ilugust, 1925
INDUSTRIAL AND ENGINEERING CHEMISTRY
819
Effect of Moisture
Experience on this method of testing clays indicates that it is limited to burned clays. Clays revivified by other mean? do not line up a t all with the percolation data. The effect of water in the clay on the test is also interesting. Although it is general experience that the presence of moisture in clay very materially lowers its decolorizing activity on percolation a t temperatures below the boiling point of water, the methylene blue test is not affected. This is, of course, as would be expected, but the results-as exemplified in the data in Table Ti-are rather striking. Apparently, the methylene blue test indicates the value which the clay would have if it were dry. Inasmuch as samples of clay are much more likely to have an opportunity to absorb moisture than the large bulk of clay from the kilns, this point offers a decided advantage for the methylene blue test, hilice precautions to insure the avoidance of moisture absorption are eliminated. Table V-Effect
of Moisture on M e t h y l e n e B l u e N u m b e r a n d Filter Yield
Clay A
B 1 He#rylubOilfi t e r r a fo'6'iJACoiot
2
--..
800
\
.
io r ; L r i O i i Frltcred to
'2
VPlF
Co1 0 1
1
I
Per cent moisture 0.0 0.18 0.90 3.70
Methylene blue number 0:i 0.8 0.9
0.0 0.12 0.35 7.40
7.0 8.0 8.0 9.0
Filter yields, grams per 600 grams light !ubricating oil filtered to 1 N. P. A. 2 N. P. A. 1130 200 880 160 850 180 475 50 820 100 720 I J 0 510 0 310
Destruction of Muscle Shoals Ammonium Nitrate b y Fire and Explosion' By C.
E. Munroe
SATIOSAL RESEARCH COUNCIL, WASHINGTON. D. C.
R O carloads of ammonium nitrate from Muscle Shoals
IC
Y
5
IO
I
/S
I ZO
J
/ycthyJPne B h c Numbers Variatlon i n Filter Y i e l d s w i t h M e t h y l e n e B l u e Color
the points lie along the same genera1 direction, although they do not conform to any expected form of curve. The curves have been drawn as straight lines only as an approximation to the recorded data. The points on the unused clay are somewhat out of line and if these are taken out amuch smoother curve is possible. T a b l e IV-Comparison
Clay
Methylene blue number
A
0.8
C
E F G I
6.0 7.5 11 15 22
'/2
of Filter Yields w i t h M e t h y l e n e B l u e N u m b e r -FILTER YIELDS(GRAMSPER 600 GRAMS)? Heavy lubricating Light lubricating oil filtered to oil filtered to N. P. A. 1 N. P. A. 2 N. P. A. 6 N. P. A. 1350 2100 75 225 1380 25 112 800 1000 0 69 660 480 620 0 69 435 0 0 365 280 0 0 230
were destroyed by fire while in transportation. One of these fires occurred on Bpril 4 and the other on Mag 3, 1925. Each car contained 220 barrels of the material, it having been packed in new flour barrels lined with manila paper some six years previously. As these barrels, with their contents, had been standing in the warehouses for some six years, and therefore exposed to varying changes in humidity, the barrel staves had become well impregnated with ammonium nitrate, and it is thought that the fires may hal-e been caused by the friction of these niter-impregnated staves upon one another. Other shipments came through successfully, among them two carloads made up elsewhere in the train drawing the car which was destroyed on May 3. On hlay 7 an explosion occurred in the nitrate of ammonia emporating pan of the Hercules Powder Plant, a t Emporium, Pa., whereby one man was killed, another one slightly iiijured, and the shed in which the operation was being conducted demolished. The explosion occurred during the reprocessing of Muscle Shoals ammonium nitrate, while the solution was being evaporated in an open cast-iron pan, fitted with steam coils. Some of the nitrate that was being reworked had been coated and it was thought that sufficient organic matter had accumulated from this source to form a. mixture, which was explosive a t the crystallizing temperature, 276" to 278" F., then being used. It is estimated that from 400 to 500 Bounds of nitrate were involved in the explosion, and that the explosion originated in the "heel" left in the pan. 1
Recei\ ed June 19, 1928.
