on the No. 200 sieve, which, with pan and cover
attached, is held in one hand in a slightly inclined position, and moved
forward and backward about 200 times per minute, at the same time
striking the side gently, on the up stroke, against the palm of the other
hand. The operation is continued until not more than 0.05 gram will
pass through in I minute. The residue is weighed, then placed on the
No. 100 sieve, and the operation repeated. The work may be expedited
by placing in the sieve a few large steel shot, which should be removed
before the final I minute of sieving. The sieves should be thoroughly
dry and clean.
5. NORMAI, CONSISTENCY.
The amount of water, expressed in percentage by weight of the
dry cement, required to produce a paste1 of the plasticity desired,
termed "normal consistency," shall be determined with the Vicat
apparatus :
1 The term "paste" is used in these specifications to designate a mixture of cement
and water, and the word "mortar" to designate a mixture of cement, sand and water.
266
This consists of a frame (A), Fig. 63, p. 253, bearing a movable
rod (#), weighing 300 grams, one end (C) being I centimeter in
diameter for a distance of 6 centimeters, the other having a removable
needle (D), i millimeter in diameter, 6 centimeters long. The rod is
reversible, and can be held in any desired position by a screw (£),
and has midway between the ends a mark (F) which moves under a
scale (graduated to millimeters) attached to the frame (A). The
paste is held in a conical, hard-rubber ring ((7), 7 centimeters in diam-
eter at the base, 4 centimeters high, resting on a glass plate (H ) about
10 centimeters square.
In making the determination of normal consistency, the same
quantity of cement as will be used subsequently for each batch in
making the test pieces, but not less than 500 grams, together with a
measured amount of water, is kneaded into a paste, as described in
Section 9, and quickly formed into a ball with the hands, completing
the operation by tossing it six times from one hand to the other, main-
tained about 6 inches apart; the ball resting in the palm of one hand
is pressed into the larger end of the rubber ring held in the other
hand, completely filling the ring with paste; the excess at the larger
end is then removed by a single movement of the palm of the hand;
the ring is then placed on its larger end on a glass plate and the excess
paste at the smaller end is sliced off at the top of the ring by a single
oblique stroke of a trowel held at a slight angle with the top of the
ring. During these operations care must be taken not to compress the
paste. The paste confined in the ring, resting on the plate, is placed
under the rod, the larger end of which is carefully brought in contact
with the surface of the paste ; the scale is then read, and the rod quickly
released.
The paste is of normal consistency when the cylinder settles to a
point 10 millimeters below the original surface in Y? minute after
being released. The apparatus must be free from all vibrations during
the test.
Trial pastes are made with varying percentages of water until the
normal consistency is attained.
Having determined the percentage of water required to produce
a paste of normal consistency, the percentage required for a mortar
containing, by weight, I part of cement to 3 parts of standard Ottawa
sand, shall be obtained from the following table, the amount being a
percentage of the combined weight of the cement and sand.
267
PERCENTAGE OF WATER FOR STANDARD MORTARS.
Neat
One cement,
three standard
Ottawa sand
Neat
One cement,
three standard
Ottawa sand
Neat
One cement,
three standard
Ottawa sand
15
8.0
23
9-3
31
10.7
16
8.2
24
9-5
32
10.8
17
8-3
25
9-7
33
II.O
18
8.5
26
9.8
34
II. 2
19
8.7
27
IO.O
35
"•3
2O
8.8
28
10.2
36
H-5
21
9.0
29
I0.3
37
ii. 7
22
9.2
30
10.5
38
ix.8
6. TIME; OF SETTING.
The time of setting shall be determined with the Vicat apparatus
in the following manner:
A paste of normal consistency is molded in the hard-rubber ring,
as described in Section 5, and placed under the rod (5), the smaller
end of which is then carefully brought in contact with the surface of
the paste, and the rod quickly released.
The cement is considered to have acquired its initial set when the
needle ceases to pass a point 5 millimeters above the glass plate ; and
the final set, when the needle does not sink visibly into the paste.
The test pieces must be kept in moist air during the test.
7. STANDARD SAND.
The sand shall be natural sand from Ottawa, 111., screened to pass
a No. 20 sieve, and retained on a No. 30 sieve.
The sieves shall be at least 8 inches in diameter, and the wire
cloth shall be of brass wire and shall conform to the following
requirements :
No. of sieve
Diameter of wire,
inches
Meshes, per linear inch
Warp
Woof
20
30
0.016 to 0.017
O.OII tO 0.012
19.5 to 20.5
29-5 to 30.5
19 tO 21
28.5 to 31.5
Sand which has passed the No. 20 sieve is standard when not more
than 5 grams pass the No. 30 sieve in I minute of continuous sifting
of a 5OO-gram sample.1
1 This sand may now (1912) be obtained from the Ottawa Silica Co., at a cost of two
cents per pound, f . o. b. cars, Ottawa, 111.
268
8. FORM OE TEST PIECES.
For tensile tests, the form of test pieces shown in Fig. 64, p. 256^.
shall be used.
For compressive tests, 2-inch cubes shall be used.
9. MIXING AND MOLDING.
The material shall be weighed, placed on a non-absorbent surface,
thoroughly mixed dry if sand be used, and a crater formed in the
center, into which the proper percentage of clean water shall be
poured; the material on the outer edge shall be turned into the center
by the aid of a trowel. As soon as the water has been absorbed, the
operation of mixing shall be completed by vigorously kneading with
the hands for I minute.
Immediately after mixing, the paste or mortar shall be placed in
the mold (Figs. 65 and 66, p. 257) with the hands, pressed in firmly
with the fingers, and smoothed off with a trowel without ramming.
The material shall be heaped above the mold, and, in smoothing off,,
the trowel shall be drawn over the mold in such a manner as to exert
a moderate pressure on the material ; the mold shall then be turned
over and the operation of heaping and smoothing off repeated.
The temperature of the room and of the mixing water shall be
maintained as nearly as practicable at 21° C. (70° F.).
10. STORAGE OF THE TEST PIECES.
During the first 24 hours after molding, the test pieces shall be
stored in a moist closet. This consists of a box of soapstone or slate,
or of wood lined with metal, the interior surface being covered with
felt or broad wicking kept wet, the bottom of the box being kept cov-
ered with water. The interior of the box is provided with glass
shelves on which to place the test pieces, the shelves being so arranged
that they may be withdrawn readily.
Test pieces from any sample which vary more than 3 per cent, in
weight from the average, after removal from the moist closet, shall
not be considered in determining strength.
After 24 hours in the moist closet, the pieces to be tested after
longer periods shall be immersed in water in storage 'tanks or pans
made of non-corrodible material.
The air and water in the moist closet and the water in the storage
tanks shall be maintained, as nearly as practicable, at 21° C. (70° F.).
11. TESTS OF TENSILE STRENGTH.
The tests may be made with any standard machine.
The clip is shown in Fig. 67, p. 259. It must be made accurately,
the pins and rollers turned, and the rollers bored slightly larger than
269
the pins so as to turn easily. There should be a slight clearance at
each end of the roller, and the pins should be kept properly lubricated
and free from grit. The clips shall be used without cushioning at
the points of contact.
The test pieces shall be broken as soon as they are removed from
the water. The load shall be applied at the rate of 600 pounds per
minute.
Test pieces which do not break within J4 inch of the center, or
are otherwise manifestly faulty, shall be excluded in determining
average results.
12. TESTS OF COMPRESSIVE STRENGTH.
The tests may be made with any machine provided with means
for so applying the load that the line of pressure is along the axis of
the test piece. A ball-bearing block for this purpose is shown in Fig.
68, p. 261.
The test pieces as soon as they are removed from the water shall
be placed in the testing machine, with a piece of heavy blotting paper
on each of the crushing faces, which should be those that were in
contact with the mold.
13. CONSTANCY OF VOLUME.
Tests for constancy of volume comprise "normal tests" which are
made in air or water, maintained as nearly as practicable,, at 21° C.
(70° F.), and the "accelerated test," which is made in steam. These
tests shall be made in the following manner :
Pats about 3 inches in diameter, ~*/2 inch thick at the center, and
tapering to a thir edge, shall be made on clean glass plates (about 4
inches square) from cement paste of normal consistency, and stored
in a moist closet for 24 hours.
Normal Tests. — After 24 hours in the moist closet, a pat is im-
mersed in water and observed at intervals. A similar pat, after 24
hours in the moist closet, is exposed to the air for 28 days or more
and observed at intervals. The air and water are maintained, as nearly
as practicable, at 21° C. (70° F.).
Accelerated Test. — After 24 hours in the moist closet, a pat is
placed in an atmosphere of steam, upon a wire screen I inch above
boiling water, for 5 hours, the apparatus being such that the steam
will escape freely and atmospheric pressure be maintained. The
apparatus is shown in Fig. 69, p. 263.
The cement passes these tests when the pats remain firm and
hard, with no signs of cracking, distortion, or disintegration.
18
270
APPENDIX.
METHODS FOR THE CHEMICAL ANALYSIS OF
LIMESTONES, RAW MIXTURES AND
PORTLAND CEMENTS.
Recommended by the Committee on Uniformity in Technical
Analysis of the New York Section of the Society
for Chemical Industry.
Solution. — One-half gram of the finely powdered substance is to-
be weighed out and, if a limestone or unburned mixture, strongly
ignited in a covered platinum crucible over a strong blast for 15
minutes, or longer if the blast is not powerful enough to effect com-
plete conversion to a cement in this time. It is then transferred to an
evaporating dish, preferably of platinum for the sake of celerity in
evaporation, moistened with enough water to prevent lumping, and
5 to 10 cubic centimeters of strong HC1 added and digested with the
aid of gentle heat and agitation until solution is complete. Solution
may be aided by light pressure with the flattened end of a glass rod.1
The solution is then evaporated to dryness, as far as this may be
possible on the bath.
Silica (5V02). — The residue without further heating is treated at
first with 5 to 10 cubic centimeters of strong HC1, which is then
diluted to half strength or less, or upon the residue may be poured at
once a larger volume of acid of half strength. The dish is then
covered and digestion allowed to go on for 10 minutes on the bath,
after which the solution is filtered and the separated silica washed
thoroughly with water. The filtrate is again evaporated to dryness,
the residue without further heating, taken up with acid and water and
the small amount of silica it contains separated on another filter paper.
The papers containing the residue are transferred wet to a weighed
platinum, crucible, dried, ignited, first over a Bunsen burner until the
carbon of the filter is completely consumed, and finally over the blast
for 15 minutes and checked by a further blasting for 10 minutes or
to constant weight. The silica, if great accuracy is desired, is treated
in the crucible with about 10 cubic centimeters of HF1 and four drops
of H2SO4 and evaporated over a low flame to complete dryness. The
small residue is finally blasted, for a minute or two, cooled and
weighed. The difference between this weight and the weight previously
obtained gives the amount of silica.2
1 If anything remains undecomposed it should be separated, fused with a little
Na2COo, dissolved and added to the original solution. Of course a small amount of
separated non-gelatinous silica is not to be mistaken for undecomposed matter.
2 For ordinary control in the plant laboratory this correction may, perhaps, be neg-
lected; the double evaporation never.
271
Alumina and Iron (A1203 and FezO3).— The filtrate, about 250
cubic centimeters, from the second evaporation for SiOz, is made alka-
line with NHUOH after adding HC1, if need be, to insure a total of
10 to 15 cubic centimeters strong acid, and boiled to expel excess
of NH3, or until there is but a faint odor of it, and the precipitate iron
and aluminum hydrates, after settling, are washed once by decanta-
tion and slightly on the filter. Setting aside the filtrate, the precipitate
is dissolved in hot dilute HC1, the solution passing into the beaker in
which the precipitation was made. The aluminum and iron are then
reprecipitated by NHUOH, boiled and the second precipitate collected
and washed on the same filter used in the first instance. The filter
paper, with the precipitate, is then placed in a weighed platinum
crucible, the paper burned off and the precipitate ignited and finally
blasted 5 minutes, with care to prevent reduction, cooled and weighed
as A12O3 -f FesOs.1
Iron (Fe^Os). — The combined iron and aluminum oxides are fused
in a platinum crucible at a very low temperature with about 3 to 4
grams of KHSO<, or, better, NaHSO-i, the melt taken up with so much
dilute H2SO4 that there shall be no less than 5 grams absolute acid
and enough water to effect solution on heating. The solution is then
evaporated and eventually heated till acid fumes come off copiously.
After cooling and redissolving in water the small amount of silica is
filtered out, weighed and corrected by HF1 and HzSCk2 The filtrate
is reduced by zinc, or preferably by hydrogen sulphide, boiling out
the excess of the latter afterwards while passing CO2 through the
flask, and titrated with permanganate.3 The strength of the perman-
ganate solution should not be greater than 0.0040 gram Fe2O3 per
cubic centimeter.
Lime (CaO).— To the combined filtrate from the A12O3 + Fe2O3
precipitate a few drops of NH4OH are added, and the solution brought
to boiling. To the boiling solution 20 cubic centimeters of a saturated
solution of ammonium oxalate are added, and the boiling continued
until the precipitated CaCaCX assumes a well-defined granular form.
It is then allowed to stand for 20 minutes, or until the precipitate has
settled, and then filtered and washed. The precipitate and filter are
placed wet in a platinum crucible, and the paper burned off over a
small flame of a Bunsen burner. It is then ignited, redissolved in
HC1, and the solution made up to 100 cubic centimeters with water.
1 This precipitate contains TiO2, P2O5, Mn3O4.
* This correction of A12O3 Fe2O3 for silica should not be made when the HF1 cor-
rection of the main silica has been omitted, unless that silica was obtained by only one
evaporation and nitration. After two evaporations and nitrations i to 2 mg. of SiO
are still to be found with the A12O3 Fe2O3.
3 In this way only is the influence of titanium to be avoided and a correct result
obtained for iron.
272
Ammonia is added in slight excess, and the liquid is boiled. If a small
amount of A12O3 separates this is filtered out, weighed, and the amount
added to that found in the first determination, when greater accuracy
is desired. The lime is then reprecipitated by ammonium oxalate,
allowed to stand until settled, filtered and washed,1 weighed as oxide
by ignition and blasting in a covered crucible to constant weight, or
determined with dilute standard permanganate.2
Magnesia (MgO). — The combined filtrates from the calcium pre-
cipitates are acidified with HC1 and concentrated on the steam bath to
about 150 cubic centimeters, 10 cubic centimeters of saturated solution
of Na(NH4)HPO4 are added, and the solution boiled for several
minutes. It is then removed from the flame and cooled by placing
the beaker in ice water. After cooling, NH4OH is added drop by
drop with constant stirring until the crystalline ammonium-magnesium
orthophosphate begins to form, and then in moderate excess, the
stirring being continued for several minutes. It is then set aside for
several hours in a cool atmosphere and filtered. The precipitate is
redissolved in hot dilute HC1, the solution made up to about 100
cubic centimeters, I cubic centimeter of a saturated solution of
Na(NH4)HPO4 added, and ammonia drop by drop, with constant
stirring until the precipitate is again formed as described and the
ammonia is in moderate excess. It is then allowed to stand for about
2 hours, when it is filtered on a paper or a Gooch crucible, ignited,
cooled and weighed as M^PaOi.
Alkalies (K20 and A^a20). — For the determination of the alkalies,
the well-known method of Prof. J. Lawrence Smith is to be followed,
either with or without the addition of CaCO3 with NH4C1.
Anhydrous Sulphuric Acid (SOa), — One gram of the substance is
dissolved in 15 cubic centimeters of HC1, filtered and residue washed
thoroughly.3
The solution is made up to 250 cubic centimeters in a beaker and
boiled. To the boiling solution 10 cubic centimeters of a saturated
solution of BaCl2 is added slowly drop by drop from a pipette and the
boiling continued until the precipitate is well formed, or digestion on
the steam bath may be substituted for the boiling. It is then set aside
over night, or for a few hours, filtered, ignited and weighed as BaSCX.
Total Sulphur. — One gram of the material is weighed out in a
large platinum crucible and fused with Na2COs and a little KNO3,
being careful to avoid contamination from sulphur in the gases from
source of heat. This may be done by fitting the crucible in a hole in
1 The volume of wash-water should not be too large; vide Hillebrand.
- The accuracy of this method admits of criticism, but its convenience and rapidity
demand its insertion.
3 Evaporation to dryness is unnecessary, unless gelatinous silica should have sep-
arated and should never be performed on a bath heated by gas; vide Hillebrand.
273
an asbestos board. The melt is treated in the crucible with boiling
water and the liquid poured into a tall narrow beaker and more hot
water added until the mass is disintegrated. The solution is then
filtered. The filtrate contained in a No. 4 beaker is to be acidulated
with HC1 and made up to 250 cubic centimeters with distilled water,
boiled, the sulphur precipitated as BaSO* and allowed to stand over
night or for a few hours.
Loss on Ignition. — Half a gram of cement is to be weighed out
in a platinum crucible, placed in a hole in an asbestos board so that
about three-fifths of the crucible projects below, and blasted 15 min-
utes, preferably with an inclined flame. The loss by weight, which is
checked by a second blasting of 5 minutes, is the loss on ignition.
May, 1903 : Recent investigations have shown that large errors
in results are often due to the use of impure distilled water and
reagents. The analyst should, therefore, test his distilled water by
evaporation and his reagents by appropriate tests before proceeding
with his work.
STEEL.
METHODS OF CHEMICAL ANALYSIS FOR PLAIN CARBON STEEL,
AS PUBLISHED BY THE AMERICAN SOCIETY
FOR TESTING MATERIAL.
ADOPTED, 1914.
DETERMINATION OF CARBON BY THE
DlRECT-COMBUSTION METHOD.
The method of direct combustion of the metal in oxygen
is recommended, the carbon dioxide obtained being absorbed
in barium-hydroxide solution, the precipitated barium carbon-
ate filtered off, washed, dissolved in a measured excess of
hydrochloric acid and the excess titrated against standard
alkali.
The use of potassium-hydroxide solution or soda lime for
the absorption of carbon dioxide, with suitable purifying train
following the furnace, is recognized as being capable of very
satisfactory refinement and as possessing merit where the time
element is of prime significance.
Owing to the diversity of apparatus by which correct results
may be obtained in the determination of carbon, the recom-
274
mendations are intended more to indicate what is acceptable
than to prescribe definitely what shall be used.
Apparatus.
Purifying Train. — The method employed eliminates the
necessity of a purifying train following the furnace, inasmuch
as no precautions are necessary to prevent access of water
vapor, or sulphur trioxide — the impurities usually guarded
against — from the absorbing apparatus. All that is needed is
a calcium-chloride tower filled with stick sodium hydroxide
placed before the furnace, or between the furnace and cata-
lyzer, if, as recommended, the latter is used for the purpose
of oxidizing organic matter in the oxygen.
Material for Lining Boats. — Alundum, "RR Alundum, al-
kali-free, specially prepared for carbon determination," as sup-
plied by dealers is suitable, and is recommended. The 90-
mesh or finer grades are used. Chromite, properly sized and
freed from materials causing a blank, may also be employed.
No substance containing alkali or alkaline earth metals, or car-
bon as carbonates or in other form, should be used as a lining
material. Quartz sand, owing to its liability to fuse or to slag
with the oxides of iron, causing bubbles of gas to be enclosed,
is objectionable. Aluminum oxide, made by calcining alum or
otherwise, often contains sulphate not easily destroyed, or may
contain objectionable substances of an alkaline nature.
Catalyzers. — Suitable catalyzers are copper oxide, platinized
quartz or asbestos, or platinum gauze. One of these should be
used in the forward part of the combustion apparatus, as well
as in the purifying train preceding the combustion tube (see
above). Platinized materials sometimes give off volatile sub-
stances on heating, and whatever material is used should not
be subject to this defect.
Combustion Apparatus. — Any apparatus heated by gas or
electricity which will bring the sample to a temperature of 950
to 1,100° C. may be used. Combustion tubes may be porce-
lain, glazed on one or both sides, quartz or platinum. Quartz
is liable to devitrification when used continuously at tempera-
275
tures above 1,000° C., and may then become porous. Com-
bustion crucibles of platinum may be heated by blast or by
Meker burners.
Boats or Other Containers of Samples being Burned. —
These may be of porcelain, quartz, alundum, clay, platinum,
or nickel, and should always receive a lining of granular alun-
dum.
Purifying Train before Combustion Apparatus. — This con-
sists of a tower filled with stick sodium hydroxide, preceded by
a catalyzer.
The Train after the Combustion Apparatus. — This consists
merely of the Meyer tube for absorption of the carbon dioxide,
protected by a soda-lime tube at the far end. Meyer tubes
with 7 to 10 bulbs of 10 to 15 cubic centimeter capacity each,
and large bulbs at the ends, having volumes equal to the com-
bined capacity of the small bulbs, have been used and found
satisfactory.
FIG. 70.— Apparatus for Filtration in Determination of Carbon by the
Direct-Combustion Method.
Filtering Apparatus. — In filtration for accurate work, care
should be taken to protect the solution from access of extra-
neous carbon dioxide. This is accomplished in the apparatus
shown in Fig. 70. For work requiring less accuracy, the barium
276
carbonate may be filtered off on a filter made by fitting a car-
bon funnel with a perforated porcelain disk and filtering by
suction. The precipitate is then washed with distilled water
from which the carbon dioxide has been removed by boiling.
Reagents.
Oxygen. — Oxygen of not less than 97 per cent, purity is
recommended. Endeavor should be made to obtain oxygen
which gives no blank, since the correction for or elimination of
this is troublesome and uncertain. For the most accurate
work, particularly with low-carbon products, such as ingot
iron, etc., the blank should be completely eliminated by the use
of a catalyzer before the furnace, with a carbon-dioxide ab-
sorbent interposed between furnace and catalyzer.
Tenth-normal Hydrochloric Acid. — This may be standard-
ized by any of the accepted methods, or as follows : Twenty
cubic centimeters of the approximately N/io acid is measured
out with a pipette, and the silver chloride precipitated by an
excess of silver-nitrate solution in a volume of 50 to 60 cubic
centimeters. After digesting at 70 to 80° C., until the super-
natant liquid is clear, the chloride is filtered off on a tared
Gooch filter and washed with water containing 2 cubic centi-
meters of nitric acid per 100 cubic centimeters of water until
freed from silver nitrate. After drying to constant weight
at 130° C., the increase of weight over the original tare is
noted and from this weight, corresponding to the silver chlo-
ride, the strength of the hydrochloric acid is calculated, after
which it is adjusted to the strength prescribed. The standard-
ization should be based upon several concordant determinations
using varying amounts of acid.
i cc. N/io HC1 = 0.0006 g. carbon.
Methyl Orange. — Dissolve 0.02 gram in 100 cubic centi-
meters of hot distilled water and filter.
Tenth-normal Sodium-Hydroxide Solution. — This is stand-
ardized against the hydrochloric acid. Methyl orange is used
as the indicator. The sodium-hydroxide solution should be
stored in a large bottle from which it may be driven out by air
277
pressure, protecting against carbon dioxide by soda-lime tubes.
Barium-Hydroxide Solution. — A saturated solution is fil-
tered and stored in a large reservoir from which it is delivered
by air pressure, protecting from carbon dioxide by a soda-lime
tube. Three or four small bulbs of the Meyer tube are filled,
and CO2-free water is added until the remaining small bulbs
are filled.
Factors Influencing Rapid Combustion.
Size of Particles of Sample. — The finer the chips the better,
except with samples which burn too vigorously (see under
"Rate of Admitting Oxygen"). Particles too coarse to pass
a 2O-mesh sieve are not recommended, nor long curly drillings
which will not pack closely. A ^-inch flat drill may be used
for taking the sample and the pressure and speed of the drill-
press regulated to secure the desired result ; or, better still, the
sample may be obtained with a small milling machine suitable
for sampling, or by a shaping machine. Oil, dust, and other
foreign matter should be carefully excluded.
Manner of Distributing Sample in Boat. — This is of con-
siderable importance. With all samples, close packing in a
small space is conducive to rapid combustion. In the case of
samples which burn too vigorously, a satisfactory regulation
may sometimes be attained by spreading the sample loosely
over the lining in the boat.
Rate of Admitting Oxygen. — The rate at which oxygen is
admitted is also a factor in the velocity of combustion. Assum-
ing the combustion apparatus to be heated to the temperature
range recommended above (950 to 1,100° C.), it is possible, if
the material is closely packed and if oxygen is admitted at too
rapid a rate, that the combustion may be so violent as to cause
excessive spattering of fused oxides, and such fluidity of the
molten slag that the boat or other container may be injured or
destroyed; therefore a moderate rate of burning is to be
sought. This is desirable also from the standpoint of the com-
plete absorption of the carbon dioxide by the barium-hydroxide
solution. The factors, temperature of combustion apparatus,
278
manner of distribution of sample, and rate of admission of
oxygen, can be governed so as to burn successfully steels of a
very wide range of compositions, in either fine or coarse
particles.
Method.
After having properly set up and tested the apparatus, place
2 grams of steel (see note No. i) in the form recommended
above, in a moderately packed condition on the bed material
and introduce the boat into the combustion apparatus, already
heated to the proper temperature. After about a minute (to
allow the sample and container to reach the temperature of the
furnace), admit oxygen somewhat more rapidly than it is con-
sumed, as shown by the rate of bubbling in the Meyer tube (see
note No. 2). The sample burns completely in i or 2 minutes,
and all that is now necessary is to sweep all the carbon dioxide
into the absorption apparatus. This can be accomplished in
6 to 8 minutes by passing about i or 2 liters of oxygen. De-
tach the Meyer tube (see note No. 2) and filter and wash the
barium carbonate, using the special filtering apparatus shown.
After solution in a measured excess of hydrochloric acid (the
Meyer tube being washed out with a portion of the acid, to
remove adhering barium carbonate), titrate the excess of acid
against alkali and from the data thus obtained calculate the
percentage of carbon.
NOTES.
1. When working with steels high in carbon (above I per cent.)
it is advisable not to use more than I gram in order that nitration may
be sufficiently rapid.
2. As a precaution against error resulting from too rapid passage
of the gases, it is well to attach a second barium-hydroxide tube to
retain any carbon dioxide that may pass the first.
3. For the most accurate work the Meyer tubes should be washed
with dilute acid before beginning work each day. After a determina-
tion is finished the tube should be completely filled two or three times
with tap water, then rinsed with distilled water, in order to remove
the carbon dioxide liberated when dissolving the carbonate from the
previous determination.
279
4. The flask containing the carbonate should be thoroughly agi-
tated after adding the acid, since the carbonate sometimes dissolves
rather slowly if this is not done ; this is particularly the case if it has
packed much during nitration.
Apparatus and Procedure for. Filtration.
The apparatus is shown to approximately one-tenth size in
Fig. 70, which is self-explanatory. The stop-cock is a three-
way cock connected to the suction pipe. The rubber tubing
connected to the Meyer tube should be of best-grade black
rubber, and the lengths used should be so chosen as to permit
of easy manipulation of the tube. The Meyer tube is con-
nected or disconnected by the rubber stoppers which are left
always attached to the rubber tubes. The carbon tube C is
fitted with a perforated porcelain plate sliding easily.
The funnel is prepared for filtration by making on the por-
celain disk a felt of asbestos about 1/16 to 1/8 inch in thickness,
using amphibole (not serpentine) asbestos which has been
carefully digested with strong hydrochloric acid for several
hours and washed with water until it gives no acid reaction.
On top of the asbestos pad is placed a layer of similarly treated
quartz, mixed with asbestos, of the height shown. A mixture
of quartz grains of various sizes (approximately 50 per cent,
passing a 2O-mesh sieve and 50 per cent, passing a lo-mesh and
remaining on a 2O-mesh sieve) is suitable. The mixture of
quartz and asbestos may be obtained by filling the funnel from
a beaker (directing against it a stream from a wash-bottle)
while maintaining a gentle suction. In this way the asbestos
is properly mixed with the quartz. A little experience and
attention to these details will enable one to prepare the quartz-
bed in a manner that will greatly expedite filtration. The
stopper is now inserted in the funnel, the Meyer tube connected
as shown and the liquid and precipitate sucked into the funnel.
Only a gentle suction should be used. When necessary P3 is
opened to admit air back of the column of liquid in the Meyer
tube. When the contents of the Meyer tube have been trans-
ferred, the large bulb nearest B is half filled with water by open-
ing PI ; the stop-cock $ is operated during this and subsequent
2&D
operations so as to maintain a gentle suction all the time. M
is now manipulated so as to bring the wash water in contact
with all parts of the interior, after which the water is sucked
through C; P2 is left open during this and subsequent wash-
ings. After eight washings as directed, allowing the wash
water to drain off thoroughly each time before adding more,
M may be detached, the stopper removed from the funnel and
the washings completed by filling C to the top with CO2-free
water, sucking off completely and repeating the operation once.
With care the washing may be done with 150 cubic centimeters
of water. Air is now admitted through the side opening of $,
C is removed and the porcelain disk carrying the asbestos,
quartz and barium carbonate is thrust, by means of a long glass
rod, into a flask, removing any adhering particles from the
sides of C, by a stream of water from a wash bottle. An ex-
cess of the standard acid is now added from a burette or
pipette, using a portion to wash out M, and after the contents
of the flask have been thoroughly agitated by shaking, the ex-
cess of acid is titrated against the standard alkali, using 3
drops of the methyl-orange indicator.
NOTES.
The operation of filtering can be carried out very rapidly after a
little practice.
Glass wool should on no account be used as a substitute for the
quartz, on account of the probability of errors arising from its attack
by the alkali or acid.
It is well to wash out the rubber tubes connected to the Meyer
tube with a little water each day before beginning work.
DETERMINATION OF CARBON BY THE COLORIMETRIC METHOD.
(Routine.)
Solution Required.
Nitric Acid. — Mix 1,000 cubic centimeters of nitric acid,
specific gravity 1.42, and 1,200 cubic centimeters of distilled
water.
28l
Method.
In a small Erlenmeyer flask or test tube, dissolve 0.2 to 0.5
gram of steel, depending on the carbon content of the sample,
in 5 to 20 cubic centimeters of the nitric acid. Boil gently
until the solution is complete and the liquid is clear. Cool and
compare with a solution of a standard steel treated under like
conditions.
NOTE.
In order to obtain reliable results by this method the standard
steel should be of the same kind, of approximately the same chemical
composition, and in the same physical condition as the sample steel.
The carbon content of the standard steel is determined by the direct
combustion method.
DETERMINATION OF MANGANESE BY THE
BISMUTHATE METHOD.
Solutions Required.
Nitric Acid. — Mix 500 cubic centimeters of nitric acid, spe-
cific gravity 1.42, and 1,500 cubic centimeters of distilled water.
Nitric Acid for Washing. — Mix 30 cubic centimeters of
nitric acid, specific gravity 1.42, and 970 cubic centimeters of
distilled water.
Stock Sodium Arsenite. — To 15 grams of arsenious acid
(As2O3) in a 300 cubic centimeter Erlenmeyer flask, add 45
grams of sodium carbonate and 150 cubic centimeters of dis-
tilled water. Heat the flask and contents on a water bath
until the arsenious acid is dissolved, cool the solution and make
up to 1,000 cubic centimeters with distilled water.
Standard Sodium Arsenite. — Dilute 300 cubic centimeters of
stock-sodium-arsenite solution to 1,000 cubic centimeters with
distilled water and titrate against potassium permanganate
solution (about N/io), which has been standardized by using
Bureau of Standards sodium oxalate.1 Adjust the solution so
that i cubic centimeter is equivalent to o.io per cent, of man-
ganese, when a i-gram sample is taken.
i Circular No. 40, Bureau of Standards, Oct. i, 1912.
282
The factor Na2C2O4 »~* Mil = 0.16397 (using the 1913
atomic weights).
Method.
In a 300 cubic centimeter Erlenmeyer flask dissolve I gram
of steel in 50 cubic centimeters of the nitric acid, and boil to
expel the oxides of nitrogen. Cool, and add about T/2 gram of
sodium bismuthate and heat for a few minutes, or until the
pink color has disappeared, with or without precipitation of
manganese dioxide. Add small portions of ferrous sulphate
(or any suitable reducing agent) in sufficient quantity to clear
the solution, and boil to expel the oxides of nitrogen. Cool to
15° C., add an excess of sodium bismuthate and agitate for a
few minutes. Add 50 cubic centimeters of 3 per cent, nitric
acid and filter through an alundum filter or asbestos pad, wash-
ing with 3 per cent, nitric acid. Titrate immediately with
standard-sodium-arsenite solution to the disappearance of the
pink color, each cubic centimeter required representing o.io
per cent, manganese.
NOTES.
In the method, the preliminary treatment with sodium bismuthate
has been found by a number of investigators to be apparently unneces-
sary; however, the available data to confirm this position are not con-
sidered sufficient to warrant its omission.
In making the asbestos filter pad it is advisable to have a thin bed,
and as much surface as possible. This insures rapid filtration, and
the filter may be used until it becomes clogged with bismuthate.
The filtrate must be perfectly clear, since the least particle of
bismuthate carried through the filter will vitiate the results.
DETERMINATION OF MANGANESE BY THE
PERSULPHATE METHOD.
(Routine.)
Solutions Required.
Nitric Acid. — Mix 1,000 cubic centimeters of nitric acid,
specific gravity 1.42, and 1,200 cubic centimeters of distilled
water.
283
Silver Nitrate. — Dissolve 1.33 grams of silver nitrate in
1,000 cubic centimeters of distilled water.
Stock Sodium Arsenite. — To 15 grams of arsenious acid
(As2O3) in a 300 cubic centimeter Erlenmeyer flask, add 45
grams of sodium carbonate and 150 cubic centimeters of dis-
tilled water. Heat the flask and contents on a water bath
until the arsenious acid is dissolved, cool the solution and make
up to 1,000 cubic centimeters with distilled water.
Standard Sodium Arsenite. — Dilute a sufficient quantity of
stock-sodium-arsenite solution with distilled water, and stand-
ardize against a steel of known manganese content, as deter-
mined by the bismuthate method. This solution should be of
such strength that each cubic centimeter will be equivalent to
o.io per cent, of manganese on the basis of the weight of
sample taken.
Method.
In a small Erlenmeyer flask or large test tube, dissolve o.i
to 0.3 gram of steel, depending on the manganese content of
the sample, in 15 cubic centimeters of the nitric acid. Boil gen-
tly until the solution is complete and the liquid is clear. Add 15
cubic centimeters silver nitrate solution and I gram of am-
monium persulphate, and continue heating the solution for
T/2 minute after the oxidation begins and bubbles rise freely.
Cool in running water and complete the determination by either
of the following procedures :
(a) C olorimetric . — Compare the color of the solution with
that of a standard steel treated under like conditions.
(b) Titration. — Titrate with standard-sodium-arsenite solu-
tion to the disappearance of the pink color, each cubic centi-
meter required representing o.io per cent, of manganese.
NOTES.
In order to obtain reliable results by the colorimetric procedure,
the standard should be of the same kind and of approximately the
same chemical composition as the sample steel. The manganese con-
tent of the standard steel is determined by the bismuthate method.
The ammonium persulphate should be kept in moistened condition
by small additions ot" distilled water at required intervals.
284
DETERMINATION OF PHOSPHORUS BY THE
MoiyYBDATE-MAGNESIA METHOD.
Solutions Required.
Nitric Acid. — Mix 1,000 cubic centimeters of nitric acid,
specific gravity 1.42, and 1,200 cubic centimeters of distilled
water.
Nitric Acid for Washing. — Mix 20 cubic centimeters nitric
acid, specific gravity 1.42, and 1,000 cubic centimeters of dis-
tilled water.
Potassium Permanganate. — Dissolve 25 grams of potassium
permanganate in 1,000 cubic centimeters of distilled water.
Ammonium Bisulphite. — Dissolve 30 grams of ammonium
bisulphite in 1,000 cubic centimeters of distilled water.
Ammonium Hydroxide, approximately 10 per cent. — Mix
1,000 cubic centimeters of ammonium hydroxide, specific grav-
ity 0.90, and 2,000 cubic centimeters of distilled water.
Ammonium Molybdate — Solution No. i. — Place in a beaker
100 grams of 85 per cent, molybdic acid, mix it thoroughly
with 240 cubic centimeters of distilled water, add 140 cubic
centimeters of ammonium hydroxide, specific gravity 0.90,
filter, and add 60 cubic centimeters of nitric acid, specific
gravity 1.42.
Solution No. 2. — Mix 400 cubic centimeters of nitric acid,
specific gravity 1.42, and 960 cubic centimeters of distilled
water.
When the solutions are cold, add solution No. I to solution
No. 2, stirring constantly; then add o.i gram of ammonium
phosphate dissolved in 10 cubic centimeters of distilled water,
and let stand at least 24 hours before using.
Magnesia Mixture. — Dissolve 50 grams of magnesium chlo-
ride and 125 grams of ammonium chloride in 750 cubic centi-
meters of distilled water, and then add 150 cubic centimeters of
ammonium hydroxide, specific gravity 0.90.
Method.
In a 300 cubic centimeter Erlenmeyer flask dissolve 5 grams
of steel in 75 cubic centimeters of the nitric acid. Heat to
boiling; while boiling add about 12 cubic centimeters of the
potassium-permanganate solution, and continue boiling until
manganese dioxide precipitates. Dissolve this precipitate by
additions of the ammonium bisulphite solution, boil until clear
and free from brown fumes, cool to 35° C., add 100 cubic
centimeters of the ammonium-molybdate solution at room tem-
perature, let stand I minute, shake or agitate for 3 minutes,
filter on a 9-centimeter paper and wash the precipitate at least
3 times with the 2 per cent, nitric-acid solution to free it from
iron.
Treat the precipitate on the filter with the 10 per cent, am-
monium-hydroxide soluion, letting the solution run into a
loo-cubic centimeter beaker containing 10 cubic centimeters of
hydrochloric acid, specific gravity 1.20, and 0.5 gram of citric
acid; add 30 cubic centimeters of ammonium hydroxide, spe-
cific gravity 0.90, cool, and then add 10 cubic centimeters of the
magnesia mixture very slowly, while stirring the solution
vigorously. Set aside in a cool place for 2 hours, filter and
wash with the 10 per cent, ammonium hydroxide solution. Ig-
nite and weigh. Dissolve the precipitate of magnesium pyro-
phosphate with 5 cubic centimeters of nitric acid, specific
gravity 1.20, and 20 cubic centimeters of distilled water, filter
and wash with hot water. Ignite and weigh. The difference
in weights represents pure magnesium pyrophosphate contain-
ing 27.84 per cent, of phosphorus.
NOTE.
The ammonium molybdate solution should be kept in a cool place
and should always be filtered before using.
DETERMINATION OF PHOSPHORUS BY THE Ai, KALI METRIC
METHOD.
(Routine.)
Solutions Required.
Nitric Acid. — Mix 1,000 cubic centimeters of nitric acid,
19
286
specific gravity 1.42, and 1,200 cubic centimeters of distilled
water.
Nitric Acid for Washing. — Mix 20 cubic centimeters of
nitric acid, specific gravity 1.42, and 1,000 cubic centimeters
of distilled water.
Potassium Permanganate. — Dissolve 25 grams of potassium
permanganate in 1,000 cubic centimeters of distilled water.
Ammonium Bisulphite. — Dissolve 30 grams of ammonium
bisulphite in 1,000 cubic centimeters of distilled water.
Ammonium Molybdate. — Solution No. i. — Place in a beaker
100 grams of 85 per cent, molybdic acid, mix it thoroughly with
240 cubic centimeters of distilled water, add 140 cubic centi-
meters of ammonium hydroxide, specific gravity 0.90, filter and
add 60 cubic centimet ers of nitric acid, specific gravity 1.42.
Solution No. 2. — Mix 400 cubic centimeters of nitric acid,
specific gravity 1.42, and 960 cubic centimeters of distilled
water.
When the solutions are cold, add solution No. I to solution
No. 2, stirring constantly; then add o.i gram of ammonium
phosphate dissolved in 10 cubic centimeters of distilled water
and let stand at least 24 hours before using.
Potassium Nitrate, I per cent. — Dissolve 10 grams of potas-
sium nitrate in 1,000 cubic centimeters of distilled water.
Phenolphthalein Indicator. — Dissolve 0.2 gram in 50 cubic
centimeters of 95 per cent, ethyl alcohol and 50 cubic centi-
meters of distilled water.
Standard Sodium Hydroxide. — Dissolve 6.5 grams of puri-
fied sodium hydroxide in 1,000 cubic centimeters of distilled
water, add a slight excess of I per cent, solution of barium
hydroxide, let stand for 24 hours, decant the liquid, and
standardize it against a steel of known phosphorus content,
as determined by the molybdate magnesia method, so that I
cubic centimeter will be equivalent to o.oi per cent, of phos-
phorus on the basis of a 2-gram sample (see notes). Protect
the solution from carbon dioxide with a soda lime tube.
Standard Nitric Acid. — Mix 10 cubic centimeters of nitric
acid, specific gravity 1.42, and 1,000 cubic centimeters of dis-
28;
tilled water. Titrate the solution against standardized sodium
hydroxide, using phenolphthalein as indicator, and make it
equivalent to the sodium hydroxide by adding distilled water.
Method.
In a 300 cubic centimeter Erlenmeyer flask dissolve 2 grams
of steel in 50 cubic centimeters of the nitric acid. Heat the
solution to boiling and while boiling add about 6 cubic centi-
meters of the potassium permanganate solution and continue
boiling until manganese dioxide precipitates. Dissolve this
precipitate by addition of the ammonium bisulphite solution,
boil until clear and free from brown fumes, cool to 80° C.,
add 50 cubic centimeters of the ammonium molybdate solu-
tion at room temperature, let stand I minute, shake or agitate
for 3 minutes, and filter on a 9 centimeter paper. Wash
the precipitate three times with the 2 per cent, nitric acid solu-
tion to free it from iron, and continue the washing with the I
per cent potassium nitrate solution until the precipitate and
flask are free from acid.
Transfer the paper and precipitate to a solution flask, add
20 cubic centimeters of distilled water, 5 drops of phenol-
phthalein solution as indicator, and an excess of standard
sodium hydroxide solution. Insert a rubber stopper and shake
vigorously until solution of the precipitate is complete. Wash
off the stopper with distilled water and determine the excess
of sodium hydroxide solution by titrating with standard nitric
acid solution. Each cubic centimeter of standard sodium hy-
droxide solution represents o.oi per cent, of phosphorus.
NOTES.
The ammonium molybdate solution should be kept in a cool place
and should always be filtered before using.
All distilled water used in titration should be freed from carbon
dioxide by boiling or otherwise.
Bureau of Standards Standard Steel No. 19 (a) is recommended
as a suitable steel for standardization of the sodium hydroxide solution.
288
DETERMINATION OF SULPHUR BY THE; OXIDATION METHOD.
Solution Required.
Barium Chloride. — Dissolve 100 grams of barium chloride
in 1,000 cubic centimeters of distilled water.
Method.
In a 400 cubic centimeter beaker dissolve 5 grams of the
steel in a mixture of 40 cubic centimeters of nitric acid, spe-
cific gravity 1.42, and 5 cubic centimeters of hydrochloric acid,
specific gravity 1.20, add 0.5 gram of sodium carbonate and
evaporate the solution to dryness. Add 40 cubic centimeters
of hydrochloric acid, specific gravity 1.20, evaporate to dry-
ness and bake at a moderate heat. After solution of the resi-
due in 30 cubic centimeters of hydrochloric acid, specific grav-
ity i. 20, and evaporation to sirupy consistency, add 2 to 4
cubic centimeters of hydrochloric acid, specific gravity 1.20,
and then 30 to 40 cubic centimeters of hot water. Filter and
wash with cold water, the final volume not exceeding 100
cubic centimeters. To the cold filtrate add 10 cubic centi-
meters of the barium chloride solution. I^et stand at least 24
hours, filter on a 9 centimeter paper, wash the precipi-
tate first with a hot solution containing 10 cubic centimeters
of hydrochloric acid, specific gravity 1.20, and I gram barium
chloride to the liter, until free from iron; and then with hot
water till free from chloride. Ignite and weigh as barium
sulphate.
Keep the washings separate from the main filtrate and
evaporate them to recover any dissolved barium sulphate.
NOTE.
A blank determination on all reagents used should be made and
the results corrected accordingly.
DETERMINATION OF SULPHUR BY THE EVOUJTION-TITRATION
METHOD.
(Routine.)
Apparatus.
Use a 480 cubic centimeter flask with a delivery tube and a
300 cubic centimeter tumbler of tall form (Fig. 71).
289
Capacity
IB 02.
1
1
1
1
1 w ,
c c.
^^^
Ir^F "^
1 ~
~r
r^r "i
t-
i
—
L_
\ V
FIG. 71 . —Apparatus for Determination of Sulphur by the Evolution Method.
Solutions Required.
Dilute Hydrochloric Acid. — Mix 500 cubic centimeters of
hydrochloric acid, specific gravity 1.20, and 500 cubic centi-
meters of distilled water.
Ammoniacal Cadmium Chloride. — Dissolve 10 grams of
cadmium chloride in 400 cubic centimeters of distilled water
and add 600 cubic centimeters of ammonium hydroxide, spe-
cific gravity 0.90.
Potassium lodate. — Dissolve 1.116 grams of potassium
iodate and 12 grams of potassium iodide in 1,000 cubic centi-
meters of distilled water. Standardize with a steel of known
sulphur content. Each cubic centimeter should be equivalent
to o.oi per cent, of sulphur, when a 5 gram sample is used
(see notes).
290
Starch. — To 1,000 cubic centimeters of boiling distilled
water, add a cold suspension of 6 grams of starch in 100
cubic centimeters of distilled water; cool, add a solution of
6 grams of zinc chloride in 50 cubic centimeters of distilled
water, and mix thoroughly.
Method.
Place 5 grams of steel in the flask and connect the latter as
shown in Fig. 62. Place 10 cubic centimeters of the ammoniacal
FIG. 72.
cadmium chloride solution and 150 cubic centimeters of dis-
tilled water in the tumbler. Add 80 cubic centimeters of the
dilute hydrochloric acid to the flask through the thistle tube,
heat the flask with its contents gently until the solution of the
steel is complete, then boil the solution for y2 minute. Re-
move the tumbler which contains all the sulphur as cadmium
sulphide, and to it add 5 cubic centimeters of starch solution
and 40 cubic centimeters of the dilute hydrochloric acid, ti-
trating immediately with potassium iodate solution to a per-
manent blue color.
NOTES.
Extremely slow or rapid evolution of hydrogen sulphide is to be
avoided.
Bureau of Standards Standard Steel No. 8 (a) is recommended
for standardizing the potassium iodiate solution.
vS />
FIG. 73.
Editor's Note. — Another very convenient apparatus is shown in
Figs. 72 and 73. It can be heated without getting the cadmium chloride
solution hot while heating the flask containing the steel. In using this
292
form, 10 cubic centimeters of the cadmium solution are drawn into
the tube, Fig. 73, without diluting.
After all the H2S has been driven over, the tube is disconnected
and emptied into a 600 cubic centimeter beaker by pouring it out
through a. The tube is then washed by filling it up first with water,
then with dilute hydrochloric acid, and again with water. This is
best accomplished by holding the nozzle of a wash bottle against b and
blowing until the water or acid reaches the top of the tube. Remove
wash bottle and empty the tube into beaker as above.
DETERMINATION OF SILICON BY THE NITRO-SULPHURIC
METHOD.
Solutions Required.
Nitro-Sulphuric Acid. — Mix 1,000 cubic centimeters of sul-
phuric acid, specific gravity 1.84, 1,500 cubic centimeters of
nitric acid, specific gravity 1.42, and 5,500 cubic centimeters
of distilled water.
Dilute Hydrochloric Acid. — Mix 100 cubic centimeters of
hydrochloric acid, specific gravity 1.20, and 900 cubic centi-
meters of distilled water.
Method.
Add cautiously 80 cubic centimeters of the nitro-sulphuric
acid to 4.702 grams of steel, in a platinum or porcelain dish
of 300 cubic centimeters capacity, cover with a watch glass,
heat until the steel is dissolved and evaporate slowly until
copious fumes of sulphuric acid are evolved. Cool, add 125
cubic centimeters of distilled water, heat with frequent stirring
until all salts are dissolved, add 5 cubic centimeters of hydro-
chloric acid, specific gravity 1.20, heat for 2 minutes, and
filter on a 9 centimeter paper. Wash the precipitate several
times with hot water, then with hydrochloric acid and hot
water alternately to complete the removal of iron salts,
and finally with hot water until free from acid. .Transfer the
filter to a platinum crucible, burn off the paper carefully with
the crucible covered, finally igniting over a blast lamp or in a
muffle furnace at 1,000° C. for at least 20 minutes; cool in a
293
desiccator and weigh. Add sufficient sulphuric acid, specific
gravity 1.84, to moisten the silica and then a small amount of
hydrofluoric acid. Evaporate to dryness, ignite arid weigh.
The difference in weights in milligrams divided by 100 equals
the percentage of silicon.
NOTE.
A blank determination on all reagents used should be made and
the results corrected accordingly.
DETERMINATION OF SILICON BY THE SULPHURIC ACID
METHOD.
(Optional.)
Solution Required.
Dilute Hydrochloric Acid. — Mix 100 cubic centimeters of
hydrochloric acid, specific gravity 1.20, and 900 cubic centi-
meters of distilled water.
Method.
To 2.351 grams of steel, in a beaker of low form of 500
cubic centimeters capacity, add 60 cubic centimeters of dis-
tilled water, and then cautiously 15 cubic centimeters of sul-
phuric acid, specific gravity 1.84. Cover with a watch glass,
heat until the steel is dissolved and evaporate until copious
fumes of sulphuric acid are evolved. Cool, add 100 cubic
centimeters of distilled water and heat with frequent stirring
until the salts are in solution. Filter on a 9 centimeter paper,
wash the precipitate several times with cold water, then with
cold dilute hydrochloric acid until free from iron, and finally
with cold water until free from acid. Ignite and weigh. Add
sufficient sulphuric acid, specific gravity 1.84, to moisten the
silica and then a small amount of hydrofluoric acid. Evapo-
rate to dryness, ignite and weigh. The difference in weights
in milligrams divided by 50 equals the percentage of silicon.
NOTE.
A blank determination on all reagents used should be made and
the results corrected accordingly.
294
DETERMINATION OF COPPER.
Solutions Required.
Sulphuric Acid. — Mix 200 cubic centimeters of sulphuric
acid specific gravity X 1.84, and 800 cubic centimeters of
distilled water.
Potassium Ferrocyanide. — Dissolve 10 grams of potassium
ferrocyanide in 100 cubic centimeters of distilled water.
Standard Copper Nitrate. — Dissolve 2 grams of purest elec-
trolytic copper in 20 cubic centimeters of nitric acid (i : i),
and dilute to 1,000 cubic centimeters with distilled water.
Each cubic centimeter is equivalent to 0.02 per cent, of copper
on the basis of a 10 gram sample.
Method.
In a 300 cubic centimeter beaker dissolve 10 grams of the
steel in 75 cubic centimeters of the sulphuric acid, and then
add 150 cubic centimeters of distilled water. Heat the solu-
tion and saturate with hydrogen sulphide, filter and wash the
precipitate free from iron with i per cent, sulphuric acid con-
taining hydrogen sulphide. Incinerate the paper with its con-
tents in a porcelain crucible and fuse with 0.5 gram of acid
sodium sulphate. Extract with hot water, filter, and complete
the determination colorimetrically as under i(a) or i(&), or
electrolytically as under 2, as follows :
i. Evaporate the filtrate to about 25 cubic centimeters, make
faintly ammoniacal, filter into a 100 cubic centimeter Nessler
tube and wash with hot water.
(a) If the solution is a strong blue, to another 100 cubic
centimeter Nessler tube add 50 cubic centimeters of distilled
water, 5 cubic centimeters of ammonium hydroxide, specific
gravity 0.90, and from a burette the standard copper nitrate
solution until the blue colors match.
(b) If the solution is a faint blue, to the filtrate in a Nessler
tube add the dilute sulphuric acid to faint acidity and then
a few drops of the potassium ferrocyanide solution. To an-
other 100 cubic centimeter Nessler tube add 50 cubic centi-
295
meters of distilled water, a few drops of the potassium ferro-
cyanide solution, and from a burette the standard copper ni-
trate solution until the reddish brown colors match.
2. Make the nitrate slightly acid with sulphuric acid, dilute
with distilled water to a suitable volume, and determine the
copper electrolytically.
DETERMINATION OF NICKEL BY THE GRAVIMETRIC DIMETHYI/-
GLYOXIME METHOD.
Solutions Required.
Hydrochloric Acid. — Mix 500 cubic centimeters of hydro-
chloric acid, specific gravity, 1.20, and 500 cubic centimeters
of distilled water.
Dimethylglyoxime. — Dissolve I gram of dimethylglyoxime
in 100 cubic centimeters of 95 per cent, ethyl alcohol.
Method.
In a 150 cubic centimeter beaker dissolve I gram of the
steel in 20 cubic centimeters of the hydrochloric acid, and
add about 2 cubic centimeters of nitric acid, specific gravity
1.42, to oxidize the iron. Filter the solution and add to the
filtrate 6 grams of tartaric acid, and water till the volume is
300 cubic centimeters. Make the solution faintly ammoniacal,
then faintly acid with the hydrochloric acid and heat nearly
to boiling; add 20 cubic centimeters of the dimethylglyoxime
solution and then ammonium hydroxide, specific gravity 0.90,
drop by drop till faintly alkaline, stirring vigorously. After
standing i hour, filter on a weighed Gooch crucible, wash with
hot water, dry at 110° to 120° C. and weigh. The precipitate
contains 20.31 per cent, of nickel.
NOTES.
In making dimethylglyoxime solution, methyl alcohol may be sub-
stituted for ethyl alcohol.
The weight of sample taken should be varied according to the
nickel content.
296
DETERMINATION OF NlCKEX BY THE VOLUMETRIC DlMETHYI,-
METHOD.
(Routine.)
Solutions Required.
Hydrochloric Acid. — Mix 500 cubic centimeters of hydro-
chloric acid, specific gravity 1.20, and 500 cubic centimeters
of distilled water.
Dimethylglyoxime. — Dissolve I gram of dimethylglyoxime
in 100 cubic centimeters of 95 per cent, ethyl alcohol.
Silver Nitrate. — Dissolve 0.5 gram of silver nitrate in 1,000
cubic centimeters of distilled water.
Potassium Iodide. — Dissolve 20 grams of potassium iodide
in 100 cubic centimeters of distilled water.
Standard Potassium Cyanide. — Dissolve 2.29 grams of potas-
sium cyanide in 1,000 cubic centimeters of distilled water.
Standardize this solution by the procedure described below,
against a steel of known nickel content as determined by the
gravimetric dimethylglyoxime method, so that each cubic centi-
meter is equivalent to 0.05 per cent, of nickel on the basis of
a i -gram sample (see notes).
Method.
In a 150 cubic centimeter beaker dissolve I gram of the
steel in 20 cubic centimeters of the hydrochloric acid, and add
about 2 cubic centimeters of nitric acid, specific gravity 1.42,
to oxidize the iron. Filter the solution and add to the fil-
trate 6 grams of tartaric acid, and water until the volume is
300 cubic centimeters. Make the solution faintly ammoniacal,
then faintly acid with the hydrochloric acid, and cool thor-
oughly. Add 20 cubic centimeters of the dimethylglyoxime
solution and then ammonium hydroxide, specific gravity 0.90,
drop by drop, till faintly alkaline, stirring vigorously. After
standing for a few minutes, filter on a Gooch crucible arid
wash with hot water. Dissolve the precipitate on the filter
with 10 to 20 cubic centimeters of nitric acid (hot), specific
297
gravity 1.42, added drop by drop, and then wash 5 times with
hot water, using suction. To the solution in a 500 cubic centi-
meter beaker add 3 grams of ammonium persulphate and boil
for 5 minutes. Cool, make distinctly ammoniacal, add 10
cubic centimeters each of the silver nitrate and potassium
iodide solutions, and titrate with the standard potassium cy-
anide solution to a faint turbidity.
NOTES.
In making dimethylglyoxime solution, methyl alcohol may be sub-
stituted for ethyl alcohol.
Bureau of Standards Standard Steel No. 33 is recommended for
standardizing the potassium cyanide solution.
The weight of sample taken should be varied according to the
nickel content.
DETERMINATION OF CHROMIUM.
Solutions Required.
Hydrochloric Acid. — Mix 500 cubic centimeters of hydro-
chloric acid, specific gravity 1.20, and 500 cubic centimeters
of distilled water.
Sodium Carbonate. — A saturated solution; approximately
60 grams of sodium carbonate and 100 cubic centimeters of
distilled water.
Barium Carbonate. — Ten grams of finely divided " barium
carbonate suspended in 100 cubic centimeters of distilled
water.
Standard Sodium Chromate. — Dissolve 2.6322 grams of
sodium chromate in 1,000 cubic centimeters of distilled water.
Each cubic centimeter is equivalent to 0.02 per cent, chro-
mium, when a 5-gram sample is used.
Standard Potassium Permanganate. — Dissolve 2 grams of
potassium permanganate in 1,000 cubic centimeters of dis-
tilled water. Standardize by using Bureau of Standards so-
dium oxalate,1 and dilute the solution with distilled water so
that i cubic centimeter is equivalent to 0.02 per cent, chro-
mium, when a 5-gram sample is taken.
1 Circular No. 40, Bureau of Standards, Oct. i, 1912.
298
The factor Na2C2O4 »-* Cr = 0.2584 (using the 1913 atomic
weights).
Ferrous Sulphate. — Dissolve 25 grams of ferrous ammoni-
um sulphate in 900 cubic centimeters of distilled water and
100 cubic centimeters of sulphuric acid ( I : I ) .
Method.
In a 300 cubic centimeter Erlenmeyer flask, covered, dis-
solve 5 grams of steel in 50 cubic centimeters of the hydro-
chloric acid. When completely dissolved, and gradually the
saturated solution of sodium carbonate until practically all the
free acid is neutralized; finish the neutralization with the ba-
rium carbonate suspension, using an excess of about I gram
of the carbonate. Boil the solution in the flask for 10 or 15
minutes, with the cover on. Filter the precipitate rapidly on
paper and wash twice with hot water. Transfer the filter to
a platinum crucible and after burning off the paper, fuse the
residue for 10 minutes with a mixture of 5 grams of sodium
carbonate and 0.25 gram of potassium nitrate. Dissolve the
fusion in water, transfer to a beaker, add 2 cubic centimeters
of 3 per cent, hydrogen peroxide, boil a few minutes and
filter. Complete the determination of chromium in the filtrate
by either of the following procedures:
1. If the solution is a strong yellow, add 10 cubic centi-
meters of sulphuric acid (i : i), and then the ferrous sulphate
solution in measured excess. Cool thoroughly and titrate
with the standard potassium permanganate solution. The
number of cubic centimeters of the potassium permanganate
solution obtained, subtracted from the number corresponding
to the volume of the ferrous sulphate solution used, will give
the volume of the potassium permanganate solution equivalent
to the chromium in the sample.
2. If the solution is a light yellow, cool the 'solution and
transfer to a 100 cubic centimeter Nessler tube. To another
Nessler tube add distilled water, and from a burette add the
standard sodium chromate solution until the yellow colors
match.
299
NOTE.
If procedure No. I is used, all hydrogen peroxide must be
destroyed by boiling before acidifying, otherwise chromic acid will be
reduced at this stage.
CHEMICAL ANALYSIS OF ALLOY STEELS AS PUBLISHED BY THE
AMERICAN SOCIETY FOR TESTING MATERIALS.
ADOPTED, 1915.
NICKEL STEEL.
Determination of Carbon.
See the Determination of Carbon in Plain Carbon Steel by
the Direct-Combustion Method.1
Determination of Manganese.
See the Determination of Manganese in Plain Carbon Steel
by the Bismuthate Method.1
See the Determination of Manganese in Plain Carbon Steel
by the Persulphate Method (Routine).
Determination of Phosphorus.
See the Determination of Phosphorus in Plain Carbon Steel
by the Molybdate Magnesia Method.1
See the Determination of Phosphorus in Plain Carbon Steel
by the Alkalimetric Method (Routine).1
Determination of Sulphur.
See the Determination of Sulphur in Plain Carbon Steel by
the Oxidation Method.1
See the Determination of Sulphur in Plain Carbon Steel by
the Evolution-Titration Method (Routine).1
NOTES.
The Evolution-Titration Method should not be used with steels
containing appreciable amounts of tungsten, or of copper or other
metals precipitated by hydrogen sulphide from acid solutions.
The annealing of the steel drillings has been found by a number
of investigators to increase the degree of refinement of the method.
1 Standard Methods for Chemical Analysis of Plain Carbon Steel (Serial Designa-
tion: A 33), 1915 Year-Book, p. 201.
300
Determination of Silicon.
See the Determination of Silicon in Plain Carbon Steel by
the Nitro-Sulphuric Method.1
See the Determination of Silicon in Plain Carbon Steel by
the Sulphuric Acid Method (Optional).1
Determination of Nickel.
See the Determination of Nickel in Plain Carbon Steel by
the Gravimetric Dimethylglyoxime Method.1
See the Determination of Nickel in Plain Carbon Steel by
the Volumetric Dimethylglyoxime Method (Routine).1
Determination of Nickel by the Ether Extraction-Cyanide
Titratio n Meth o d .
(Optional Routine.)
SOLUTIONS REQUIRED.
Hydrochloric Acid. — Mix 600 cubic centimeters of hydro-
chloric acid, specific gravity 1.20, and 400 cubic centimeters of
distilled water.
Nitric Acid. — Mix 1,000 cubic centimeters of nitric acid,
specific gravity 1.42, and 1.200 cubic centimeters of distilled
water.
Potassium Iodide. — Dissolve 20 grams of potassium iodide
in 1,000 cubic centimeters of distilled water.
Silver Nitrate. — Dissolve 0.5 gram of silver nitrate in 1,000
cubic centimeters of distilled water.
Standard Potassium Cyanide. — Dissolve 4.589 grams of
potassium cyanide in 1,000 cubic centimeters of distilled water.
Standardize the solution by the procedure described below,
against a steel of known nickel content as determined by the
gravimetric-dimethylglyoxime method, so that I cubic centi-
meter is equivalent to o.io per cent, nickel on the basis of a
i -gram sample (see note).
1 Standard Methods for Chemical Analysis of Plain Carbon Steel (Serial Designa-
tion: A 33), 1915 Year-Book, p. 201.
3oi
METHOD.
In a 150 cubic centimeter beaker dissolve i gram of the steel
in 20 cubic centimeters of the hydrochloric acid, add about
2 cubic centimeters of nitric acid, specific gravity 1.42, to
oxidize the iron, and boil to expel the oxides of nitrogen.
Cool, and transfer the solution into an 8-ounce separatory
funnel, rinsing the beaker with small portions of the hydro-
chloric acid. Add 50 cubic centimeters of ether, shake for 5
minutes, let settle for I minute, and then draw off lower clear
solution into another 8-ounce separatory funnel. Add 10
cubic centimeters of hydrochloric acid, specific gravity 1.20, to
the solution in the first separatory funnel, cool, shake thor-
oughly, allow to settle for I minute, and then draw off the
lower clear solution into the second separatory funnel. To
the combined solutions in the second separatory funnel add
50 cubic centimeters of ether, shake for 5 minutes, let settle for
i minute, and then draw off the clear layer into a 150 cubic
centimeter beaker. Heat the aqueous solution gently to expel
the ether, add 0.2 gram of potassium chlorate, boil until
chlorate is decomposed, dilute to 100 cubic centimeters with
hot water, make faintly ammoniacal, and boil for 5 minutes.
Filter and wash with hot water. To the filtrate add 10 cubic
centimeters of hydrochloric acid, specific gravity 1.20, heat just
short of boiling and precipitate the copper with hydrogen sul-
phide. Filter and wash with hot water. Boil the filtrate to
expel hydrogen sulphide, reducing the volume by evaporation
to approximately 100 cubic centimeters, cool, and make solu-
tion distinctly ammoniacal, add 10 cubic centimeters each of
the silver-nitrate and potassium-iodide solutions, and titrate
with the standard potassium-cyanide solution to a clear solu-
tion.
NOTE.
Bureau of Standards Standard Steel No. 33 is recommended for
standardizing the potassium cyanide solution.
20
302
Determination of Carbon.
See the Determination of Carbon by the Direct-Combustion
Method.1
Determination of Manganese by the Zinc Oxlde-
Bismuthate Method.
SOLUTIONS REQUIRED.
Sulphuric Acid. — Mix 200 cubic centimeters of sulphuric
acid, specific gravity 1.84, and 800 cubic centimeters of dis-
tilled water.
Nitric Acid. — Mix 500 cubic centimeters of nitric acid,
specific gravity 1.42 and 1,500 cubic centimeters of distilled
water.
Nitric Acid for Washing. — Mix 30 cubic centimeters of
nitric acid, specific gravity 1.42, and 970 cubic centimeters of
distilled water.
Sodium Carbonate. — A saturated solution; approximately
60 grams of sodium carbonate and 100 cubic centimeters of
distilled water.
Zinc Oxide. — Twenty grams of zinc oxide (dry process)
suspended in 100 cubic centimeters of distilled water (see
notes).
Stock Sodium Arsenite. — To 15 grams of arsenious oxide
(As2O3) in a 300 cubic centimeter Erlenmeyer flask, add 45
grams of sodium carbonate and 150 cubic centimeters of dis-
tilled water. Heat the flask and contents on a water bath until
the arsenious oxide is dissolved, cool the solution and make up
to 1,000 cubic centimeters with distilled water.
Standard Sodium- Arsenite. — Dilute 300 cubic centimeters of
the stock-sodium-arsenite solution to 1,000 cubic centimeters
with distilled water and titrate against potassium-permangan-
ate solution (about N/io) which has been standardized by
1 Standard Methods for Chemical Analysis of Plain Carbon Steel (Serial Designa-
tion: A 33), 1915 Year-Book, p. 201.
303
using Bureau of Standards sodium oxalate.1 Adjust the solu-
tion so that I cubic centimeter is equivalent to o.io per cent, of
manganese on the basis of a i-gram sample.
The factor Na2C2O4 — > Mn == 0.16397 (using the 1913
atomic weights).
METHOD.
In a platinum or porcelain dish of 300 cubic centimeters
capacity, to 2.5 grams of the steel add 40 cubic centimeters of
the sulphuric acid, cover with a watch glass, and heat until
the steel is dissolved. Add about 4 cubic centimeters of nitric
acid, specific gravity 1.42, to oxidize the iron and evaporate
slowly until copious fumes of sulphuric acid are evolved.
Cool, add 100 cubic centimeters of hot water, heat with fre-
quent stirring until all salts are dissolved, then transfer the
solution into a volumetric 500 cubic centimeter flask. Add the
sodium-carbonate solution until near neutrality, and the pre-
cipitate formed dissolves with difficulty, then add small por-
tions of the zinc-oxide suspension, shaking vigorously after
each addition, until after settling of the coagulated precipitate,
the supernatant liquid is practically clear. Cool, and make
up to the mark with water. Mix thoroughly by pouring the
entire contents of the flask into a large, dry beaker, and back
again to the flask, repeating several times. Allow the pre-
cipitate to settle, filter off 200 cubic centimeters of the solution
into a 300 cubic centimeter Erlenmeyer flask, add 25 cubic
centimeters of the nitric acid solution, and boil to expel the
oxides of nitrogen. Cool, add 0.5 gram of sodium bismuthate
and heat for a few minutes, or until the pink color has disap-
peared, with or without the precipitation of manganese dioxide.
Add small portions of ferrous sulphate (or other suitable re-
ducing agent) in sufficient quantity to clear the solution, and
boil to expel the oxides of nitrogen. Cool to 15° C., add an
excess of sodium bismuthate and agitate for a few minutes.
Let settle and filter through an alundum filter or asbestos pad,
washing with the 3 per cent, nitric acid. Titrate immediately
1 Circular No . 40 , Bureau of Standards, Oct. i, 1912.
304
*
with the standard sodium-arsenite solution to the disappear-
ance of the pink color.
NOTES.
In the method, the preliminary treatment with sodium bismuthate
has been found by a number of investigators to be apparently unneces-
sary ; however, the available data to confirm this position are not con-
sidered sufficient to warrant its omission.
In making the asbestos filter pad it is advisable to have a thin bed
and as much surface as possible. This insures rapid filtration and the
filter may be used until it becomes clogged with bismuthate.
The filtrate must be perfectly clear since the least particle of
bismuthate carried through the filter will vitiate the results.
The zinc-oxide reagent should be free from manganese, or a cor-
rection applied if it is present.
Determination of Manganese by the Modified
Bismuthate Method.
(Routine.)
SOLUTIONS REQUIRED.
Nitric Acid. — Mix 500 cubic centimeters of nitric acid,
specific gravity 1.42, and 1,500 cubic centimeters of distilled
water.
Nitric Acid for Washing. — Mix 30 cubic centimeters of
nitric acid, specific gravity 1.42, and 970 cubic centimeters of
distilled water.
Stock Sodium Arsenite.—To 15 grams of arsenious oxide
(As2O3) in a 300 cubic centimeter Erlenmeyer flask, add 45
grams of sodium carbonate and 150 cubic centimeters of dis-
tilled water. Heat the flask and contents on a water bath until
the arsenious oxide is dissolved, cool the solution and make up
to 1,000 cubic centimeters with distilled water.
Standard Sodium Arsenite. — Dilute 300 cubic centimeters of
the stock-sodium-arsenite solution to 1,000 cubic centimeters
with distilled water and titrate against potassium-permangan-
ate solution (about N/io) which has been standardized by
using Bureau of Standards sodium oxalate.1 Adjust the solu-
i Circular No. 40, Bureau of Standards, Oct. i 1912.
305
tion so that i cubic centimeter is equivalent to o.io per cent, of
manganese on the basis of a i-gram sample.
The factor Na2C2O4 - > Mn == 0.16397 (using the 1913
atomic weights).
METHOD.
In a 300 cubic centimeter Erlenmeyer flask dissolve I gram
of the steel in 50 cubic centimeters of the nitric acid, and boil
to expel the oxides of nitrogen. Cool to 60-70° C., add about
0.5 gram of sodium bismuthate, and heat for a few minutes,
or until the pink color has disappeared, with or without the
precipitation of manganese dioxide. Add sufficient sulphurous
acid or sodium sulphite to clear the solution and to reduce
all of the chromic acid. Cool to approximately o° C. in ice
water, add an excess of sodium bismuthate and agitate. After
30 seconds standing, filter rapidly through an alundum filter
or asbestos pad, washing with 3 per cent, nitric acid previously
cooled in ice water to approximately o° C. Titrate immedi-
ately with the standard sodium-arsenite solution to the disap-
pearance of the pink color.
NOTES.
In the method, the preliminary treatment with sodium bismuthate
has been found by a number of investigators to be apparently unneces-
sary; however, the available data to confirm this position are not
sufficient to warrant its omission.
In making the asbestos filter pad it is advisable to have a thin
bed, and as much surface as possible. This insures rapid filtration,
and the filter may be used until it becomes clogged with bismuthate.
The filtrate must be ice cold and perfectly clear, since any appre-
ciable rise of temperature above o° C., or the least particle of bis-
muthate carried through the filter will vitiate the results.
See the Determination of Manganese in Plain Carbon Steel
by the Persulphate Method.1
NOTE.
In making the titration special care should be given to standard-
izing the end-point reading, and the reading should be corrected by a
blank, which varies with the amount of chromium present.
1 Standard Methods for Chemical Analysis of Plain Carbon Steel (Serial Designa-
tion: A 33), 1915 Year-Book, p. 201.
3°6
Determination of Phosphorus.
See the Determination of Phosphorus in Plain Carbon Steel
by the Molybdate-Magnesia Method.1
See the Determination of Phosphorus in Plain Carbon Steel
by the Alkalimetric Method.1
Determination of Sulphur.
See the Determination of Sulphur in Plain Carbon Steel by
the Oxidation Method.1
See the Determination of Sulphur in Plain Carbon Steel by
the Evolution-Titration Method (Routine).1
NOTES.
The Evolution-Titration Method should not be used with steels
containing appreciable amounts of tungsten, or of copper or other
metals precipitated by hydrogen sulphide from acid solutions.
The annealing of the steel drillings has been found by a number
of investigators to increase the degree of refinement of the method.
Determination of Silicon.
See the Determination of Silicon in Plain Carbon Steel by
the Nitro-Sulphuric Method.1
See the Determination of Silicon in Plain Carbon Steel by
the Sulphuric Acid Method (Optional).1
Determination of Chromium by the Fusion Method.
SOLUTIONS REQUIRED.
Sulphuric Acid. — Mix 1,000 cubic centimeters of sulphuric
acid, specific gravity 1.84, and 3,000 cubic centimeters of dis-
tilled water.
Sodium Carbonate. — A saturated solution; approximately
60 grams of sodium carbonate and 100 cubic centimeters of
distilled water.
Magnesium Carbonate. — Ten grams of finely divided mag-
nesium carbonate suspended in 100 cubic centimeters of dis-
tilled water.
Barium Carbonate. — Ten grams of finely divided barium
carbonate suspended in 100 cubic centimeters of distilled water.
307
Nitric Acid. — Mix 1,000 cubic centimeters of nitric acid,
specific gravity 1.42, and 1,200 cubic centimeters of distilled
water.
Potassium-Ferricyanide Indicator. — Dissolve o.i gram of
potassium ferricyanide in 50 cubic centimeters of distilled
water (see notes).
Standard Potassium Bichromate. — Dissolve 5 grams of po-
tassium bichromate in 1,000 cubic centimeters of distilled
water, standardize against pure ferrous ammonium sulphate,
and adjust to tenth-normal.
Ferrous Sulphate. — Dissolve 25 grams of ferrous ammonium
sulphate in 900 cubic centimeters of distilled water and 100
cubic centimeters of sulphuric acid (i : i).
METHOD.
In a 300 cubic centimeter Erlenmeyer flask, covered, dissolve
i gram of the steel in 50 cubic centimeters of the sulphuric acid
(see notes). When completely dissolved, add 50 to 75 cubic
centimeters of hot water, then gradually the sodium-carbonate
solution until near neutrality, then add an excess of the mag-
nesium-carbonate suspension (see notes), and boil vigorously
for 15 minutes, with the cover on, adding fresh portions of the
carbonate suspension during this time, so that there is present
in the solution at the end of the operation an excess of 2 to
3 grams of the carbonate. Let settle and pour the supernatant
liquid on a rapid filter, washing by decantation twice with cold
water, pouring the washings through the filter. Transfer the
filter to a platinum crucible and after burning off the paper,
fuse the residue for 10 minutes with a mixture of 5 grams of
sodium carbonate and 0.25 gram of potassium nitrate. Dis-
solve the fusion in water, transfer to a beaker, add 2 cubic
centimeters of 3 per cent, hydrogen peroxide, boil a few
minutes and filter. Add 20 cubic centimeters of the sulphuric
acid, stir vigorously, cool and titrate against the standardized
ferrous-sulphate solution, using the potassium-ferricyanide
solution as outside indicator, or add at once a measured amount
(in excess) of the ferrous-sulphate solution, and titrate back
3o8
against the potassium-bichromate solution, using the same in-
dicator.
NOTES.
The solution of the steel may be in hydrochloric acid, specific
gravity 1.20 or any other desired strength, adjusting the amount of
acid used to avoid a large excess being present.
Barium carbonate suspension may be substituted for the mag-
nesium carbonate suspension when hydrochloric acid is used as solvent.
All hydrogen peroxide must be destroyed by boiling before acidi-
fying, otherwise chromic acid will be reduced at this stage.
The insoluble residue remaining after extraction of the fusion
should be examined for chromium.
The potassium ferricyanide indicator should be prepared fresh on
the day it is used.
The ferrous sulphate solution should be standardized on the day
it is used.
In titrating with the ferrous sulphate solution it is convenient to
divide the solution, roughly titrate one portion, add the other and finish
carefully.
Determination of Chromium by the Chlorate Method.
(Routine.) '
SOLUTIONS REQUIRED.
Nitric Acid. — Mix 1,000 cubic centimeters of nitric acid,
specific gravity 1.42, and 1,200 cubic centimeters of distilled
water.
Potassium-Ferricyanide Indicator. — Dissolve o.i gram of
potassium ferricyanide in 50 cubic centimeters of distilled
water (see notes).
Standard Potassium Bichromate.— Dissolve 5 grams of po-
tassium bichromate in 1,000 cubic centimeters of distilled
water, and standardize against pure ferrous ammonium sul-
phate, and adjust to tenth-normal.
Standard Potassium Permanganate. — Dissolve 2 grams of
potassium permanganate in 1,000 cubic centimeters of distilled
water. Standardize by using Bureau of Standards sodium
oxalate.1 Adjust the solution so that I cubic centimeter is
equivalent to o.io per cent, chromium on the basis of a i-gram
1 Circular No. 40, Bureau of Standards, Oct. i, 1912.
309
sample. The factor Na2C2O4 > Cr — 0.2584 (using the 1913
atomic weights).
Ferrous Sulphate. — Dissolve 25 grams of ferrous ammonium
sulphate in 900 cubic centimeters of distilled water and 100
cubic centimeters of sulphuric acid (i : i).
METHOD.
In a 300 cubic centimeter Erlenmeyer flask dissolve I gram
of the steel in 30 cubic centimeters of the nitric acid, and
evaporate rapidly to approximately one-half volume. Add 50
cubic centimeters of nitric acid, specific gravity 1.42, and add
i gram of sodium chlorate (see notes). Evaporate to boiling
to approximately one-half volume and complete the determina-
tion by either of the following procedures :
1. Dilute the solution with 100 cubic centimeters of distilled
water and filter off the manganese dioxide, using suction, wash-
ing with hot water. Cool the filtrate, dilute with cold water to
600 cubic centimeter volume, and titrate against the standard
ferrous-sulphate solution, using the potassium-ferricyanide
solution as outside indicator, or add at once a measured
amount (in excess) of the ferrous-sulphate solution and titrate
back against the standard potassium-bichromate solution, using
the same indicator.
2. Add 10 cubic centimeters of hydrochloric acid (i : i) and
boil until the solution is clear and all manganese dioxide dis-
solved. Cool, dilute the solution with water to 300 cubic centi-
meter volume, add the ferrous-sulphate solution in measured
amount (in excess), and titrate back with the standard po-
tassium-permanganate solution to a permanent pink color.
NOTES.
The potassium-ferricyanide indicator should be prepared fresh on
the day it is used.
The ferrous-sulphate solution should be compared on the day it is
used, with the standard potassium-permanganete or standard potas-
sium-bichromate solutions.
Potassium chlorate may be used as oxidizing agent in the place
of sodium chlorate.
In titrating with the ferrous-sulphate solution it is convenient to
divide the solution, roughly titrate one portion, add the other and
finish carefully.
3io
. Determination of Chromium by the Permanganate
Oxidation Method.
(Optional Routine.)
SOLUTIONS REQUIRED.
Sulphuric Add. — Mix 1,000 cubic centimeters of sulphuric
acid, specific gravity 1.84, and 3,000 cubic centimeters of dis-
tilled water.
Nitric Acid. — Mix 1,000 cubic centimeters of nitric acid,
specific gravity 1.42, and 1,200 cubic centimeters of distilled
water.
Potassium Permanganate. — Dissolve 25 grams of potassium
permanganate in 1,000 cubic centimeters of distilled water.
Standard Potassium Permanganate. — Dissolve 2 grams of
potassium permanganate in 1,000 cubic centimeters of distilled
water. Standardize by using Bureau of Standard sodium
oxalate.1 Adjust the solution so that i cubic centimeter is
equivalent to o.io per cent, chromium on the basis of a i-gram
sample.
The factor Na2C2O4 — > Cr= 0.2584 (using the 1913 atomic
weights).
Ferrous Sulphate. — Dissolve 25 grams of ferrous ammonium
sulphate in 900 cubic centimeters of distilled water and 100
cubic centimeters of sulphuric acid (i : i).
METHOD.
In a 300 cubic centimeter Erlenmeyer flask, dissolve 1.25
grams (procedure No. i) or i gram (procedure No. 2) of the
steel in 50 cubic centimeters of the sulphuric acid. When com-
pletely dissolved, add 5 cubic centimeters of the nitric acid, and
boil until clear and free from oxides of nitrogen. Dilute with
hot water to approximately 150 cubic centimeter volume, heat,
and while boiling add the potassium-permanganate solution
slowly until a permanent brown precipitate appears (see
notes). Complete the determination by either of the following
procedures :
1 Circular No. 40, Bureau of Standards, Oct. i, 1912.
1. Add 25 cubic centimeters of ammonium hydroxide, spe-
cific gravity 0.90, shake well, place on the cooler part of the hot
plate to avoid bumping. Shake occasionally and digest for
about 15 minutes, or until the permanganate is all decomposed,
then add cautiously 20 cubic centimeters of the sulphuric acid
and bring gently to a boil. Cool the solution and pour into a
volumetric 250 cubic centimeter flask. Make up to mark with
cold water and mix thoroughly. Allow precipitate to settle,
filter off 200 cubic centimeters of the clear solution (equal to
i gram), add the ferrous-sulphate solution in measured amount
(in excess) and titrate back with the standard potassium-per-
manganate solution to a permanent pink color. The number
of cubic centimeters of the standard potassium-permanganate
solution obtained, subtracted from the number corresponding
to the volume of the ferrous-sulphate solution used, will give
the volume of the standard potassium-permanganate solution
equivalent to the chromium in the sample.
2. Add 10 cubic centimeters of hydrochloric acid (i : i), and
boil until the solution is clear and all manganese dioxide dis-
solved. Cool, dilute the solution with water to 300 cubic centi-
meter volume, add the ferrous-sulphate solution in measured
amount (in excess), and titrate back with the standard po-
tassium-permanganate solution to a permanent pink color.
NOTES.
In oxidizing with the potassittm-permanganate solution care should
be taken to avoid a large excess, since the manganese-dioxide precipi-
tate tends to hold the chromic acid.
In the solution of the manganese dioxide under procedure No. 2,
the boiling should be continued until all chlorine fumes are expelled.
The ferrous-sulphate solution should be compared on the day it is
used with the standard potassium-permanganate solution.
Determination of Nickel.
See the Determination of Nickel in Plain Carbon Steel by
the Gravimetric-Dimethylglyoxime Method.1
i Standard Methods for Chemical Analysis of Plain Carbon Steel (Serial Designa-
tion: A 33), 1915, Year-Book, p. 201.
312
See the Determination of Nickel in Plain Carbon Steel by
the Volumetric Dimethylglyoxime Method (Routine).
VANADIUM STEEL.
Determination of Carbon.
See the Determination of Carbon in Plain Carbon Steel by
the Direct-Combustion Method.
Determination of Manganese.
See the Determination of Manganese in Chrome-Nickel
Steel by the Zinc Oxide-Bismuthate Method.
For the Routine Determination of Manganese, see the De-
termination of Manganese in Plain Carbon Steel by the Bis-
muthate Method.
Determination of Phosphorus by the Modified
Molybdate-Magnesia Method.
SOLUTIONS REQUIRED.
Nitric Acid. — Mix 1,000 cubic centimeters of nitric acid,
specific gravity 1.42, and 1,200 cubic centimeters of distilled
water.
Nitric Acid for Washing. — Mix 20 cubic centimeters of
nitric acid, specific gravity 1.42, and 1,000 cubic centimeters
of distilled water.
Potassium Permanganate. — Dissolve 25 grams of potassium
permanganate in 1,000 cubic centimeters of distilled water.
Sodium Bisulphite. — Dissolve 30 grams of sodium bisulphite
in 1,000 cubic centimeters of distilled water.
Ammonium Molybdate. — Solution No. I, — Place in a beaker
100 grams of 85 per cent, molybdic acid, mix it thoroughly
with 240 cubic centimeters of distilled water, add 140 cubic
centimeters of ammonium hydroxide, specific gravity 0.90, fil-
ter, and add 60 cubic centimeters of nitric acid, specific gravity
1.42.
Solution No. 2. — Mix 400 cubic centimeters of nitric acid,
specific gravity 1.42, and 960 cubic centimeters of distilled
water.
When the solutions are cold, add solution No. I to solution
No. 2, stirring constantly; then add o.i gram of ammonium
phosphate dissolved in 10 cubic centimeters of distilled water,
and let stand at least 24 hours before using.
Magnesia Mixture. — Dissolve 50 grams of magnesium chlo-
ride and 125 grams of ammonium chloride in 750 cubic centi-
meters of distilled water and then add 150 cubic centimeters
of ammonium hydroxide, specific gravity 0.90.
Ammonium Hydroxide, Approximately 10 per cent. — Mix
1,000 cubic centimeters of ammonium hydroxide, specific
gravity 0.90, and 2,000 cubic centimeters of distilled water.
Ferrous Sulphate. — A saturated solution; approximately 40
grams of ferrous sulphate and 100 cubic centimeters of dis-
tilled water.
METHOD.
In a 300 cubic centimeter Erlenmeyer flask dissolve 5 grams
of steel in 75 cubic centimeters of the nitric acid. Heat, and
while boiling add about 12 cubic centimeters of the potassium-
permanganate solution, and continue boiling until manganese
dioxide precipitates. Dissolve the precipitate by additions of
the sodium-bisulphite solution, boil until clear and free from
oxides of nitrogen. Cool to 15-20° C., add 5 cubic centimeters
of the ferrous-sulphate solution, and 2 or 3 drops of con-
centrated sulphurous acid, and then 100 cubic centimeters of
the ammonium-molybdate solution. Let stand I minute, shake
or agitate thoroughly for 5 minutes, filter on a 9-centimeter
paper and wash at least 3 times with the 2 per cent, nitric acid
solution to free from iron.
Treat the precipitate on the filter with the 10 per cent, am-
monium-hydroxide solution, letting the solution run into a
100 cubic centimeter beaker containing 10 cubic centimeters of
hydrochloric acid, specific gravity 1.20, and 0.5 gram of citric
acid; add 30 cubic centimeters of ammonium hydroxide,
3*4
specific gravity 0.90, cool, and then add 10 cubic centimeters of
the magnesia mixture very slowly, while stirring the solution
vigorously. Set aside in a cool place for 2 hours, filter and
wash with the 10 per cent, ammonium-hydroxide solution. Ig-
nite and weigh. Dissolve the precipitate of magnesium pyro-
phosphate with 5 cubic centimeters of nitric acid, specific
gravity 1.20, and 20 cubic centimeters of water, filter and
wash with hot water. Ignite and weigh. The difference in
weights represents pure magnesium pyrophosphate containing
27.84 per cent, of phosphorus.
NOTE.
The ammonium-molybdate solution should be kept in a cool place
and should always be filtered before using.
Determination of Phosphorus by the Modified
Alkalimetric Method.
(Routine.)
SOLUTIONS REQUIRED.
Nitric Acid. — Mix 1,000 cubic centimeters of nitric acid,
specific gravity 1.42, and 1,200 cubic centimeters of distilled
water.
Nitric Acid for Washing. — Mix 20 cubic centimeters of
nitric acid, specific gravity 1.42, and 1,000 cubic centimeters of
distilled water.
Potassium Permanganate. — Dissolve 25 grams of potassium
permanganate in 1,000 cubic centimeters of distilled water.
Sodium Bisulphite. — Dissolve 30 grams of sodium bisulphite
in 1,000 cubic centimeters of distilled water.
Ammonium Molybdate. — Solution No. i. — Place in a beaker
100 grams of 85 per cent, molybdic acid, mix it thoroughly
with 240 cubic centimeters of distilled water, add 140 cubic
centimeters of ammonium hydroxide, specific gravity 0.90, fil-
ter, and add 60 cubic centimeters of nitric acid, specific gravity
1.42.
Solution No. 2. — Mix 400 cubic centimeters of nitric acid,
specific gravity 1.42, and 960 cubic centimeters of distilled
water.
When the solutions are cold, add solution No. I to solu-
tion No. 2, stirring constantly; then add o.i gram of ammoni-
um phosphate dissolved in 10 cubic centimeters of distilled
water, and let stand at least 24 hours before using.
Ferrous Sulphate. — A saturated solution; approximately 40
grams of ferrous sulphate and 100 cubic centimeters of dis-
tilled water.
Potassium Nitrate, I per cent. — Dissolve 10 grams of potas-
sium nitrate in 1,000 cubic centimeters of distilled water.
Phenolphthalein Indicator. — Dissolve 0.2 gram of phenol-
phthalein in 50 cubic centimeters of 95 per cent, ethyl alcohol
and 50 cubic centimeters of distilled water.
Standard Sodium Hydroxide. — Dissolve 6.5 grams of puri-
fied sodium hydroxide in 1,000 cubic centimeters of distilled
wrater, add a slight excess of I per cent, solution of barium
hydroxide, let stand for 24 hours, decant the liquid, and
standardize it against a steel of known phosphorus content,
as determined by the molybdate magnesia method, so that I
cubic centimeter will be equivalent to o.oi per cent, of phos-
phorus on the basis of a 2-gram sample (see notes). Protect
the solution from carbon dioxide with a soda-lime tube.
Standard Nitric Acid. — Mix 10 cubic centimeters of nitric
acid, specific gravity 1.42, and 1,000 cubic centimeters of dis-
tilled water. Titrate the solution against the standardized
sodium hydroxide, using phenolphthalein as indicator, and
make it equivalent to the sodium hydroxide by adding dis-
tilled water.
METHOD.
In a 300 cubic centimeter Erlenmeyer flask dissolve 2 grams
of steel in 50 cubic centimeters of the nitric acid. Heat, and
while boiling add 6 cubic centimeters of the potassium per-
manganate solution and continue boiling until manganese
dioxide precipitates. Dissolve this precipitate by additions of
the sodium bisulphite solution, boil until clear and free from
3i6
oxides of nitrogen, cool to I5°-2O° C., add 5 cubic centimeters
of the ferrous sulphate solution and 2 or 3 drops of concen-
trated sulphurous acid, and then 50 cubic centimeters of the
ammonium molybdate solution. Let stand for i minute, shake
or agitate for 5 minutes, filter on a 9 centimeter paper,
wash the precipitate three times with the 2 per cent, nitric
acid solution to free it from iron, and continue the washing
with the i per cent, potassium nitrate solution until the pre-
cipitate and flask are free from acid.
Transfer the paper and precipitate to the solution flask, add
20 cubic centimeters of distilled water (see notes), 5 drops of
phenolphthalein solution as indicator, and an excess of the
standard sodium hydroxide solution. Insert a rubber stopper
and shake vigorously until solution of the precipitate is com-
plete. Wash off the stopper with distilled water and deter-
mine the excess of standard sodium hydroxide solution by
titrating with standard nitric acid solution. Each cubic centi-
meter of standard sodium hydroxide solution represents o.oi
per cent, of phosphorus.
NOTES.
The ammonium-molybdate solution should be kept in a cool place
and should always be filtered before using.
All distilled water used in titration should be freed from carbon
dioxide by boiling or otherwise.
Bureau of Standards Standard Steel No. 24 is recommended as a
suitable steel for standardizing the sodium-hydroxide solution.
Determination of Sulphur.
See the Determination of Sulphur in Plain Carbon Steel
by the Oxidation Method.
See the Determination of Sulphur in Plain Carbon Steel by
the Evolution-Titration Method (Routine).
NOTES.
The Evolution-Titration Method should not be used with steels
containing appreciable amounts of tungsten, or of copper or other
metals precipitated by hydrogen sulphide from acid solutions.
The annealing of the steel drillings has been found by a number
of investigators to increase the degree of refinement of the method.
Determination of Silicon.
See the Determination of Silicon in Plain Carbon Steel by
the Nitro-Sulphuric Method.1
See the Determination of Silicon in Plain Carbon Steel by
the Sulphuric Acid Method (Optional).1
Determination of Vanadium by the Phosphomolybdate-Pre-
cipitation Method.
SOLUTIONS REQUIRED.
Nitric Acid. — Mix 1,000 cubic centimeters of nitric acid,
specific gravity 1.42, and 1,200 cubic centimeters of distilled
water.
Nitric Acid for Washing. — Mix 20 cubic centimeters of
nitric acid, specific gravity 1.42, and 1,000 cubic centimeters
of distilled water.
Potassium Permanganate. — Dissolve 25 grams of potassium
permanganate in 1,000 cubic centimeters of distilled water.
Sodium Bisulphite. — Dissolve 30 grams of sodium bisulphite
in 1,000 cubic centimeters of distilled water.
Ammonium Phosphate. — Dissolve 50 grams of ammonium
phosphate in 1,000 cubic centimeters of distilled water.
Ammonium Molybdate. — Solution No. I. — Place in a beaker
100 grams of 85 per cent, molybdic acid, mix it thoroughly
with 240 cubic centimeters of distilled water, add 140 cubic
centimeters of ammonium hydroxide, specific gravity 0.90,
filter, and add 60 cubic centimeters of nitric acid, specific
gravity 1.42.
Solution No. 2. — Mix 400 cubic centimeters of nitric acid,
specific gravity 1.42, and 960 cubic centimeters of distilled
water.
When the solutions are cold, add solution No. I to solution
No. 2, stirring constantly; then add o.i gram of ammonium
phosphate dissolved in 10 cubic centimeters of distilled water,
and let stand at least 24 hours before using.
1 Standard Methods for Chemical Analysis of Plain Carbon Steel (Serial Designa-
tion: A 33), 1915 Year-Book, p. 201.
21
Acid Ammonium Sulphate. — Mix 50 cubic centimeters of
sulphuric acid, specific gravity 1.84, and 950 cubic centimeters
of distilled water, and when cold add 15 cubic centimeters of
ammonium hydroxide, specific gravity 0.90. Use at a tem-
perature of 80° C. «
Standard Potassium Permanganate. — Dissolve 0.35 gram
of potassium permanganate in 1,000 cubic centimeters of dis-
tilled water, and standardize by using Bureau of Standards
sodium oxalate.1 Adjust the solution so that i cubic centi-
meter is equivalent to 0.02 per cent, vanadium on the basis
of a 2.5 gram sample.
The factor Na2C2O4 — > V = 0.7612 (using the 1913 atomic
weights).
METHOD.
In a 300 cubic centimeter Krlenmeyer flask dissolve 2.5
grams of steel in 50 cubic centimeters of the nitric acid. Heat,
and while boiling add 6 cubic centimeters of the potassium
permanganate solution and continue boiling until manganese
dioxide precipitates. Dissolve the precipitate by additions of
the sodium bisulphite solution and boil until clear and free
from oxides of nitrogen. Add 5 cubic centimeters of the
ammonium phosphate solution and 10 grams of ammonium
nitrate, heat to boiling, remove from the plate and add im-
mediately 50 cubic centimeters of the ammonium molybdate
solution. Let stand I minute, shake or agitate for 3 minutes,
filter the supernatant liquid by suction through an asbestos
filter, and wash three times with the hot acid ammonium sul-
phate solution. The flask containing the bulk of the precipi-
tate is then set under the funnel fitted into a bell- jar filter
and the asbestos pad is treated with successive small portions
of hot sulphuric acid, specific gravity 1.84. The solution is
then heated until the precipitate is completely dissolved, a
few drops of the nitric acid added, and the heating continued
until copious fumes of sulphuric acid are evolved. Cool the
solution, add hydrogen peroxide in small quantities, with vig-
1 Circular No. 40, Bureau of Standards, Oct. i, 1912.
319
orous shaking after each addition, until the solution takes on a
deep brown color. Replace flask on the hot plate, fume for 4
or 5 minutes, cover the flask, cool, add 100 cubic centimeters
of distilled water, heat to 80° C. and titrate with the stand-
ard potassium permanganate solution to a permanent pink
color.
NOTE.
If, after the addition of hydrogen peroxide and subsequent heating,
the solution does not take on a clear green or blue color, it should be
heated until fumes of sulphuric acid are evolved to rid of any traces
of nitric acid which interferes with the reduction, then cooled and the
treatment with hydrogen peroxide repeated.
Determination of Vanadium by the Ether Extraction Hydro-
chloric Acid Reduction Method.
(Routine.)
SOLUTIONS REQUIRED.
Hydrochloric Acid. — Mix 600 cubic centimeters of hydro-
chloric acid, specific gravity 1.20, and 400 cubic centimeters
of distilled water.
Nitric Acid. — Mix 1,000 cubic centimeters of nitric acid,
specific gravity 1.42, and 1,200 cubic centimeters of distilled
water.
Sulphuric Acid. — Mix 500 cubic centimeters of sulphuric
acid, specific gravity, 1.84, and 500 cubic centimeters of dis-
tilled water.
Potassium Permanganate. — Dissolve 25 grams of potassium
permanganate in 1,000 cubic centimeters of distilled water.
Standard Potassium Permanganate. — Dissolve 0.35 gram of
potassium permanganate in 1,000 cubic centimeters of dis-
tilled water, and standardize by using Bureau of Standards
sodium oxalate.1 Adjust the solution so that I cubic centi-
meter is equivalent to 0.02 per cent, vanadium on the basis of
a 2.5-gram sample.
1 Circular No. 40. Bureau of Standards, Oct. i, 1912.
320
The factor Na2C2O4 — > ¥ = 0.7612 (using the 1913 atomic
weights).
METHOD.
. In a 150 cubic centimeter beaker dissolve 2.5 grams of the
steel in 50 cubic centimeters of the hydrochloric acid, add
small portions of the nitric acid to oxidize the iron, and heat
to expel the oxides of nitrogen. Cool, and transfer the solu-
tion into an 8-ounce separatory funnel, rinsing the beaker with
small portions of the hydrochloric acid. Add 50 cubic centi-
meters of ether, shake for 5 minutes, let settle for i minute,
and then draw off lower clear solution into another 8-ounce
separatory funnel. Add 10 cubic centimeters of hydrochloric
acid, specific gravity 1.20, -to the solution in the first separa-
tory funnel, shake thoroughly, allow to settle for i minute,
and then draw off the lower clear solution into the second
separatory funnel. To the combined solutions in the second
separatory funnel add 50 cubic centimeters of ether, shake
for 5 minutes, let settle for I minute, and then draw off the
clear layer into a 150 cubic centimeter beaker. Heat the
aqueous solution gently to expel the ether, add 25 cubic centi-
meters of the sulphuric acid, and heat until copious fumes are
evolved. Cool, dilute with 25 cubic centimeters of water, add
a slight excess of the potassium permanganate solution, and
boil. Add 15 cubic centimeters of hydrochloric acid, specific
gravity 1.20, and heat to fuming for 10 minutes. Cool, add
loo cubic centimeters of water, heat to 80° C., and titrate
with the standard potassium permanganate solution to a per-
manent pink color.
NOTE.
In heating the solution to expel oxides of nitrogen care should be
taken not to boil.
CHROMA- VANADIUM
Determination of Carbon.
See the Determination of Carbon in Plain Carbon Steel by
the Direct Combustion Method.1
1 Standard Methods for Chemical Analysis of Plain Carbon Steel (Serial Designa-
tion: A 33), 1915 Year-Book, p. 201.
321
Determination of Manganese.
See the Determination of Manganese in Chrome-Nickel
Steel by the Zinc Oxide Bismuthate Method.
See the Determination of Manganese in Chrome-Nickel
Steel by the Modified Bismuthate Method.
Determination of Phosphorus.
See the Determination of Phosphorus in Vanadium Steel by
the Modified Molybdate Magnesia Method.
See the Determination of Phosphorus in Vanadium Steel by
the Modified Alkalimetric Method (Routine).
Determination of Sulphur.
See the Determination of Sulphur in Plain Carbon Steel by
the Oxidation Method.1
See the Determination of Sulphur in Plain Carbon Steel by
the Evolution-Titration Method (Routine).
NOTES.
The Evolution-Titration Method should not be used with steels
containing appreciable amounts of tungsten, or of copper or other
metals precipitated by hydrogen sulphide from acid solutions.
The annealing of the steel drillings has been found by a number
of investigators to increase the degree of refinement of the method.
Determination of Silicon.
See the Determination of Silicon in Plain Carbon Steel by
the Nitro-Sulphuric Method.
See the Determination of Silicon in Plain Carbon Steel by
the Sulphuric Acid Method (Optional).
Determination of Chromium by the Fusion Method.
SOLUTIONS REQUIRED.
Sulphuric Acid.— Mix 1,000 cubic centimeters of sulphuric
acid, specific gravity 1.84, and 3,000 cubic centimeters of dis-
tilled water.
1 Standard Methods for Chemical Analysis of Plain Carbon Steel (Serial Designa-
tion: A 33), 1915 Year-Book, p. %oi.
322
Sodium Carbonate. — A saturated solution; approximately
60 grams of sodium carbonate and 100 cubic centimeters of
distilled water.
Magnesium Carbonate. — Ten grams of finely divided mag-
nesium carbonate suspended in 100 cubic centimeter of distilled
water.
Barium Carbonate. — Ten grams of finely divided barium
carbonate suspended in 100 cubic centimeters of distilled
water.
Nitric Acid. — Mix 1,000 cubic centimeters of nitric acid,
specific gravity 1.42, and 1,200 cubic centimeters of distilled
water.
Potassium Ferricyanide Indicator. — Dissolve o.i gram of
potassium ferricyanide in 50 cubic centimeters of distilled
water (see notes).
Standard Potassium Bichromate. — Dissolve 5 grams of
potassium bichromate in 1,000 cubic centimeters of distilled
water, standardize against pure ferrous ammonium sulphate,
and adjust to tenth-normal.
Ferrous Sulphate. — Dissolve 25 grams of ferrous ammonium
sulphate in 900 cubic centimeters of distilled water and 100
cubic centimeters of sulphuric acid (i: i). The strength of
this solution should be expressed in terms of chromium and
vanadium.
METHOD.
In a 300 cubic centimeter Erlenmeyer flask, covered, dissolve
i gram of steel in 50 cubic centimeters of the sulphuric acid
(see notes). When completely dissolved, add 50 to 75 cubic
centimeters of hot water, then gradually the sodium carbonate
solution until near neutrality, and then add an excess of the
magnesium carbonate suspension (see notes), and boil vigor-
ously for 15 minutes, with the cover on, adding fresh portions
of the carbonate suspension during this time, so that there is
present in the solution at the end of the operation an excess
of 2 to 3 grams of the carbonate. Let settle and pour the
supernatant liquid on a rapid filter, washing by decantation
3^3
twice with cold water, pouring the washings through the filter.
Transfer the filter to a platinum crucible and after burning
off the paper, fuse the residue for 10 minutes with a mixture
of 5 grams of sodium carbonate and 0.25 gram of potassium
nitrate. Dissolve the fusion in water, transfer to a beaker,
add 2 cubic centimeters of 3 per cent, hydrogen peroxide, boil
a few minutes and filter. Add 20 cubic centimeters of the
sulphuric acid, stir vigorously, cool and titrate against the
standardized ferrous sulphate solution, using the potassium
ferricyanide as outside indicator, or add at once a measured
amount (in excess) of the ferrous sulphate solution and
titrate back against the standard potassium bichromate solu-
tion, using the same indicator.
From the number of cubic centimeters of the standard fer-
rous sulphate solution required deduct the number of cubic
centimeters of the standard ferrous sulphate solution equiva-
lent to the vanadium in the steel, as determined by the Phos-
phomolybdate Precipitation Method for Vanadium Steel, and
the result will be the number of cubic centimeters of the
standard ferrous sulphate solution equivalent to the chromium
in the steel.
NOTES.
The solution of the steel may be in hydrochloric acid, specific
gravity 1.20 or any other desired strength, adjusting the amount of
acid used to ?,void a large excess being present.
Barium-carbonate suspension may be substituted for the mag-
nesium-carbonate suspension when hydrochloric acid is used as solvent.
All hydrogen peroxide must be destroyed by boiling before acidi-
fying, otherwise chromic acid will be reduced at this stage.
The insoluble residue remaining after extraction of the fusion
should be examined for chromium.
The potassium ferricyanide indicator should be prepared fresh on
the day it is used.
The ferrous sulphate solution should be standardized on the day
it is used.
In titrating with the ferrous sulphate solution it is convenient to
divide the solution, roughly titrate one portion, add the other and
finish carefully.
324
Determination of Chromium by the Chlorate Method.
(Routine.)
SOLUTIONS REQUIRED.
Nitric Acid. — Mix 1,000 cubic centimeters of nitric acid,
specific gravity 1.42, and 1,200 cubic centimeters of distilled
water.
Potassium Ferricyanide Indicator. — Dissolve o.i gram of
potassium ferricyanide in 50 cubic centimeters of distilled
water (see notes).
Standard Potassium Bichromate. — Dissolve 5 grams of
potassium bichromate in 1,000 cubic centimeters of distilled
water, standardize against pure ferrous ammonium sulphate,
and adjust to tenth-normal.
Standard Potassium Permanganate. — Dissolve 0.5 gram of
potassium permanganate in 1,000 cubic centimeters of distilled
water. Standardize by using Bureau of Standards sodium
oxalate.1 Adjust the solution so that I cubic centimeter is
equivalent to 0.05 per cent, vanadium on the basis of a I gram
sample.
The factor Na2C2O4 — > V = 0.7612 (using the 1913 atomic
weights).
Ferrous Sulphate. — Dissolve 25 grams of ferrous ammonium
sulphate in 900 cubic centimeters of distilled water and 100
cubic centimeters of sulphuric acid ( I : I ) . The strength of
this solution should be expressed in terms of chromium and
vanadium.
METHOD.
In a 300 cubic centimeter Erlenmeyer flask dissolve I gram
of the steel in 30 cubic centimeters of the nitric acid, and
evaporate rapidly to approximately one-half volume. Add 50
cubic centimeters of nitric acid, specific gravity 1.42, and I
gram of sodium chlorate (see notes). Evaporate by boiling
to one-half volume, dilute with 100 cubic centimeters of
water and filter off the manganese dioxide, using suction,
1 Circular No. 40, Bureau of Standards, Oct. i, 1912.
325
washing with hot water. Cool the solution to room tempera-
ture and complete the determination by either of the follow-
ing procedures :
1. Titrate against the ferrous sulphate solution, using the
potassium ferricyanide solution as outside indicator (see
notes). From the number of cubic centimeters of the ferrous
sulphate solution required deduct the number of cubic centi-
meters of the ferrous sulphate solution equivalent to the va-
nadium in the steel, as determined by the Phosphomolybdate
Precipitation Method for Vanadium Steel, and the result will
be the number of cubic centimeters of the ferrous sulphate
solution equivalent to the chromium in the steel.
2. Titrate against the ferrous sulphate solution, using the
potassium ferricyanide solution as outside indicator (see
notes). Cool to 15° C. and titrate against the standard potas-
sium permanganate solution to a pink color permanent for 10
seconds. Deduct the number of cubic centimeters of the
standard potassium permanganate solution consumed, which
gives a direct measure of the vanadium content of the steel,
from the first titration; the remainder will represent the
chromium content of the steel.
NOTES.
The potassium-ferricyanide indicator should be prepared fresh on
the day it is used.
The ferrous-sulphate solution should be compared on the day it
is used with the standard potassium-permanganate or potassium-
bichromate solutions.
Potassium chlorate may be used as oxidizing agent in the place of
sodium chlorate.
In titrating with the ferrous-sulphate solution it is convenient to
divide the solution, roughly titrate one portion, add the other and
finish carefully.
Determination of Vanadium.
See the Determination of Vanadium in Vanadium Steel by
the Phosphomolybdate Precipitation Method.
326
Determination of Vanadium by the Ether Extraction Hydro-
chloric Acid Reduction Method.
(Routine.}
SOLUTIONS REQUIRED.
Hydrochloric Acid. — Mix 500 cubic centimeters of hydro-
chloric acid, specific gravity 1:20, and 500 cubic centimeters of
distilled water.
Standard Potassium Permanganate. — Dissolve 2 grams of
potassium permanganate in 1,000 cubic centimeters of dis-
tilled water, and standardize by using Bureau of Standards
sodium oxalate.2 Adjust the solution so that I cubic centi-
meter is equivalent to o.io per cent, vanadium on the basis of
when a 5-gram sample.
The factor Na2C2O4 — > V = 0.7612 (using the 1913 atomic
weights).
METHOD.
In a 150 cubic centimeter beaker, dissolve 5 grams of the
steel in 60 cubic centimeters of the hydrochloric acid, add
small portions of nitric acid, specific gravity 1.42, to oxidize
the iron, avoiding an excess, and heat to expel the oxides of
nitrogen. Cool, and transfer the solution into an 8-ounce
separatory funnel, rinsing the beaker with small portions of
the hydrochloric acid. Add 50 cubic centimeters of ether,
shake for 5 minutes, let settle for i minute, and then draw off
lower clear solution into another separatory funnel. Add 10
cubic centimeters of hydrochloric acid, specific gravity 1.20,
to the solution in the first separatory funnel, shake thoroughly,
allow to settle for i minute, and then draw off the lower clear
solution into the second separatory funnel. To the combined
solution in the second separatory funnel add 50 cubic centi-
meters of ether, shake for 5 minutes, let settle for i minute,
and then draw off the clear layer into a 150 cubic centimeter
beaker. Heat the aqueous solution gently to expel the ether,
evaporate to approximately one- fourth original volume, add
2 Circular No. 40, Bureau of Standards, Oct. i, 1912.
327
O.5 gram of potassium chlorate and boil down to a volume of
10 cubic centimeters. Add 25 cubic centimeters of hydro-
chloric acid, specific gravity 1.20, and again evaporate to 10
cubic centimeters. Add 20 cubic centimeters of sulphuric
acid, specific gravity 1.84, and evaporate until copious fumes
of sulphuric acid are evolved. Cool, dilute with water to 100
cubic centimeters volume, and titrate against the standard
potassium permanganate to a pink color permanent for 10
seconds. Deduct the chromium blank and the remainder is
equivalent to the vanadium content of the steel.
NOTE.
If much chromium relative to the vanadium is present the result
will be high due to the oxidation of a portion of the chromium by the
permanganate, and should be corrected by a blank which varies with
the amount of the chromium present. This blank is conveniently made
by putting a suitable amount of a chrome or chrome-nickel steel,
free from vanadium, through the above process. By using varying
amounts of this steef, so as to vary the chromium correspondingly, a
curve may be constructed showing the relation between amount of
chromium present and the amount of blank, and this curve can then
be used in all subsequent work.
SIUCO-MANGANESE;
Determination of Carbon.
See the Determination of Carbon in Plain Carbon Steel by
the Direct Combustion Method.1
Determination of Manganese.
See the Determination of Manganese in Plain Carbon Steel
by the Bismuthate Method. . '
See the Determination of Manganese in Plain Carbon Steel
by the Persulphate Method (Routine).
Determination of Phosphorus.
See the Determination of Phosphorus in Plain Carbon Steel
by the Molybdate Magnesia Method.
i Standard Methods for Chemical Analysis of Plain Carbon Steel (Serial Designa-
tion: A 33), 1915 Year-Book, p. 201.
328
See the Determination of Phosphorus in Plain Carbon Steel
by the Alkalimetric Method (Routine).
Determination of Sulphur.
See the Determination of Sulphur in Plain Carbon Steel by
the Oxidation Method.
See the Determination of Sulphur in Plain Carbon Steel by
the Evolution-Titration Method (Routine).
NOTES.
The Evolution-Titration Method should not be used with steels
containing appreciable amounts of tungsten, or of copper or other
metals precipitated by hydrogen sulphide from acid solutions.
The annealing of the steel drillings has been found by a number
of investigators to increase the degree of refinement of the method.
Determination of Silicon.
See the Determination of Silicon in Plain Carbon Steel by
the Nitro-Sulphuric Method.
See the Determination of Silicon in Plain Carbon Steel by
the Sulphuric Acid Method (Optional).
CONVERSION TABLE USED IN WATER ANALYSIS.
Factor
Na20
to Na2SO.t
2.29
S03
" "
J-775
Cl
'• NaCl
1.6486
NaCl
" Na2O
0.53028
Na2O
V NaCl
1.8858
Na20
" Na2CO3
1.71
CaO
" CaC03
1.7844
MgO
" MgC03
2.1
S03
" CaSO4
1-7
S03
11 MgS04
i-5
Cl
" CaCl2-
1-563
MgO
" MgCl2
2.4
Cl
" MgCl,
1-34
MgO
" Mg
0.6
MgO
" MgS04
3-o
CaS04
" CaCO3
0.736
Mg2P20T
" MgO
0.36
BaSO4
" S
0.137
BaSO4
" S03
0-343
Factor
AgCl
to Cl
0.247
CaC03
" CO2
°-439
MgC03
» C02
0.521
Na2S04
" Na2O
0.4366
CaO
" CaCl2
1.9777
CaO
" CaS04
2.4
CaS04
" CaO
0.412
Na2C03
•' C02
0.415
SO3
" CaS04
1.7005
CaO
" CaCO3
1.7844
NgO
" NgC03
2.0912
Na20
" NaCl
1.8858
Cl
" NaCl
1.6486
CaC03
" C02
0.4396
MgC03
'• C02
0.5218
NaCl
" Na
0-3934
Na
" Na20
1-3478
Na2O
" Na
0.7419
MgO
V Mg
0.603
Mg
" MgO
1-657
329
TABLES FOR CALCULATING ANALYSIS.
Sought
Found
Factor
Ag
AgBr
0-5744
AgCl
0.7527
Ag2S
0.8707
Al
A12O3
0.5303
As
As2S3
0.0093
As2S5
0.4834
(NH4MgAsO02.H2O
0.3938
Mg2As->O7
0.4828
Mg2P26r
0.6736
BaS04
O.2I4I
As2O3
As2S3
0.8042
As.Ss
0.6381
(NH4MgAsO4)2.H2O
0.5198
MgaAsaOr
0.6373
Mg2P2O7
0.8891
BaSO4
0.2827
As2O8
As2S3
0.9342
As2Ss
0.7412
(NH4MgAsO4)2.H20
0.6038
Mg^SaOi
0.7403
Mg2P207
1.0328
BaSO4
0.3284
AsOa
As2S3
0.9992
As2S5
0.7928
(NH4MgAsO4)2.H2O
0.6458
Mg2As2O7
0.7918
Mg2P2Oi
1.1046
BaSO4
0.3512
AsO*
As2S3
I.I29I
As2S0
0.8959
(NH4MgAsO4)2.H2O
0.7298
Mg2As2O7
0.8947
Mg2P2O7
1.2483
BaSO*
0.3969
Ba
BaC03
0.6961
BaCrO4
0.5420
BaS04
0.5886
BaSiF6
0.4906
BaCO3
BaCr04
0.7787
Ba(NOi),
BaCr04
I.03I4
BaO
BaC03
0-7771
BaCrO4
0.0051
BaSO4
0.6571
BaSiF6
0.5478
Be
BeO
0.3626
Bi
Bi2O3
0.8968
BiOCl
O.8OI9
Bi2S3
0.8125
Br
AgBr
0.4255
I,og
.75924
.87665
.93986
.72455
.78480
.68431
.59528
.68375
.82837
.33070
.90538
.80489
.71586
.80433
.94895
45128
.97044
.86995
.78092
.86939
.OI4OI
.51634
.99965
.89916
.81013
.89860
.04322
•54555
.05275
.95226
.86323
.95170
.09632
.59865
.84266
•73401
.76981
.69077
•89135
.01342
.89049
.78184
.81764
.73860
•55937
.95209
.90414
.90985
.62895
330
TABLES FOR CALCULATING ANALYSIS.— (Continued)
Sought Found
C CO2
CN AgCN
C02 CaC03
CaO
MgO
CO3 ... CO2 •
Ca CaCO3
CaO
CaSO4
CaCOs CaS04
CaO CO2
CaCO3
CaSO4
CaSO4.2H2O
CaSO., BaS04
Cd CdO
CdS
CdSO4
CdO CdS
Ce Ce2O3
CeO2
Cl Ag
AgCl
Co Co3O4
CoSO4
CoO Co
CoSO4
Cr Cr2O3
PbCrO*
Cr2O3 PbCrO4
CrOs Cr2O3
PbCrO4
Cr04 Cr203
PbCrO4
Cs Cs2S04
Cu CuO
CUaS
CuFeS2 Cu2S
Cu2O CuO
CuO Cu
Cu2S
CuSO4.sH2O Cu
Cu2S
Er Er2O3
F , ' CaF2
Factor
l*g
0.2727
•43573
0.1944
.28860
04394
.64289
0.7839
•89425
I.09O2
.03750
1.3636
.13470
0.4008
.60291
0.7149
-85427
0.2947
46932
0.7352
.86641
1-2757
.10575
0.5606
.74864
O4I2I
.61505
0.3259
.51312
0.5833
.76588
0.8754
.94220
0-7779
.89000
0.5391
.73166
0.8886
.94870
0.8539
.93139
0.8140
.91064
0.3285
.51650
0.2473
.39315
0-7344
.86595
0.3804
.58024
1.2712
.10421
04837
.68456
0.6847
.83550
0.1613
.20776
0.2356
.37226
I-3I53
.11902
0.3099
49128
1.5255
.18341
0-3595
.55567
0-7344
.86596
0.7990
•90255
0.7987
.90238
2.3056
.36279
0.8995
.95400
1.2516
.09745
0.9996
.99983
3-9267
.59403
3-1362
49641
0.9737
.94136
0.4870
.68756
TABLES FOR CALCULATING ANALYSIS.— (Continued)
Sought Found Factor I/>g
Fe Fe2OG 0.6996 .84482
FeO Fe 1.2863 -10935
Fe2O6 0.8999 .95417
Fe2O3 Fe 1.4295 .15518
FePO4 0.5294 .72375
FeS2 Fe2O6 1.5022 .17674
H H2O 0.119 .04869
HBr . AgBr 0.4309 .63439
HC1 AgCl 0.2543 40532
HJ AgJ 0.5448 .73626
HNO3 NH4C1 1.1781 .07117
(NHOJPtCl. 0.2842 ' 45363
NO 2.0989 .32199
Pt 0.6473 .81113
H2SOi BaSO4 0.4201 .62331
Hg HgCl 0.8493 .92904
HgS 0.8617 .93535
J AgJ 0.5405 .73282
PdJ2 0.7046 .84795
K KC1 0.5248 .71999
KC1O4 0.2825 .45097
K2PtCl6 0.1612 .20730
K2SO4 0.4491 .65231
Ft 0.4019 .60417
K2O KC1 0.6320 .80074
KC1O4 0.3402 .53172
K2PtCl6 0.1941 .28805
K2SO4 0.5408 .73306
Pt 0.4841 .68492
K2SO, BaS04 0.7468 .87318
La La2O3 0.8527 .93078
Mg MgO 0.6036 .78073
MgzPaOi 0.2188 -33999
MgCOo Mg2P2O7 0.7576 .87945
MgO Mg2P2Oi 0.3625 .55926
Mn Mn3O4 0.7205 .85764
Mn2P2Or 0.3873 .58807
MnS 0.6315 .80034
MnCO3 Mn3O4 1.5066 .17798
MnO Mn3O4 0.9301 .96854
MnS 0.8152 .91124
Mo MoO3 0.6667 .82391
MoS2 0.5096 .77788
N NH4C1 0.2623 .41885
(NH4)2PtCl« 0.06329 .80131
Pt 0.1441 .15881
NH3 0.8235 .91566
\ 332
TABLES FOR CALCULATING ANALYSIS.— (Continued)
Sought Found
NH8 ...................... NH4C1
(NH4)2PtCl6
Pt
NH4 ....................... NH4C1
(NH4)2PtCl8
Pt
NO3 .................... ... NH.C1
(NH4)2PtCl6
NO
Pt
N2O5 ...................... NH4C1
(NH4)2PtCl6
NO
Pt
Na ........................ NaCl
Na2SO4
Na2O ...... ............... NaCl
Na2SO*
Ni ......................... NiO
NiO ....................... Ni
P ......................... Mg2P2O?
(NH4)3PO4.i2MoO3
P2O5.24MoO3
P2O6 ...................... MgiPaOr
(NH4)3PO4.i2MoO3
P2O5.24MoO3
PO4 ....................... Mg2P2O7
(NH4)3PO4.i2MoO3
P2O5.24MoO3
P2O5 ....... ................ P
Pb ........................ PbCrO4
PbO
PbO2
PbS
PbSO4
PbO ....................... PbCrO4
PbO2
PbS
PbSO4
PbS ....................... PbSCX
Rb ........................ Rb2SO4
S .......................... BaSO4
503 ....................... BaSO4
504 ....................... BaSO*
Sb .. ....................... Sb2O4
Sb2S:j
Factor
0.3177
0.07690
0.1752
0.3376
0.08145
0.1855
1.1592
0.2796
2.0652
0.6370
1.0097
0.2436
1.7090
0.5548
0.3940
0.3243
0.5308
0.4368
0.7858
1.2726
0.2784
0.01639
0.01723
0.6376
0.03753
0.03947
0.8532
0.05022
0.05281
2.3
0.6405
0.9282
0.8660
0.8658
0.6829
0.6901
0.9330
0.9328
0.7357
0.7888
0.6402
0.1373
0.3429
0.4114
0.7898
0.7142
0.5999
.50346
.88592
.24342
.52844
.91090
.26840
.06415
.44661
.31497
.8041 1
.00430
.38666
.25502
.74416
-59551
.51092
.72490
.64031
.89532
.10468
.44467
.21448
.23633
.80457
-57438
.59623
.93103
.70084
.72269
.36172
.80654
.96765
.93754
.93743
.83438
.83889
.96989
.96978
-86673
.89695
.80633
.13769
.53515
.61427
,89749
.85382
333
TABLES FOR CALCULATING ANALYSIS.— (Continued)
Sought Found Factor I,og
SbzOs V. SbsO* 0.9475 .97656
Sb2S3 0.8568 .93289
Sb2S5 0.7198 .85718
Sb2S3 Sb2O4 1.1058 .04367
SeO2 Se 1.4040 .14737
SeO3 , Se 1.6061 .20576
Si SiO2 0.4702 .67228
SiO3 SiO2 1.2649 .10205
Shd SiO2 1-3973 -I453O
SiO* SiO2 1.5298 .18463
Sn SnO2 0.7881 .89657
Sr SrCO3 0.5936 .77350
SrCCX 0.4771 .67859
SrCOa Sr(NO3)2 0.6973 -84344
Sr(OH)2.8H20 0.5555 -74468
SrS 1.2334 .09111
SrS.Os 0.7391 .86869
Sr(OH)2.8H20 Sr(N03)2 1.2553 .09876
Sr(SH)2 1.7283 .23762
SrS2O3 1.3305 -12401
SrSO* '. BaSO* 0.7868 .89584
TeO2 Te 1.2508 .09718
TeO3 Te 1.3762 .13867
Th Th(NO3)44H2O 0.4207 .62393
ThO2 0.8700 -94399
Ti TiO2 0.6007 .77866-
U Na2U2Ot 0.7511 .87568
UO2 0.8817 .94532
U3O8 0.8482 .92852
W WO3 0.7931 .89933
Y Y2O3 0.7876 .80631
Zn ZnO 0.8035 -90496
ZnS 0.6710 .82675
ZnO ZnS 0.8352 .92179
ZnS ZnO I.I973 -07821
ZnSO4.7H2O ZnO 3-5329 -548i3
ZnS 2.9507 .46992
Zr ZrO2 0.7300 .86864
22
334
GAS FACTORS.
Grams per M3 X 43-7 = grains per 100 cubic feet.
Grams per M3 X 0.437 — grains per cubic foot.
Grains per cubic foot X 2.288 = grams per M3.
Grains per 100 cubic feet X 0.02288 = grams per M3.
Grams per cubic foot X 35-31 = grams per M3.
Grams benzine per MS X 0.0088 = gallons per 1,000 cubic feet.
I MS of gas at o° C. and 760 millimeters = 1.05505 M3 at 15° C. and
760 millimeters.
i M3 of gas at o° C. and 760 millimeters = 1.0734 M3 at 20° C. and
760 millimeters.
i MS of gas at 15° C. and 760 millimeters = 0.94782 MS at o° C. and
760 millimeters.
i MS of gas at 20° C. and 760 millimeters = 0.93162 MS at o° C. and
760 millimeters.
Vapor tension divided by total pressure = percentage by volume of
vapor in saturated gas.
22.37 liters of any true gas or vapor, at o° C. and 760 millimeters pres-
sure, has a weight in grams equal to its molecular weight.
Hence it follows that the molecular weight of any gas or vapor
divided by 22.37 gives the weight in kilos of a cubic meter of
that gas.
Gas at o° C. X 1.367 = volume at 100° C.
335
O M o
8* $ vS *£•
*-• O ^O t***
•g 8 o <T o
0* 0* M O* 0 M
00 O fO *^
cs oo oo ^o
« 8
o o
O <0 «0
«5 o
Sf
2
!3
s s
BOM cs c » M
•*J Q O O '^ O^ ^O
s o' o' M o' o o g\
B ^1
a o M
III
8 o S
T °°. 1"
\f> ^t -^ "if
<N O w •*
to ON fO
I
336
,4
a*
5
<N 00
o
H
O 00 vO
fN vO
"3
0
VO ro
M <N to rO O
^ "2" Q o TJ- o
r^ vo O r^ 00 O (N
|C ' 8 "
c-
O
O O t^**
o
Cj M O VO* 00* M M |4.
VO TJ-
a
vo 00
M to 00 00 CO
f<5 O *O vO O
»o o" o ' t>. M 6 o 6
3
fj »O
Q rh CS io ON
to g o o ON io
co M g t^ g ^ o
o g g co o o o
to O O O O O O
M O O M o* O O O
o
a
o
00
CO O
o *>. N
.w
M f^ VO IO VO
0 HH M 00 10
o io ro o t^ rf
Q M O ^t" OO O fO O
Meter
M VO IO t^.
o w 1-1 oo 10
O >O rO O l^ rj-
O O vo <N g g Q
w O O O O O O O
3 13
$ II d
<U 4j
C ri
§ &
J3<9 a §
« VN HH 5
01 II 2 6 So
sSl&s
h4 .ti ^ ^ °"
II 5 r< ^ C
*
-
(S <o ,| tS S
C
<s
d
tc
o
§
en
2
d d M
SR
1
*>
c
10 ^
M fO f^ i
M <N W
s
M
o
O O fO
Q
1
O
M 0
§ 8 8 § 2
?o £~
0 0 0 0 M '-
1
§^8 S
£
>>
0 M o 0 M 0 0
2
o-
*«?
«
H
ON
o
W VO »O
o ^> _S
to
«5
St^vO
<N 0
*"* H <^
00
O (N O i-i O
G • \o
h-1 CO Tt"
O O CO ON
cT
'3 ° <N
8
Q M ^^
iyi
W) M II
fa
O O Is* O
^-i
£!} to
r/^
*
O O O O *-i ON O
\^
T^~ o ^
£_,
a
'ft
Q
u:> d g
^
fO
^
""bo
w
<^
ll II »2
. t
t— 1
>
HH
3.8
i— i
cs vo
bi) So
o
i-i to
§10 O
w
N
O cs
M M a*
/*"S>
•S
w O
O 10 M v£> O
D
til
rr1
O O O M rj-vD
0
CO MO
• rt
B w C
W
06
IO M «
*— I M
3
N"
11|
0
w
ft &"J3
fc
10
g
TJ- g) rO
^
?i*J
>
"q M co
c/3
1
ON rO VO
o oo co
C^H
II II II
OO>HOOO»-I^O
CO ^f
oo o
C
o0
II II II
Sr"*
bio
M CO^^
o
cT
M
o o 10 M
o' M' d 1" tA 6
H g»
a
i-i 10 CO t^
O Tt O <N
!w
^
£
O ON fO
o" oo"
o
VO
M *O
a
M' O 00* <O O*.
O cs 1000
O Tt I-I
a
M O O ¥r O5
1-1 O^^o ON
O
'
338
X
a §
10 ON t^ ^ t~»
ON CN IO 00 t>. T^-
HH CO CN M 0 M
00
£
ro
P
IO O <N O O O
o
CN
v> C
r^ co -<t ON co
CO
CN
A 3
•<*• N co r^ CN 10
O M oo O O O
CN
0
CO
C w
• «N o o o o o
o
M
O
M S
li
10 00
O r*^ *O co vO co
CN IO »O M M IO
M
8
s*
O IO CO CO M CN
OO «O
cO
Tf
EV
V
CO ON CN vo ON
ON
Q
CN
T*H Q
O M M CN ^t
CO
CN
t***
c Jj
to' CN IO M O M
0
{->.
vO
CO M
G
||
% 3-^ S? ?
ON
CO
%
O
O rj- O CN *•• CN
O
S
M
Is
(N CO
M co ON ON
M
i—,
CO
85
IF
~ £
t^ M CN M O O
0
co
M
§3 £?|
vO
O
CO
5
$" *
CN 0 M 0 0 0
0
0
X
00 VO rj- CO
CN t^ CN "sT
S V CJ
ON 10 CN TJ-
M
CO
o
§ P« fl
VO M vo O O O
O
t^
CO
O
° 5f *
co co VO Tj- OO
VO co CO ^ CN
o n- o o o
0
1
1
* &"
M O O O O O
o
o
o
imeter = 14.2232 pounds per
'.2048 pound per square foot.
• square meter = 0.091 gross
OJ
1
II
VH'
3
1
n
£
cu
* I
cn
.• cu
03
1
« o
a -n
cy "S
S -s
a> .C
IH
s s
'•M O^
cu
§
G •
ft
I? H
cu ON
O N
0
VH ,J
CU II
3
<u cu
cu
IH 1 1
03
3 J3
M
£ B
o1 <->
en ^C
U
« g
Ui
CU CU
CU
^ Cti
CU
CU
cn 2
S s
1
o
"S CU
S ft
^
ro tu
^ Pn
cu
IH
cu cn
«H G
? CU
03
rt o
M s
&
%z
H. en •
x-s en >>
JS °Q u! *3
u
cu
1-1 -*2
cu qj
o o ft d
ft
a S
•-H x' en CJ
8
X
cu o ^2 S
o
O Vs*
c^J ft 3 cn
15
fO
^t
&°as
t« N_^- lJ
CN
00 ||
fe ON £ £
o
00 ||
ft *> TJ- S
o
M O
cn 0 - -g
^ >> li S
II
ll 0
Mi
- 1 "I ">
*0
0 cu
§ ft g b^
c
9 *-•
t; si N lr
03 ,d
§ ^
i N i t
J3 O
J3 j_
D^ G
en '**
en Q^
« II & £ g
. cn J5 £
s_ cu
e C 4i ** «
&s
1 *
I
cu a
ft o
"S s
o 2
ft bo
M M
&| n § a
C CL cu .1-1 cn
O So C — cu
-*-• o cu -rj ,d
a s s g
* J£Q
HH 14 t^ ro
339
3 !
2 8
4 o
s§ I
§ a *
& §J 5
a o H
« &
o 9
'* M .
« S g
£° i
^^ &
"5 .ti 5
z 3 8>
s*i
to ^3 .
o H f*
w J
B «
^ c
^ ^
<J •&
t
•z.-z
w s
- =
Calori
er mo
lar wt
gra
.
..£2* ii
> so. il
p o*2 «j
Icl
Name of
gas or vapor
n^OI^-^l-
i/5 04 r» w
»/5\g ON O T>
1---00 1^ LO P)
^^SofofofofofS'SofSSofof •CS'S .' 2 >*S**SS .' ' i .' .' '
N u-j 10 ej q •<*• q i q vq oq q « IN N r-. M . "? 9 • 9 • °! °° 9 N. "°. 9? 9
ON co co o_ «-; ir> o<_ o_ r>- 10 co o_oo_ •<£ i
CO W CN l-OD T- o (S
o -r^roiD <n\o r> cu
8&4M:&*2&S8fc*§a&a •
O. CT* ON co cr\ •«£ 04_ i-«_ n_ 04_ co t~;*O.>O_ O uo .
04 ON*O vOnr^CNOO^f^JNcO^iOOi^O
04 CO 1/5--O 00 ON CO -<3-\O 00 CO Tf
. o
. **>
LO M OOCO^UTJCS
MO -00 • •* ON uS 10^0 00
-^ N "-I iilNPIM
-.ncogN*
d d o' d d d 6 d d 6 o' o' d d d d 6 d d 6 d d d d d d d 6 d d d d d d d
°r S o? ONO" co g' F- •* « oo inx '& 04 \o co o' r^oo o ub «' K i-f 1/5 - vb" F- o>
^x8o8S'S-Mt?Sx?!S-n2-<;2^22-8oT^coKgsoro^8<?2r:3'vS!
ON ON to'o vo ••*• t~»
•^ rr O N 04 O\00 -
t^ t^ 10x0 ^0 uouoiO
t^. if) O^ W ^2 OO OOOO UOC4VO CO^MVO O O^
^ iO c'JOO CO (S GO *O iO ^ r^od vO iO ^J- cf^vC •^•^ffOtOCS »-* C) tOr^'^'>-«o6od ^ 10 M COCO
-*0\r^rOiO
of?,
d d
iS'fti
.coo . . i
•H • • •$
•66 • • "6
00 «^^5 .10
OOOOOOM
o' o' o' • M
:§°v<*
1 ++-}-
++
+++
04 04 M 04 ONX vg >T;cOi-i\O * «*> "-1 •* f*3 "-1 <*5<M OOO O ONOO OO O 00 M rf
d o' o' o' o' M M o« 04 o) d w >-> oi o' M « CM to
•* w o' o' •-
SM ^- 1/5 t^OO 04 M (
04 ON OM-i O4 UO O I
M 00 II 04 « O t^ I
M 10 up\q o< 11 o\ i
M «' p-i d 04" M d >
g23^*«,«,'2=,»o«»SS
a u*o u cfu cJcJcJcfo'u'tj uu'o o
055
'
1st
Pf
o »
r ill
340
- *i C
88|
< §1
O *
S s i
§1 I
£ S "°
^ H fc
*l
4J >
|o
h? tfl
* &
•i*.
S2*e
o6'3
0 ° n
RRJ, ;28 :
+ 1 I
COM
tOO^iOOxNlNNMTtOON -^-00 >iQt-~
CO Q CO IDvO T ^J" ^d" ^"OO O 1/3OO ^fMOCO
OK O O q q - « w -; ro co «s to co co co Tr . . \q \o to
oicococococococococococococotococo « w" 6
. T T "1" T °. N. °J °. M. "*. °J (
M N o" 00 •<9-cOcOcOcocOcOCOcOcOcOtOtOCOcOrOcoi
i-iWTtN^Or^OvO "O^O vOvC\OrOO'OcOt^OO-^-t-i'-iO cO^O N CO
--rtt^N 1-1 lOCONOO OsCOcOcOCOi-i UOO M -^-CS UOOO <-> M •- f>) ^O O CO
, i/-) T}-\O COM r*.iOcOC4OOOOOOOO COOO M co tO t^OO ChMt-»Tt-cO^^O
> M ci Tt" r^-vp 10 u*) 10 10
i::
q q q q q q q q q q q q q q q q q q q q 19 10 • • o o
M cs CO TJ- IO\O t^-CM cO'i'U'iM CS rOcO1^ lO^O T^-tHtHO . .cJcO
• q o • q q q q q q q q q q q q q q q q q q • • q q q q q
. pi M . «' CN co •<*• in\d cs co -*r 10 pj co Ti-yD t-^od cf» O . . M *i M M ei
lOO COCOOOO uorOOOO (OCOOOO COOOOOO lOO O OOOON>-i O UOOO 1O .
oor--CM3Nr-.Tf^ ooo ioio<OMOO^b-^i-ioo^o •'S-N cs r^oo oo r-- to t^ 10
r-.>ococo>ot?.0"-. CM •» f? "? <>•<» <^ M cooq q N rt- ^r « up CTMTJ co >-< co
^- GS oi cl G\vo co»-*od u"5Tj-Moo IOM cfs^o lococor^-r^r^coioc^TJ-r^1^-
AUTHORITIES AND METHODS OF CALCULATION
In column IX the figures given in Hempel's "Gas Analysis," p. 375,
were selected for the fundamental weight of oxygen, nitrogen, hydrogen,
carbonic oxide and air.
The formula used for the conversion to English units is,— grams
per liter at o° C. and 760 mm. -f 0.05922 = pounds per cu. ft. at 60° F.
and 30" pressure. The derivation of the factor employed is
28.316 X 0.0022046 Xso-oo X 492
29.9* X 520
The weights of the compound gases are calculated from these data by
Avogadro's law.
Column IV is calculated by the formula: sp. gr. = ft '
and the figures thus obtained agree with the theoretical formula,
mol. wt.
SP' «r' = -5TiT
Columns V and VI are taken chiefly from Lunge's "Coal Tar and
Ammonia."
Column VII is from Ganot's "Physics," edition 1896, page 445.
Columns X and XXIII are from Julius Thomsen's "Thermo-
chemical Investigations," and his results are translated into English units
in columns XI-XII and XXIV-XXV.
Columns XIII and XVIII are calculated on the assumption that
air == 20.9% oxygen + 79.1% nitrogen by volume.
air = 23.13% oxygen -f- 76.87% nitrogen by weight.
Comparison of Degrees Baume with Specific Gravity, American Standard,
for Liquids Lighter than Water. Sp. gr. ± , at 60° F.
1.30 -f- B
Deg.
Baum6
Specific gravity
o.o
O.I
O.2
0.3
0.4
o.5
0.6
0.7
0.8
0.9
10
ii
12
I.OOOO
0.9929
0.9859
0-9993
0.9922
0.9852
0.9986
0.9915
0.9845
0.9838
0.9972
0.9901
0.9831
0.9964
0.9894
0.9825,
0.9818
0.9950
0.9880
0.9811
0-9943
0.9873
0.9804
0.9936
0.9886
0.9997
13
14
15
0.9790
0.9722
0.9655
0.9783
0.9715
0.9649
0-9777
0.9709
0.9642
0.9770
0.9702
0.9635
0.9763
0.9695
0.9629
0.9756
0.9689
0.9622
0.9749
0.9682
0.9615
0-9743
0.9675
0.9609
0.9736
0.9669
0.9602
0.9729
0.9662
0.9596
16
11
0.9589
0.9524
0-9459
0.9582
0.9517
°-9453
0.9576
0.95II
0.9447
0.9569
0.9505
0.9440
0.9563
0.9498
0.9434
0.9556
0.9492
0.9428
0.9550
0.9485
0.9421
0-9543
0.9479
0.9415
0-9537
0.9472
0.9409
0.9530
0.9466
0.9402
19
2O
21
0.9396
0-9333
0.9272
0,9390
0.9327
0.9265
0-9383
0.9321
0.9259
0.9377
0.9315
0.9253
0-9371
0.9309
0.9247
0.9365
0.9302
0.9241
0.9358
0.9296
0.9235
0.9352
0.9290
0.9229
0.9346
0.9284
0.9223
0.9340
0.9278
0.9217
22
23
24
0.9211
0.9150
0.9091
0.9204
0.9144
0.9085
0.9198
0.9138
0.9079
0.9192
0.9132
0.0073
0.9186
0.9126
0.9067
0.9180
0.9121
0.9061
0.9174
0.9115
0.9056
0.9168
0.9109
0.9050
0.9162
0.9103
0.9044
0.9156
0.9097
0.9038
2?
0.9032
0.8974
0.8917
0.9026
0.8969
0.8912
0.9021
0.8963
0.8906
0.9015
0.8957
0.8900
0.9009
0.8951
0.8895
H
0.8997
0.8940
0.8883
0.8992
0.8934
0.8878
0.8986
0.8929
0.8872
0.8980
0.8923
0.8866
28
29
30
0.8861
0.8805
0.8750
0.8855
0.8799
0.8745
0.8850
0.8794
0.8739
0.8844
0.8788
0.8734
0.8838
0.8783
0.8728
0.8833
0.8777
0.8723
0.8827
0.8772
0.8717
0.8822
0.8766
0.8712
0.8816
0.8761
0.8706
0.8811
0.8755
0.8701
31
32
33
0.8696
0.8642
0.8589
0.8690
0.8637
0.8584
0.8685
0.8631
0.8578
0.8679
0.8626
0.8573
0.8674
0.8621
0.8568
0.8669
0.8615
0.8563
0.8663
0.8610
0.8557
0.8658
0.8605
0.8552
0.8653
0.8600
0.8547
0.8647
0.8594
0.8542
34
35
36
0.8537
0.8485
0.8434
0.8531
0.8480
0.8429
0.8526
0.8475
0.8424
0.8521
0.8469
0.8418
0.8516
0.8464
0.8413
0.8511
0.8459
0.8408
0.8505
0.8454
0.8403
0.8500
0.8449
0.8398
0.8495
0.8444
0.8393
0.8490
0.8439
0.8388
i
39
0.8383
0.8333
0.8284
0.8378
0.8328
0.8279
0.8373
0.8323
0.8274
0.8368
0.8318
0.8269
0.8363
0.8314
0.8264
0.8358
0.8309
0.8260
0.8353
0.8304
0.8255
0.8348
0.8299
0.8250
0.8343
0.8294
8.8245
0.8338
0.8289
0.8240
40
4i
42
0.8235
0.8187
0.8140
0.8230
0.8182
0.8135
0.8226
0.8178
0.8130
0.8221
0.8173
0.8125
0.8216
0.8168
0.8121
0.8211
0.8163
0.8116
0.8206
0.8159
0.8111
0.8202
0.8154
0.8107
0.8197
0.8149
0.8102
0.8192
0.8144
0.8097
43
44
45
0.8092
0.8046
0.8000
5.8088
0.8041
0-7995
0.8083
0.8037
0.7991
0.8078
0.8032
0.7986
0.8074
0.8028
0.7982
0.8069
0.8023
0.7977
0.8065
0.8018
0.7973
0.8060
0.8014
0.7968
0.8055
0.8009
0.7964
0.8051
0.8005
0-7959
46
%
0.7955
0.7910
0.7865
0.7950
0.7905
0.7861
0.7946
0.7901
0.7856
0.7941
0.7896
0.7852
0.7937
0.7892
0.7848
0.7832
0.7887
0.7843
0.7928
0.7883
0.7839
0.7923
0.7878
0.7834
0.7919
0.7874
0.7830
0.7914
0.7870
0.7826
49
50
51
0.7821
0.7778
0.7735
0.7817
0.7773
0.7731
0.7812
0.7769
0.7726
0.7808
0.7765
0.7722
0.7804
0.7761
0.7718
0.7799
0.7756
0.7713
0-7795
0.7752
0.7709
0.7791
0.7748
0.7705
0.7786
0-7743
0.7701
0.7782
0-7739
0.7697
52
53
54
0.7692
0.7650
0.7609
0.7688
0.7646
0-7605
0.7684
0.7642
0.7600
0.7680
0.7638
0.7596
0.7675
0.7634
0.7592
0.7671
0.7629
0.7588
0.7667
0.7625
0.7584
0.7663
0.7621
0.7580
0.7659
0.7617
0.7576
0.7654
0.7613
0.7572
57
0.7568
0.7527
0.7487
0.7563
0.7523
0.7483
0-7559
0.7519
0.7479
0-7555
0.7515
0-7475
0.7551
0.7511
0.7471
0-7547
0.7507
0.7467
0-7543
0.7503
0.7463
0-7539
0.7500
0-7459
0-7535
0-7495
0-7455
o.753i
0.7491
0-7451
58
59
60
0-7447
0.7407
0.7368
0-7443
0.7403
0.7365
0-7439
0.7400
0.7361
0-7435
0.7396
0.7357
0.7431
0.7392
0-7353
0.7427
0.7388
0-7349
0.7423
0.7384
0.7345
0.7419
0.7380
o.734i
0.7415
0.7376
0.7338
0.7411
0.7372
0.7334
61
62
63
0.7330
0.7292
0.7254
0.7326
0.7288
0.7250
0.7322
0.7284
0.7246
0.7318
0.7280
0.7243
0.7315
0.7277
0.7239
0.7311
0.7273
0.7235
0.7307
0.7269
0.7231
0.7303
0.7265
0.7228
0.7209
0.7261
0.7224
0.7295
0.7258
0.7220
64
65
66
0.7216
0.7179
0.7143
0.7213
0.7176
0.7139
0.7209
0.7172
0.7136
0.7205
0.7168
0.7132
0.7202
0.7165
0.7128
0.7198
0.7161
0.7125
0.7194
o.7i57
0.7121
0.7191
0.7154
0.7117
0.7187
0.7150
0.7114
0.7183
0.7147
0.7110
67
68
69
0.7107
0.7071
0.7035
0.7103
0.7067
0.7032
0.7099
0.7064
0.7028
0.7096
0.7060
0.7025
0.7092
0.7056
0.7021
0.7089
0.7053
0.7018
0.7085
0.7049
0.7014
0.7081
0.7046
0.7011
0.7078
0.7042
0.7007
0.7074
0.7039
0.7004
70
7i
72
0.7000
0.6965
0.6931
0.6997
0.6962
0.6927
0.6995
0.6958
0.6924
0.6990
0.6955
0.6920
0.6986
0.6951
0.6917
0.6983
0.6948
0.6914
0.6979
0.6944
0.6910
0.6976
0.6941
0.6907
0.6972
0.6938
0.6903
0.6969
0.6934
0.6900
73
74
75
0.6897
0.6863
0.6829
0.6893
0.6859
0.6826
0.6890
0.6856
0.6823
0.6886
0.6853
0.6819
0.6883
0.6849
0.6816
0.6880
0.6846
0.6813
06876
0.6843
0.6809
0.6873
0.6839
0.6806
0.6869
0.6836
0.6803
0.6866
0.6833
0.6799
76
77
78
0.6796
0.6763
0.6731
0.6793
0.6760
0.6728
0.6790
0.6757
0.6724
0.6786
0.6753
0.6721
0.6783
0.6750
0.6718
0.6780
0.6747
o 6715
0.6776
0.6744
0.6711
0.6773
0.6740
0.6708
0.6770
0.6737
0.6705
0.6767
0.6734
0.6702
79
80
0.6699
0.6667
0.6695
0.6692
0.6689
0.6686
0.6683
0.6679
0.6676
0.6673
0.6670
CONVERSION TABLE FOR CONVERTING BaSO4 TO SULPHUR.
Mgs. of
BaSO4
Milligrams of Sulphur
0.0
O.I
O.2
o.3
0.4
0-5
0.6
0.7
08
0.9
p
i
2
o.oo
0.14
0.28
O.OI
0.15
.29
0.02
0.17
0.30
0.03
0.18
0.32
0.04
0.19
0.33
0.06
0.21
0.34
0.08
0.22
0.36
O.OIO
0.23
0-37
O.OI I
0.25
0.39
0.012
0.26
0.40
3
4
5
0.41
0-55
0.68
•43
.56
.70
0.44
0.58
0.72
0-45
0-59
0-73
0.47
0.60
0.74
0.48
0.62
0.76
0.49
0.63
o.77
0.51
0.65
0.78
0.52
0.66
0.80
0-53
0.67
0.81
6
7
8
0.82
0.96
1. 10
.84
.98
.11
0.85
0.99
• 13
0.86
1. 00
• 14
0.88
1. 02
1.16
0.89
1.03
1. 17
0.91
1.04
1.18
O.Q2
1. 06
1.20
0-93
1.07
1. 21
o-95
1.09
•23
9
10
it
1.24
1-37
I-51
•25
•39
•53
.27
.40
•54
.28
•42
•55
1.29
1-43
1-57
I-3I
1.44
1.58
1.32
1.46
1-59
1-33
1-47
1.61
1-35
1.49
1.62
•36
•50
.64
12
13
14
1.65
1.79
1.92
.66
.80
1.94
.68
.81
1-95
•69
•83
1.97
1.70
1.84
1.08
1.72
1.86
1.99
1-73
1.87
2.01
1-75
1.88
2.02
1.76
1.90
2.03
•77
•9i
2.05
15
17
2.06
2.20
2.34
2.08
2.21
2-35
2.09
2.23
2-37
2.10
2.24
2.38
2.12
2.26
2-39
2.13
2.27
2.41
2.15
2.28
2.42
2.l6
2-30
2.44
2.17
2.31
2-45
2.19
2.32
2.46
18
19
20
2.48
2.61
2.75
2.49
2.63
2.77
2.51
2.64
2.78
2.52
2.66
2-79
2.53
2.67
2.81
IS
2.82
2.56
2.70
2.84
2.57
2.71
2.85
2-59
2-73
2.86
2.60
2-74
2.88
21
22
23
2.89
3.03
3.16
2.90
3-04
3-i8
2.92
3-06
3J9
2-93
3-07
3-21
2.95
3.08
3.22
2.96
3-10
3-23
2-97
3-ii
- 3-25
2.99
3.12
3.26
3.00
3-14
3-27
3-oi
3-15
3-29
24
II
3-30
3-44
3-58
3-12
3.45
3-59
3-33
3-47
3-6i
3-34
3.48
3-62
3.36
3-49
3-63
3-37
3-51
3.65
3-39
m
3.40
3-54
3.67
3-41
3-55
3-69
3-43
3.56
3-70
3
29
3-71
3.85
3-99
3-73
3-87
4.00
3-74
3-88
4.02
3.76
3.89
4-03
3-77
3.9i
4-05
3-78
3-92
4.06
3-80
3-94
4.07
3-8i
3-95
4.09
3-82
3.96
4.10
3-84
3.98
4.11
30
3i
32
4.13
4.26
4-40
' 4-14
4.28
4.41
4-15
4.29
4-43
4-17
4-30
4-44
4.18
4-32
4.46
4.19
4-33
4-47
4.21
4.22
4-36
4-50
4.24
4-37
4-51
4-25
4-39
4-52
33
34
35
4-54
4.68
4.81
4.83
4-57
4.70
4.84
4.58
4.72
4.86
4-59
4-73
4.87
4.61
4-75
4.88
4.62
4.76
4.90
4-63
4-77
4-91
4-65
4-79
4-92
4.66
4.80
4-94
36
y
4-95
5-09
5-23
4-97
5-10
5-24
4.98
5-12
5-26
4-99
5-13
5-27
5-01
5-15
5.28
5-02
5.16
5.30
5-03
5-17
5-31
5-05
5-19
5-33
5-06
5-20
5-34
5.08
5-22
5-35
39
40
4i
5-37
5-50
5-64
5.38
£S
5-39
5-53
567
5-41
1!
5-42
5-56
5-70
5-44
5-57
5-71
5-45
559
5-72
5-46
5-60
5-74
5.48
5.61
5-75
5-49
5.63
5-77
42
43
44
5-78
5-92
6.05
5-79
5-93
6.07
5-8i
5-94
6.08
5-82
5.96
6.09
5-83
5-97
6.11
5.85
5.98
6.12
5-86
6.00
6.14
5-87
6.01
6.15
5-89
6.03
6.16
5-90
6.04
6.18
9
47
6.19
6.33
6.47
6.20
6.34
6.48
6.22
6.36
6.49
6.23
6.37
6.51
6.26
6.38
6.52
6.26
6.40
6.53
6.27
6.41
6.55
6.29
6.42
6.56
6.30
6.44
6.58
6.31
6.45
6-59
48
49
50
6.60
6.74
6.88
6.62
6.75
6.89
6.63
6.77-
6.90
6.64
6.78
6.92
6.66
6.80
6-93
6.67
6.81
6.94
6.69
6.82
6.96
6.70
6.84
6.97
6.71
6.85
6.99
6.73
6.86
7.00
5i
52
53
7.01
7-15
7.29
7-03
7.16
7.30
7.04
7.18
7-3i
7-05
7.19
7.33
7.07
7.20
7-34
y.o8
7.22
7.36
7.10
7-23
7-37
7.11
7-25
7.38
7.12
7.26
7.40
7.14
7.27
7-41
54
n
g
7-44
7.58
7.71
7.45
7-59
7-73
7-47
7.60
7.74
7.48
7.62
7.76
7-49
7.63
7-77
7-51
m
7.8o
7-54
7.67
7.81
j'te
il
59
8.12
7.85
7-99
8.13
7.87
8.01
8.14
7.88
8.02
8.15
7.89
8.03
8.17
7.91
8.05
8.19
7.92
8.06
8.20
7-94
8.08
8.21
7-95
8.09
8.23
7.96
8.10
8.24
60
61
62
8.26
8.39
8-53
8.27-
8.41
8.55
8.28
8.42
8.56
8.30
8.43
8.57
8.31
8.45
8-59
8.32
8.46
8.60
8.34
8.48
8.61
8-35
8.49
8.63
8-37
8,50
8.64
8.38
8.51
8.66
8
65
8.67
8.81
S.QS
8.68
8.82
8.96
8.70
8.84
8-97
8.71
8.85
8.99
8.73
8.86
Q.OO
8.74
8.88
9.02
8.75
8.89
9-03
8.77
8.90
9.04
8.78
8.92
9.06
8.79
8-93
9.07
66
67
68
9.09
9.22
9.36
9.10
9.24
9.38
9.11
9-25
9-39
9-13
9.27
9.40
9.14
9.28
9.42
9-15
9.29
9-43
9.17
9-31
9-45
9.18
9-32
9.46
9.20
9-33
9 47
9.21
9-35
9-49
69
70
7i
72
9-50
9-63
9-77
9.91
9-52
9.64
9.78
9.92
9-53
9.66
9.80
9-93
9-54
9.67
9.81
9-95
9-57
9.68
9-82
9.96
9-57
9.70
9-84
9.98
9-59
9.71
9.85
9-99
6.60
9-73 •
9.86
10.00
9.61
9-74
9.88
10.02
9.62
9-75
9.89
10.03
344
CURVE FDR CALCULATING LJLL AEE5 OF
CYLINDRICAL TANK5 WITH CURVED HEADS
IN HDRIZDNTALFD5ITIDN.
ft
h
ls<
s
U
3
it 2t
»/j
o
n
z
25 JO
•4-0 AJ
345
INTERNATIONAL ATOMIC WEIGHTS.
Revision of 1915
As Published by the American Chemical Society.
Name of element
Symbol
Atomic
Weight
Name of element
Symbol
Atomic
Weight
Al
Sb
A
As
Ba
Bi
B
Br
Cd
Cs
Ca
C
Ce
Cl
Cr
Co
Cb
Cu
&
Eu
F
Gd
Ga
Ge
Gl
Au
He
Ho
H
In
I
Ir
Fe
Kr
La
Pb
Li
Lu
Mg
Mn
Hg
Mo
27.1
IO2.2
39.88
74.96
137-37
208.0
II.O
79.92
112.40
40.07
I32.8I
12. OO
14025
3546
52.0
58.97
93-5
63.57
162.5
167.7
152.0
19.0
157.3
69.9
72.5
9.i
197.2
3-99
163.5
i. 008
114.8
126.92
I93-1
55.84
82.92
139.0
207.10
6.94
174.0
24.32
54-93
200.6
96.0
Nd
Ne
Ni
Nt
N
Os
O
Pd
P
Pt
K
Pr
Ra
Rh
Rb
Ru
Sa
Sc
Se
Si
Ag
Na
Sr
S
Ta
Te
Tb
Tl
Th
Tm
Sn
Ti.
W
U
V
Xe
Yb
Yt
Zn
Zr
144-3
20. 2
58.68
222.4
14.01
I90.9
16.00
106.7
31.04
195-2
39- 10
140.6
226.4
102.9
8545 .
101.7
150.4
44.1
79.2
28.3
107.88
23.00
87.63
32.07
181.5
127.5
159-2
204.0
2324
168.5
119.0
48.1
184.0
238.5
51-0
130.2
172.0
89.0
65.37
90.6
Nickel •
Niton (Radium
Praseodymium ....
Rhodium
Pnhalt
Ruthenium
Scandium
Silver •
Sulfur
Pnlrl
Tellurium
Terbium
Thallium
Thulium
Tin
Lanthanum
T pad
Ytterbium (Neoyt-
terbium
Yttrium
Zinc
INDEX.
A
ACID PAGE
in oils 230
in tar 199-205
carbonic, in air 243
carbonic, in boiler scale 240
carbonic, in gas 120
AIR
composition of volume and weight 341
determination of carbon monoxide in (see Gas Analysis)
determination of carbon dioxide in 243
ALKALIES
in ash 224
in cement 272
in fire-clay 224
in water 215
alkalinity of boiler water 214
ALUMINUM
in boiler water 214
in bolier scale 214
in fire-brick 223
in fire-clay 223
AMMONIA
in concentrated liquor 133
in gas 167
in weak liquor 133
in waste liquor 133
AMMONIUM SULPHATE
analysis of 152
impurities in 153
free acid in 152
ASBESTOS
analysis of (see Refractories)
ASH
general analysis 42
determination of, in coke and coal 17-30
ATOMIC WEIGHTS
table of 345
B
BABBITT METAL
analysis of 238
347
BAUME HYDROMETER TABLE
correspondence with specific gravity ....................... 342
correction table ........................................... 236
BEARING METAL
analysis of ............................................... 238
BENZENE
in gas .................................................... 79
in tar .................................................... 197
in drip oil ................................................. 186
analysis of commercial product ............................ 180
BENZOL (see Benzene)
BOILER
scale, analysis of ........................................ ' . . 213
water, analysis of ......................................... 213
BOILING POINT
determination of .......................................... 53
BROMINE NUMBER
determination of ......................................... 44
BRONZE (see Bearing Metal)
C
CALCIUM OXIDE
in lime ................................................... 239
CALORIFIC VALUE
determination of, in coal ................................... 30
determination of, in coke .................................. 30
determination of, in gas ................................... 112
determination of, in oil .................................... 30
determination of, in tar (see Oil)
CARBON
determination of, in steel .................................. 273
fixed, determination of, in coal and coke ................... 17
free, determination of, in tar .............................. 197
total, determination of, in iron and steel .................... 273
CARBONATES
determination of, in boiler scale (see Lime)
determination of, in lime .................................. 240
determination of, in water (see Water Analysis)
CARBONIC ACID (see Carbon Dioxide)
CARBON DIOXIDE
in air .................................................... 243
in furnace gases .......................................... 120
in illuminating gas ........................................ 84
CARBON DISULPHIDE
in gas .................................................... 1 78
348
CEMENT PAGE
general 243
analysis of 270
testing of 244
CHIMNEY GASES (see Fuel Gases)
CHLORINE
determination of, in water 214
CHROMIUM
determination of, in steel 297-306-321-324
Cl,AY (FlRE)
analysis of 221
CO2 (see Carbon Dioxide)
COAL
analysis of 3
determination of nitrogen 28
determination of oxygen 29
elementary or ultimate analysis 24
heating value, determination of 30
proximate analysis of 12
determination of sulphur 18
COKE
analysis of (see Coal)
shatter test 37
COLD TEST OE OILS 237
COMBUSTIBLE GASES
heating value 112
CONGEALING TEST (see Cold Test)
CONVERSION TABLE
metric to English 335-336-337
chemical 328-329
COPPER
determination of, in alloys 238
in steel 294
CYANOGEN
in coal gas 177
in spent oxide 156
in cyanide mud 156
D
DEAD Oil,
analysis of (see Tar products)
349
DISTILLATION PAGE
method for creosote oil 200
method for drip oil 186
method for gas oil 46
method for tar 193
DRIP Oily
analysis of 186
DEW POINT OF GAS
determination of 126
E
ENGLER VISCOSIMETER
description and use 233
ETHYLENE
determination of, in gaseous mixtures 86
ETHANE
determination of, in gaseous mixtures 86
F
FATS AND FATTY ACIDS IN LUBRICATING OIL
determination of 230
FERRIC OXIDE
analysis of new 59
analysis of spent 65
FIRE SAND (see Fire-Clay )
FIXED AMMONIA
determination of 145
FIXED CARBON
determination of, in coal and coke 17
FLASH AND FIRE TESTS OF OILS
methods of determination, gas oil 48
lubricating oil 233
FLUE GASES (see Furnace Gases)
FOULING TEST FOR PURIFYING OXIDE
method 63
FUEL OIL
analysis of 42
heating value of 30
FURNACE GASES
analysis of 120
23
350
GAS PAGE
general properties table 339
analysis of coal and water gas by U. G. I. modification of
Hempel's apparatus 71
Elliot apparatus 89
Morehead apparatus 96
analysis of flue gas 120
cyanogen in gas 177
ammonia in gas 167
hydrogen sulphide, determination of 160
sulphur, total determination of by Referee test apparatus... 169
calorimeter, Junkers 112
factors 334
naphthalene in 173
carbon disulphide 1 78
GASES AND VAPORS
table of constants 339
GAS Oil,
analysis of 42
heating value 52
H
HARDNESS OF WATER
determination 213
HEATING VALUE OF COAL
determination in calorimeter 30
determination of gas 112
determination of oil 30
HYDROGEN
determination of, in coal and coke 24
determination of, in gases 88-123
HYDROGEN SULPHIDE
determination of, in gas 160
HYGROMETER
use of 126
I
IRON
oxide, analysis of 59
oxide (sponge) , analysis of 59
IRON CARBONYL
determination of, in gas 179
K
KJEU)AHI/S METHOD PAGE
for the determination of nitrogen 28
L
LEAD
in bearing metal 239
in bronze and brass 239
in Babbitt metal ' . 238
in solder 238
LIGHT On,
analysis of 199
LIME
determination of, in boiler scale (see Water Analysis)
determination of, in boiler water 215
analysis of 240
LUBRICATING OILS
analysis of 228
M
MAGNESIA
in lime 243
in cement 272
in refractories 224
in water 215
MANGANESE
in iron and steel 281-302
MARSH GAS
determination of 86
METHANE (see Marsh Gas)
METRIC SYSTEM
tables of English equivalents 335~33O-337
MIDDLE OILS
analysis of (see Tar Oils)
MOISTURE
in coal and coke 12
in oxides 60
MOLECULAR WEIGHT
determination of 53
352
N
NAPHTHALENE PAGE
in gas 173
in tar 186-199
melting point of 211
NICKEL
in steel 295-300
NITROGEN
in coal and coke 28
O
OILS
creosote 200
gas 42
lubricating 228
tar 199
OLIFIANT GAS (see Ethylene)
OXIDE FOR GAS PURIFICATION
analysis of 59
fouling test 63
OXYGEN
in flue gas 123-124
in illuminating gas 85
in coal 24
P
PAINT
analysis of 217
PHENOL
in tar 199
PHOSPHORUS
in iron and steel 284-312
in coal and coke 24
PIGMENTS
analysis of, in paint 217
R
REFEREE TEST
description of method and apparatus 169
REFRACTIVE INDEX
determination in oils 52
REFRACTORIES
analysis of 221
353
S
SAMPLING PAGE
coal and coke 4-8
gas 71
oxide 65
tar 130
SILICA
in iron and steel 292
in refractories 222
in water 214
SOLDER
analysis of 237
SOLIDS, TOTAL
in water 213
SPECIFIC GRAVITY
of coke 38
of gases in
of oils 56-137-205
STEEL
analysis of 273
SULPHATES
in water 215
in boiler scale (see Water Analysis)
SULPHUR
in coal and coke 18
in oil 57
in gas 169
in iron and steel 288
free, in spent oxide 67
total, in spent oxide 66
SULPHURETED HYDROGEN
in gas 160
T
TABLES
atomic weights 345
calculating water analysis 328
conversion of barium sulphate to sulphur 343
conversion of English to metric 335~33^-337
conversion of specific gravity to Baume 342
conversion of elements to compounds 329
curve for calculating ullages of tanks 344
354
TAR PAGE
analysis of 130
acids 200
free carbon in 197
in spent oxide 67
water in 132-190
TIN
in bearing metal 239
in bronze 239
in solder 237
TITANIUM
in fire-brick 225
V
VANADIUM
in steel - 317-325
W
WATER
boiler, analysis of 213
estimation of, in tar 132-190
Z
ZINC
determination of, in brass 239
THIS BOOK IS DUE ON THE LAST DATE
STAMPED BELOW
AN INITIAL FINE OF 25 CENTS
WILL BE ASSESSED FOR FAILURE TO RETURN
THIS BOOK ON THE DATE DUE. THE PENALTY
WILL INCREASE TO SO CENTS ON THE FOURTH
DAY AND TO $1.OO ON THE SEVENTH DAY
OVERDUE.
Off: j-r «
DO^
' • 1
wo
DEC tOT33£
MAY 18 19-
8
t
aOAug'eovr
„ .wD -^
H»- -w
r C ^
stvs »
epi'lT ON \l L
JAN 1 *t 1938
U. C. BERKELEY
LD 21-100m-8,'34
UNIVERSITY OF CALIFORNIA LIBRARY
Live Music Archive
Librivox Free Audio
Metropolitan Museum
Cleveland Museum of Art
Internet Arcade
Console Living Room
Books to Borrow
Open Library
TV News
Understanding 9/11