INDUSTRIAL A N I ) ENGINEERING CHEXISTRY
May, 1925
this point the CaO content increases rapidly. Thus it is entirely possible to clarify juices with lime and obtain a clear juice of lower CaO content than originally present. Table XI1 pH Raw 7.2 8.85 9.1 9.25 Raw 7.3 8.0 8.3 8.8
(Figures in grams per liter) JUICE-----PRECIPITATE-PnOs MgO CaO Pi06 0.384 0.406 0.191 0.356 o:ib o:i& 0,292 0.289 0,093 0.325 0.297 0.316 0.318 0.087 0.301 0.314 0.317 0.084 0.388 0.388 0.252 0.357 o:iii o:i& 0,190 0.238 0,198 0.348 0.256 0,260 0.132 0,338 0.276 0,292 0.330 0.113
CaO 0.154 0.249 0,251 0.259 0.311 0.219 0.223 0.263 0.258 0.241
MgO
o:Oio
0.081 0.088 0.091
o:&i
0.040 0.049 0.058
Table XI11 gives data on a juice whose reaction TT-as increased in small steps. Table XI11 (Figures in grams per ~-Jc.IcE----OH CaO P ~ O S hfrO DH 7.6 0.357 0.392 Raw 0.180 7.7 0.188 0.355 7 . 0 0.252 7.8 0,180 0.360 7 . 1 0.249 8.0 0.125 0.355 7 . 2 0.239 8.2 0.115 0.348 7 . 3 0.230
liter) ------JcIcE-CaO 0.241 0.241 0.258 0.259 0.267
PzOr 0,099 0.099 0,089 0.062 0.060
hfgO 0.346 0.341 0.341 0.339 0,341
495
influenced, however, by organic acids and especially by adsorbed substances. Cc. N saccharate per liter 1 2
3
4 5 6 7 8 9 10
:f
13 14 15 16
17
--Juice Cold 6.0 6.4 6.5 6.6 6.9 7.0 7.1 7.3 7.4 7.5 7. I 7.9 8.0 8.1 8.3 8.6 9.0
1-
Table XVI -PH VALUES----
--Juice Cold 6.0 6.2 6.4 6.6 6.9 7.0 7.1 7.2 7.3 7.5 7.6 7.8 7.9 8.1 8.3 8.4 8.6
Hot
... 6.2
6.4 6.6_ 6.t
6.8 6 8 6.8 6.9 6.9 7.1 7.2 7.4 7 8 8 0 $ 2 8.6
Table XIV
-
(Pigures in grams per liter) -PRECIPITATEP .~~ ~OT CaO Pi05 DH Raw 0,427 0:031 0: bi8 7.2 0.381 0.083 8.0 0.060 0.356 0,067 0.099 8.8 0.328 9.2 0.198 0.221 0.211 9.4 0.325 0.351 0.102 n.ni4 n 428 9.7 0.390 .. ... 0.008 0.522 0.416 .
---JUICE-
CaO . . 0,225 0.322 0.333 0.349 0.291 0.239
oH ~~
Raw 6.9 7.0 7.1 7.4 7.8
-8 4-
n.. -. 214 .
,
9.0
..
0,259
,-JUICE ONLYCaO P10s 0.187 0.277 0,261 0.271 0.310 0.417 0.420
...
...
Hot 6.0 6.2 6.4 6.6 6.7 6.8 6.9 7.0 7.0 7.0 7.1 7.2 7.3 7.5 7.8 8.1 8.3
Table XT’II shows the relation of pH values in the various steps in clarification in the factory. The data cover a period of 10 hours, sampling every 15 minutes. Excellent clarification was obtained. Table XVII Raw-limed
Table XIS’ shows data on cold juices, clarified without heating.
2-
Juice
No. tests averaged pH values
40
8 42
C1,arjfied juice
79
7.99
Sirup 40 7.82
It is thus evident that the actions taking place in defecation are influenced by so many varying factors that their formulation will be difficult, indeed, if not precluded.
A Distilling Flask for Corrosive Liquids’
With these data a t hand, it remains to correlate them to By Louis Sattler and Bernard R. Mortimer existing laws of equilibrium. This, after a comprehensive review, the writer has been unable to do. It is evident that L UNIVERSITYO F CHICAGO, CHICAGO, I L L . there are disturbing influences. The ratio of CaO to PZOS KENTC H ~ X I C ALABORATORIES, in the precipitates is not constant, but increases as the reaction is increased as shown in Table X. From Table VI the ratios T H E distilling flask is of the Claissen type, but it is so modified that a are in the order, 1.06, 0.86, 0.66, 0.48, 0.42, 0.35. This ratio for the secondary calcium phosphate is 1.127 and for the short thermometer can tertiary salt, 0.83. Uncombined CaO can exist, then, only be hung from a hook in in solid solution in the precipitate. These relations of CaO to the ground stopper by Pz06in dilute solutions have been noted in the 1iterat~re.I~means of a platinum The influence of organic acids is shown in Table XV. So- wire. In order to allow lutions of monosodium phosphate containing 0.74 gram the thermometer to hang PzOS per liter and acid as indicated were brought up to a vertically without touchreaction of pH 8.0, while boiling, with a normal solution of ing the glass, three sharp calcium saccharate. . The analyses refer to the filtrate. depressions are made. The other stopper is holTable XV low, and 0.5-mm. tubing (Figures in grams per liter) is sealed to each end. --TARTARIC-HYDROCHLORIC --CITRIC-Cc. N CaO Acid CaO Acid CaO In this way an inert gas 4 0 0.70 0.057 0.00 0.000 may slowly be bubbled 8 0 1.40 0.169 0.75 0.020 2.10 0.320 1.50 0.211 12 0 into the flask while the 2.25 0.372 ... ... distillation is in progress. The influence of organic acids is thus quite evident and the The side arm is put on contrast with mineral acid sharp. It has long been known with an inner seal to that the precipitation of salts soluble with moderate difficulty, prevent mechanical consuch as phosphates, is rendered more difficult by complex t a m i n a t i o n . S h o r t range t h e r m o m e t e r s ions of organic oxygen derivatives.’4 Data on the buffer action of juice are given in Table XVI. which come in sets of six The boiling juice shows marked buffer action in the range or seven, about 15 cm. -A 6.8 to 7.1, though distinct buffer action is shown over the en- long, are found to be extire range. This buffer action is due primarily to phosphates, cellent for use with the distilling flask. 1 3 Roscoe and Schlorlemmer, “Treatise on Chemistry,” Vol. 11, p. 557. . I .
‘4
Stieglitz, “Qualitative Chemical Analysis,“ Vol. I, p. 239.
1 Received
February 24,1925.
