Steffens' process is used, the best stone is dependent both
upon the salts in the molasses and the time it takes for
the lime to slake, which is burned from the stone.
73. Lime may be analyzed according- to the method
g-iven for limestone. If any sulphuric acid is present it
is combined with calcium oxide. The carbonic acid is
combined with mag-nesium oxide, and the excess with
calcium oxide. The remaining- calcium oxide is recorded
as lime.
CHAPTER X.
COAL, COKE, AND FUEL OIL.
74. Coal* The estimation of moisture, coke and
volatile matters, and ash are required in coal analysis.
To determine the moisture weigh out 10 gr of a powdered
average sample and heat at 110-115C for one hour.
This is a sufficient length of time to drive off all the
water, and in a longer heating there is danger of the
sample gaining in weight by the oxidation of sulphides
and hydrocarbons. (PRESENIUS.) Cool in a dessicator
and weigh. The loss is moisture.
Take 1-10 of the dried coal (representing l r of the
original sample) and burn over an exceedingly hot flame
until all carbonaceous matter is consumed and the ash is
white or reddish colored. Cool in a dessicator and
weigh. The loss is put down as coke and volatile mat-
ters and the remainder is ash. The complete analysis
is figured as follows:
Weight of dish and coal 36.282gr
Weight of dish ' 26.282gr
Coal taken lO.OOOgr
Dish and coal before drying 36 . 2828 r
Dish and coal after drying 36.222gr
Water lost 060gr
.060 ~ 10 x 100 = .60 per cent, mosture.
10gr_ .060gr = 9. 940gr remaining, 1-10 of 9.94gr = .994gr.
Weight of crucible and coal 15 . 337gr
Weight of crucible 14.343gr
Coal taken . 994gr
COAL, COKE AND FUEL OIL. 115
Weight of crucible and coal before burning 15.337 r
Weight of crucible and ash after burning 14.3968 r
Coke and volatile matters lost 941gr
.941 -f- 1 x 100 = 94. 1, per cent, coke and volatile matters.
Weight of crucible and ash 14.3%gr
Weight of crucible 14.343*r
Weight of ash 053S r
. 053 -: 1 x 100 = 5 3, per cent. ash.
Resume :
Moisture 60
Coke and volatile matters 94 . 10
Ash.. 5.30
100.00
75. Coke is tested the same as coal, except-
ing- that about 30 gr should, be used for the moisture
test, and it may be dried at a hig-her tempera-
ture, 140C, and only half a gr is used for the
ash. 100 per cent., minus the sum -of the water
and ash, is called the "combustible matter,"
instead of "coke and volatile matters," as
above.
76. Fuel OH. The most important and
most usual test of oil is the determination of its
specific gravity. This is done with*jBeaume's
hydrometer for liquids lig-hter than water (Pig*.
45), the reading- of the hydrometer being- com- Fig. 45.
n6
COAL, COKE AND FUEL OIL.
pared with the corresponding- specific gravity by use
of the following- table :
TABLE B.
Comparison of Degrees on the Beaume Hydrominor Spindle with
Specific Gravity.
Degree .
Sp. G.
Degree .
Sp. G.
Degree.
Sp. G.
Degree
Sp. G.
10
1 000
24
.913
38
.839
52
.777
11
.993
25
.907
39
.834
53
773
12
.986
26
.901
40
.830
54
.768
13
.980
27
.896
41
825
55
.764
14
973
28
.890
42
820
56
.760
15
.967
29
.885
43
.816
57
.757
16
.960
30
.880
44
811
58
.753
17
.954
31
874
45
807
59
.749
18
948
32
.869
46
.802
60
.745
19
.942
33
.864
47
.798
65
726
20
.936
34
.859
48
.794
70
.709
21
.930
35
.854
49
.789
80
.676
22
.924
36
.849
50
.785
90
.646
23
.918
37
.844
51
.781
100
619
The above table is calculated for a temperature of
15C. or 59P., and all observations should be made at
this temperature. However, a difference of 2 Farenheit
degrees either way does not introduce an error of con-
sequence.
The specific gravity may also be taken with a
pycnometer, a specific gravity hydrometer, or any of the
specific gravity balances for liquids. The Beaume
hydrometer is preferable to other methods in the fact
that it is g-enerally used in oil commerce.
Water is so seldom present in oil that it is determined
only qualitatively. A quantity of oil of known specific
gravity is poured over fused calcium chloride, which may
be contained in a basket of wire screen. The specific
gravity of the treated oil is then taken, and if it is less
COAL, COKE AND FUEL OIL. 117
than before, water was present and was taken up by the
calcium chloride. A simpler method, but one requiring
more time, is to fill a glass tube (about 3-16 of an inch
in diameter and 12 inches long) with the oil, having one
end closed. By standing the tube on the closed end, if
any water is present it will separate from the oil in a few
days and go to the bottom.
Ashes. Evaporate 5 gr of the oil in a porcelain dish
until it is sufficiently dry for ignition. This may be
done first on a water bath and then on an asbestos plate
over a direct flame. Burn carefully until a completely
incinerated ash is obtained. The weight of the ash re-
maining divided by 5 and multiplied by 100 will give the
per cent.
Example:
Weight of dish and oil 26 . 370gr
Weight of dish 21 . 370*r
Weight of oil used S.OOOgr
Weight of dish and ash 21.373gr
Weight of dish , 21 . 370gr
Weight of ash 003gr
.003-^5= .0006. .0006x100= .06 per cent.
Flash and Fire Test. The temperature at which the
development of inflammable gases begins is called the
flash point of oil, and the degree of temperature where
the oil itself will burn is called the fire-point. Both
may be tested at the same time, as the test for the latter
is only a continuation of the test for the former. These
determinations can be made with sufficiently accurate re-
sults by the simple apparatus mentioned as follows, but
Il8 COAL, COKE AND FUEL OIL.
for absolutely exact determinations the Saybolt or some
other apparatus with electric sparks should be used:
A porcelain crucible holding" about 90 CC is nearly tilled
with the oil and placed on the ring- of a lamp-stand, over
a sheet (4 inches square) of asbestos, about V% of an
inch thick. A chemical Farenheit thermometer, sup-
ported by a clamp above, is inserted in the oil so that the
mercury bulb is just covered. Heat is applied, the flame
being 1 just large enough to cause a rise of 2 or 3 degrees
in temperature a minute. At the end of every minute
after heat is applied a "test-flame" is passed over the
oil. The "test-flame" should be as small as possible,
but a match generally has to be used in sugar factory
laboratories. The temperature degree, when the passing
of the "test-flame" first causes a flash of light, is re-
corded as the flash point, and the degree when the oil
ignites permanently is recorded as the fire point. In
crude petroleum the latter is from 6 to 15 higher than
the former.
CHAPTER XI.
ANALYSIS OF BONEBLACK*.
77. The Outward Appearance of boneblack often in-
dicates its usefulness in sugar manufacture. Well-
burned boneblack should be of a deep black color and
show a faint velvety cracking". If it is sufficiently porous
each broken piece when held to the tongue should pro-
duce a slight suction. If the boneblack is boiled with
caustic potash or caustic sodium and then allowed to
settle, the supernatent fluid should be completely color-
less; a brown coloring is caused by undestroyed organic
substance (glue, gristle).
78. The Analysis of Boneblack generally comprises
determinations of moisture, calcium carbonate, calcium
sulphate, calcium sulphide, organic matter and decolo-
rizing power. The composition of good boneblack is
about as follows:
Moisture 7 per cent
Carbon 7 to 8 "
Sand and Clay : 2 to 4
Calcium Phosphate 70 to 75 ' *
Calcium Carbonate 7 to 8 "
Calcium Sulphate 2 to. 3 "
Phosphates of Iron and Aluminum .5 {t
Magnesium Phosphate 6 to 1 "
79. Moisture. The boneblack is coarsely powdered
and 10* r are dried at 120C. It usually takes several
hours for the sample to become thoroughly dry. The
weight lost is moisture; divided by 10 and multiplied by
100 will give the percentage.
* Adapted from "I^eitfaden fur Zuckerfabrichemiker" by Dr. E. Preuss.
120 ANALYSIS OF BONEBLACK.
80. Carbon, Sand and Clay. Into a porcelain dish
put 10 gr of the finely pulverized sample and add some
water. Then digest with 50 CC of concentrated hydro-
chloric acid, the dish being- covered with a glass plate to
prevent loss by spirting". Filter through a dry filter, the
weight of which is known, and wash with hot water
until the acid reaction of the filtrate has disappeared
(test with litmus paper). The filter and contents are
dried and weighed, the total, minus the weight of the
paper, being carbon, sand and clay, the remaining
constituents of the boneblack having been taken out by
the digestion with acid. After weighing, incinerate in
a tared crucible. The residue is sand and clay, and this
weight subtracted from the weight of the contents of the
filter paper will give the weight of the carbon. The re-
results obtained, divided by 10 and multiplied by 100,
will give the percentage.
The filtrate from the above, made up to a liter, serves
in the determination of calcium sulphate, calcium sul-
phide, oxide of iron and aluminum, lime, magnesia and
phosphoric acid.
81. Calcium Sulphate. Measure off 200 CC of the
above filtrate, corresponding to 2 gr of the original sub-
stance, and heat to nearly boiling point. Add a slight
excess of barium chloride, precipitating barium sulphate,
and filter as in 59. After burning and weighing, the
resulting weight is divided by 2 to give the weight in
l gr , and is then multiplied by the factor .5832 to give the
weight in calcium sulphate. Multiplying by 100 will
give the per cent.
In factories and refineries having "boneblack houses"
the examination of the boneblack as to its contents of
ANALYSIS OF BONEBLACK. 121
calcium sulphate and its removal by treatment with soda
solution is very important. The gypsum strongly in-
fluences the crystallization of sugar and in the re-burn-
ing* of the boneblack leads to considerable losses, the
calcium sulphate being* reduced to calcium sulphide, and
carbon escapes in the form of carbon monoxide gas.
CaSO 4 -H 4C = CaS + 4CO.
The calcium sulphide thus formed has an injurious
effect, as in contact with metals it produces colored com-
binations which lessen the value of the product. There-
fore it is also necessary to determine the calcium sul-
phide.
82. Calcium Sulphide. Place 5* r of the finely pow-
dered sample in a porcelain dish and moisten with water.
The dish is now put on a water bath and lO** of fuming
nitric acid gradually added. Heat for half an hour, fre-
quently stirring-, and then add 10 CC of concentrated hy-
drochloric acid a few drops at a time. The mixture is
heated 20 minutes longer and is stirred as before. By
this means all the sulphur is oxidized and TUCKER pre-
fers the method to all others. At the end of the heating-
dilute to about 100 CC by the addition of water and filter.
Heat the filtrate nearly to boiling and precipitate with
barium chloride, filter, burn, and weigh in the usual
manner. The weight of barium sulphate is divided by 5
to give the weight in l* r and is multiplied by . 1374 and
100 to give the per cent, of sulphur. The per cent, of
the calcium sulphate obtained in the above paragraph
multiplied by .2356 will give the per cent, of sulphur in
the boneblack which is in combination as gypsum, and
this subtracted from the total sulphur as just determined
122 ANALYSIS OF BONEBLACK.
will give the sulphur in combination as calcium sulphide.
Multiply the per cent, sulphur by 2.248 to obtain the per
cent, of calcium sulphide.
83. Sugar Contents. Powder 50 gr and boil with
100 CC of water for 20 minutes. Let the mixture settle
and filter off the clear fluid. Add water to the sediment
and boil again, filtering' as before, and repeat the opera-
tion. The sediment is now placed on the filter and
thoroug-hly washed with boiling water. Evaporate the
combined filtrates to about 75 or SO CC and rinse into a
100-110 CC flask. When cool make up to the mark and
determine the sug-ar volumetrically. The result ob-
tained is divided by 50 as 50^ r were used.
84. Calcium Carbonate. During filtration the bone-
black takes up calcium carbonate from the juices, and
the pores are gradually closed. This excess is removed
down to 7 per cent, (not below this, as it would affect the
calcium phosphate present as a normal constituent) by
washing- the boneblack with hydrochloric acid, and the
amount of acid necessary is calculated from the determi-
nation of calcium carbonate present. In making- this
estimation, Scheibler's apparatus, shown in Fig-. 46, is
g-enerally used. The execution of the analysis is as
follows :
Put the weighed quantity (1.7 gr ) of finely pulverized
boneblack into the developing- bottle A; fill the caout-
chouc cylinder S about half-full with concentrated hy-
drochloric acid (1.12 sp. g.) and place it carefully, with
pincers and without spilling, into the bottle A. Fill by
pressure on the bulb W of Woulff's bottle E (which con-
tains water), the two communicating tubes DandC, with
water, until the fluid in C is at zero, the water in D
OF THK
UNIVERSITY
Fig. 46.
2
ANALYSIS OF BONEBLACK. 125
being 1 on the same level. The pinch-cock q is opened
during the filling, to allow air to escape. Care must be
taken not to overflow any of the water into B. for the
apparatus would have to be taken apart and dried.
Now place the glass stopper, fastened to the rubber
tube r upon the developing* vessel A (greasing* the joint
with tallow), and close the pinch-cock q. Hold the
bottle A at the upper end with two fingers, to avoid
warming it, and incline it so that the hydrochloric acid
is poured over the substance. The carbonic acid devel-
oped rises through r into the rubber bulb K and crowds
out an equivalent amount of air in B which, in turn, re-
duces the water in C- The pinch-cock p is opened,
whenever necessary, to make the level of the fluid in C
and D equal. A is shaken to generate the lost gas and
when no further development occurs, the volume of
water in- C is read and the temperature observed. From
these the percentage of calcium carbonate is determined
by the accompanying Table C.
Example :
The volume of gas generated is 11.2 (see n m Fig.
45) at a temperature of 21. By referring to the table
we find that 11 volumes at 21 is 10.74 and 2 volumes is
1.80. Dividing the latter by 10 gives .18 for the .2 of a
volume. Therefore, the per cent, of CaCO is
10.74 + .18 = 10.92 per cent.
As boneblack often contains caustic lime it is advisa-
ble, before making the analysis as above, to dampen the
sample with ammonium carbonate and evaporate to dry-
ness. An error is introduced when calcium sulphide is
present as sulphuretted hydrogen is developed as well as
carbonic acid. TUCKER avoids this error by adding a
00 M O iO M r-t
~
ON
I
Sj
UJ I
-J *o
OJ
I
a
ANALYSIS OF BONEBLACK. I 27
small amount of copper chloride to the hydrochloric acid
used.
Considering- 7 per cent, as the normal amount of cal-
cium carbonate, the quantity of acid of any strength
necessary to remove the excess may be calculated by the
use of Scheibler's Table D.
Example :
The calcium carbonate obtained in the above sample
is 10.92, an excess of 3. 92 "over the normal 7 per cent.
The amount of acid, say 1.175 sp. g. or 21.5 Beaume,
necessary to reduce this excess is determined by referring
to the table as follows:
3. parts of calcium carbonate = 6.3112 parts of acid.
0.9 " " =1.8934
0.02 " " " = .0409 "
3.92 parts of calcium carbonate = 8.2455 parts of acid.
In a ton of 2,000 Ibs. of boneblack having the above
percentage of CaCO 3 would take
2,000 x 8 2455 per cent. = 164.91 Ibs.
of acid of 1.175 sp. g. to remove the excess.
85. Decolorizing Power. Equal amounts of a mo-
lasses solution are treated, during the same length of
time, with equal parts of a new efficacious char and the
boneblack to be analyzed. From the difference of color
of the two filtered solutions the efficacy of the boneblack
can be approximately determined. Stammer's color in-
strument should be used where frequent analyses of
boneblack are made.
CHAPTER XII.
ANALYSIS OF CHIMNEY GASES.
86. Smoke Gases consist largely of carbonic acid,
oxygen, nitrogen and carbon monoxide gas; marsh gas,
sulphuric acid, etc., are found only in small quantities.
The analysis is most easily made by use of an appa-
ratus which removes each constituent by absorption, the
percentage of each being determined by the diminution
of volume of the sample used. The apparatus most
commonly used is Orsat's, or a modification of it.
87. Preparation of Reagents. Concentrated solu-
tions of caustic potash, pyrogallic acid and copper
chloride are used for the absorption of the most impor-
tant gases carbonic acid, oxygen and carbon monoxide.
The caustic potash solution is made by diluting 1
part of potassium hydrate with 2 parts of water. An
alkaline solution of pyrogallic acid is made by mixing 1
volume of a 25 per cent, solution of pyrogallic acid with
a 60 per cent, solution of potassium hydrate. The solu-
tion for absorbing carbonic oxide is made by shaking a
mixture of equal parts of a saturated ammonium chlo-
ride solution and ammonia with copper shavings, until
the fluid has turned dark blue.
88. Orsat's Apparatus (Fig. 47) consists of a gas
measuring-tube A which, in the lower narrow portion,
has a scale divided into half -cubic centimeters from to
40, and is surrounded by a glass jacket filled with water,
to avoid deviations of temperature. The lower end of
the gas burette A is connected with the aspirator bot-
tle E by a rubber tube. By raising and lowering this
ANALYSIS OF CHIMNEY GASES.
bottle, containing- water, the gas burette can be filled
with water and emptied, thereby drawing- the g-as mix-
ture to A, or pressing- the g-as therein contained into the
upper conduit pipe. The upper portion of A leads into
a giass tube at rig-ht ang-les to it, which has three rests
furnished with the cocks a, b, c; these cocks make corn-
Fig. 47
munication possible with the absorption vessels B, C, D,
each of which is ag-ain connected with a reservoir of like
shape (B', C, D'.)
The absorption vessels are filled with many narrow
tubes of glass, in order to give the absorption liquids as
larg-e a surface as possible. (In the diagram only a few
are denoted to give clearness.) The horizontal tube
previously mentioned has at its end a tube bent like a U
130 ANALYSIS OF CHIMNEY GASES.
(e), the shanks of which are filled with cotton for the
filtration of the smoke gases entering- through f, while
in the curve of the same there is a layer of water. Be-
tween the curve of the horizontal tube and the cock c
there is a Winkler's three-way-cock, by which the tube,
and thereby the entire apparatus, can be connected with
the tube f, leading- to the gas line, as well as with the
air-injector i. The injector is for the purpose of pump-
ing- out the air in the tube f before using the apparatus,
being done by blowing into the mouthpiece g.
89. Execution of the Test. First, the absorption
liquids from the reservoirs in the rear must be brought
to B, C, D, which is done as follows: Close the cocks
a, b, c; fill the burette A with water by placing the
three-way-cock into such a position that A communicates
with the outer air. Lift the bottle C and close the cock
d against the atmosphere; then lower the bottle E again,
open cock a, whereby the water flows from the burette to
E and an air-diluted space is formed in B. The air-
pressure then forces the absorption liquid from the res-
ervoir to B, and a must be closed at the moment when
the fluid reaches exactly to the mark. In the same manner
the vessels C and D are filled. By means of the injector
i the air must be pumped out of the tubes, which is done
in the manner above mentioned. Now, the tube e must
be connected by f with the gas-line and the three-way-
cock must be placed in such a position that the filled
burette A is connected with the atmosphere and the gas-
line. By raising and lowering the bottle E repeatedly,
the burette A and the tubes are rinsed with smoke-gas
until the operator is sure that the air is completely
crowded out.
ANALYSIS OF CHIMNEY GASES. 131
After the water in A is set in again to the mark, the
three-way-cock is turned so that A as well as the g-as-
line is closed ag-ainst the atmosphere and the smoke-g-as
line communicates only with the burette A. By opening-
the pinch-cock in front of E and lowering- the aspirator
bottle, the burette is filled with the g-as to be analyzed to
a little below the mark (100 ccm ). Whereupon the same
is closed ag-ainst the atmosphere and the g-as-line. Now
set in the fluid exactly to the zero point and allow the
excess of pressure to escape into the atmosphere by
opening- once quickly D. The cock a is opened, and by
raising the bottle E, the g-as is pressed into B, which
contains caustic potash. Repeat this operation several
times and finally hold E at such a heig-ht that the level
of the water is equal to the mark on B. Cock a is then
closed and the heig-ht of the liquid in A is read off.
Difference to 100 will give the percentag-e of carbonic
acid in the g-as. In the remainder of the g-as mixture,
determine as above, one after another, the contents of
free oxyg-en and carbon oxide g"as. The g-as volume
which remains is calculated as nitrog-en.
The absorption liquids can be saved from spoiling- by
pouring- some solar oil into the rear reservoirs, thus ex-
cluding- the atmospheric air. If thus protected, the
fluids will suffice for several hundred analyses.
9O. Franke's Gas Burette (Fig-. 48} may also be
used for smoke-g-as analysis. It has an advantag-e over
the Orsat's apparatus, in being- more simple in con-
struction.
The burette consists of the measuring- space M, the
lower cylindric part of which is graduated into whole
and half cubic centimeters, and the space R serving- for
132
ANALYSIS OF CHIMNEY GASES.
holding- the absorption liquids. The connection be-
tween the two can be produced by the glass-cock r, which
has a wide double boring-. The measuring- space M, be-
tween the two cocks m and r, holds ex-
actly lOO 00 " 1 . Into a socket at the
lower end of the space R the glass
cock a can be placed to close it air-
tight.
91. The Execution of the Analysis
with Franke's burette is accomplished
in the following- manner : Fill the bu-
rette completely with water (space M
and R), connect the point b with the
g-as-line and let so much of the g-as
enter that the space R is about half-
filled. Then close the cocks m and r
and remove the water in R, so as to
fill R completely with the absorption
liquid.
In order to exclude the air com-
pletely, pour into R so much of the
reag-ent that even the funnel-shaped
widening- is partly filled with it. Now
" m place the opened cock a carefully into
the socket, so that from the bor-
ing- as well as from the point below
the cock the air is completely excluded.
The excess of the absorption liquid
accumulated in the widening- is poured
Fig. 48. back into the storing - bottle after cock
a is closed.
In order to put the g-as-volume in the measuring-
space under atmospheric pressure, raise for a moment the
ANALYSIS OF CHIMNEY GASES. 133
cock m. The absorption of the constituent to be deter-
mined in the gas mixture is accomplished easily by open-
ing- the cock r, so that the reagent enters into the
opening- space. By shaking the burette, this operation
can be hastened. After this is done, place the burette
on the point a and wait until the absorption liquid has
completely returned into R from the measuring space.
The space R must then be filled again completely to the
boring of the cock r. Now take out the cock a, pour out
the reagent, and replace the same with water, with the
precaution that now, even in the point, no air remains.
The whole burette is now turned with the point a down-
ward, placed into a high cylinder filled with water, and
below water the cocks a and r are opened. On account
of the air-diluted space, produced by the absorption, the
water will now rise to a certain height into the measur-
ing space. The reading off of the percentage contents