Dec., :192o ExP'r. No.
T H E J O U R N A L OF I N D U S T R I A L A N D ENGINEERING CHEMISTRY
....... .. ....
Wt 'sodium oxalate g... Temp. at start of rdn.. Vol catalyst soln used cc.. Vol: KMn04 requ'ired, &. Time for 1 c c . .
TABLEI1 1 062000 70
.. . 0 .. . . . . . . . ...... .. .. 33.90 1 min. (-1 Time for entire titration ..... . . Moderately rapid
2 0.2$00 22.5 0 33.87 4 min. 11 sec. 1 hr. (approx.)
0.2$00 22.5 22.5 5 10 33.85 33.85 1 min. 45 sec.
was taken for the entire titration, and was not so accurately observed as in the preceding experiment. Nevertheless, Table I1 shows a n effect similar t o t h a t already shown.
9 min. 6 min.
CONCLUSION
3 0.2$00
4
30 sec.
masses during the course of t h e process. I n this run the permanganate was added several drops a t a time with constant agitation, as rapidly as the solution cleared, each addition being made while the solution was still faintly pink. The acidity was about I per cent H2S04, but as it was not controlled as carefully as in the preceding case, and as this, as well as the mass of KMn04, affects the rate, the time for these runs
These experiments indicate t h a t the addition of MnS04 solution t o permanganate titrations is a practicable method of increasing reaction velocity, in t h a t the time of the peroxide-permanganate titration can by this means be reduced from about 3 5 min. t o 8 sec., and t h a t of the cold oxalate-permanganate titration from over a n hour t o 6 min. for the entire titration. The use of the catalyst does not affect the accuracy of the end-point.
LABORATORY .AND PLANT THE PRESERVATION OF BAGASSE IN SUGAR-CANE MILL CONTROL1 By Guilford L. Spencer
container. The ammonia thoroughly permeates the bagasse, saturates the acids, and imparts a characteristic yellow color t o the sample. The analysis of the bagasse CUBAN-AMERICAN SUGARCo., 129 FRONT ST., NEW YORK,N . Y. is conducted as usual, except t h a t no sodium carbonate A review in the March 1920 issue of the International need be added in the digestion, and the water extract Sugar Journal, page 169,calls attention t o the deteriora- must be acidulated with acetic acid prior t o clarifition of bagasse composite samples as regards sucrose cation with subacetate of lead. content. I n this review two chemists report decomposiI n comparative tests of finely comminuted bagasse, tion even in the presence of formaldehyde or chloroform, the samples were analyzed immediately, after storage a n d a third chemist's experiments show no loss of sugar with formaldehyde, and after storage with ammonia, after 5 hrs. storage in a stoppered bottle without anti- for periods of 3 and 6 hrs. The formaldehyde sample showed a loss after 3 hrs. and a considerable loss after septic. The writer began the use of formaldehyde as a pre- 6 hrs. The ammonia sample lost 0.1 per cent sucrose servative of samples in the laboratory, and of juices in 6 hrs. The sample originally contained 3 per cent and meladura in the factory in the season of 1903 t o of sucrose. Therefore, formaldehyde is not appar1904 in Cuba. He abandoned its use except for very ently a safe preservative for bagasse. short storage periods for juices (I hr.) and bagasse It is the writer's expectation t o have made many ( 6 hrs.), on account of inversion of sucrose by the comparative tests, using ammonia in preserving plant acids and not on account of ferments. At t h a t bagasse samples, with a view t o arriving a t more time, however, experiments indicated formaldehyde definite information. A combination of ammonia for t o be a fairly safe preservative for bagasse for short saturating the plant acids and a n antiseptic for preperiods. Formaldehyde is extensively used, and is venting fermentation is desirable. ' Preliminary exwithout a rival in t h e protection of juice and meladura, periments indicate t h a t bagasse may be preserved during forced stoppages of the factory, though loss for periods of several hours in a n atmosphere of amby inversion is known t o occur. It is possible t h a t the .monia and chloroform. This is also effective in prepresent very heavy milling with long trains of mills serving filter press-cakes. and with large use of maceration water, as compared with t h e conditions of a few years ago, may be in part THE SPECIFIC HEAT OF PETROLEUM AT DIFFERENT causes of the unsatisfactory results now obtained with TEMPERATURES' formaldehyde. By F. W. Bushong and L. L. Knight I n a.ccopnting for irregularities in bagasse tests, the RESEARCH LABORATORY, GULP REFININGCo., PORTARTHUR, TEXAS writer recefitly found these t o be due t o the inefficiency The work herein described was undertaken t o of formaldehyde in protecting the samples. There was usually no evidence of fermentation, and it is determine the rate of increase in the specific heat probable t h a t the loss of sucrose was due t o inversion. of petroleum with rise in temperature. The apparatus ThiS ked t o renewed experimentation with strong employed was the Parr standard calorimeter, which ammonia, as proposed and practiced in Egypt by the gave results of sufficient accuracy for technical work. The bomb was charged with benzoic acid, as recomlate Henri Pellet. The bagasse is collected in covered cans in a very mended for the standardization of the instrument, strong atmosphere of ammonia. Cotton, saturated and the oil or other liquid under examination was with strong ammonium hydroxide, is placed in per- employed as the calorimeter fluid. forated tin boxes a t the top and bottom of the bagasse 1 Presented before the Division of Industrial and Engineering Chem1 Presented before the Section of Sugar Chemistry at the 60th Meeting of the American Chemical Society, Chicago, Ill., September 6 to 10, 1920.
istry at the 59th Meeting of the American Chemicdl Society, St. Louis, Mo., April 12 to 16, 1920.
