SAFETY Reducing Fluorinated Compounds W i t h L1AIH4 Causes Explosion Kxtreme caution should be exercised in the reduction of a n y fluorinated compound with lithium aluminum hy dride, according t o Wolf Karo, of Monomer-Polymer, Leominster, Mass. Two incidents occurred in his work with the hydride reductions. In the first, Karo was preparing Nethyl - 1,1 - dihydroperfluorobutylamine on a three-molar scale for the first time by reduction of the corresponding amide with lithium aluminum hydride. Related compounds h a d b e e n pre pared several times by substantially the same method without incident. How ever, on this occasion, a stopper blew out of a standard taper joint; t h e evolv ing solvent ignited. T h e flames were controlled with a carbon dioxide ex tinguisher, but the material in t h e reac tion flask caused a spectacular geyser like evolution of gases for about 20 minutes. In light of this experience, K a r o took additional safety precautions w h e n run ning similar reactions. On another occasion, he prepared 1,1-dihydrotrifluorethylamine; t h e reaction went smoothly and the yield was good. Three weeks later he carried out the same reaction. Since the hydride can b e obtained in 100-gram lots, the scale of reaction was such that a freshly opened c a n could be used up completely in t h e run. After the first fire, he h a d set a limit for glass equipment at this quantity of hydride. The maximum flask size was to b e 5 liters; at least 2 liters of ether to be maintained per 100 grams of reducing agent. Once all t h e ground h y d r i d e h a d been added, t h e flask ( b e h i n d a pro tective shield) was cooled in an icesalt bath until solution h a d b e e n com pleted. Karo then added a solution of 249 grams of trifluoracetamide in 1 liter of anhydrous ether. T h e material was stirred vigorously, nitrogen was passed through the flask, a n d cooling was continued. About two thirds of the amide solution was a d d e d , t h e addi tion was discontinued for a b o u t 15 hr., and the remainder added m u c h as be fore. The mixture, now o p a q u e a n d fight gray in color, was gradually w a r m e d to room temperature by slow addition of water to the ice bath. Stirring was continued at room tem perature for about 1 hr., w h e n small, light-colored platelets were noted in the fluid. Karo bad never observed this phenomenon before. T o bring t h e reaction to completion, the bath temperature was gradually 1368
raised. A sludge began to form at t h e bottom of the flask, interfering with t h e stirring. W h e n the sludge was agi tated by manually turning the stirrer, bubbles rose to the surface of t h e ether, and some reflux occurred. At one point, when the bath t e m perature was still cool t o t h e hand, t h e stirrer stopped again. W h e n Karo tried to start it, an explosion took place, appreciably damaging the laboratory. Karo suffered burns and lacerations from flying glass. He has these suggestions as to h o w it might be possible to operate safely: Before a reduction, treat very small amounts of hydride in ether with a small quantity of t h e c o m p o u n d to be r e d u c e d [C&EN, 2 9 , 3 0 4 2 ( 1 9 5 1 ) ] . After evaporation t o dryness b e h i n d a barricade, heat cautiously on a hot plate. This might indicate which re actions are most dangerous, b u t m a y not exclude all unsafe ones. Carry out t h e reaction on a m u c h smaller scale, at higher dilution, a n d with particular attention to a d d i n g materials in such a way t h a t no sig nificant quantities of u n r e a c t e d m a t e rials accumulate. Keep amides at r e d u c e d pressure in a vacuum desiccator i n t h e presence of phosphorus pentoxide for some t i m e just prior to use. Follow usual precautions suggested b y the hydride manufacturer.
• W o r k - d e a t h total for 1 9 5 4 d r o p p e d to 14,000, a drop of 79fc from the 15,000 workers killed in 1 9 5 3 , according to Bureau of Labor Statistics. This is the low for the 18 years for which rec ords are available. Total of disabling work-injuries dropped sharply in 1954, down to 1,860,000-9% b e l o w 1953 a n d t h e lowest total in 15 years. Some of the drop was due to reduced employ ment. In manufacturing, t h e total deaths were 2000, total disabling in juries 390,000.
was the 1954 winner of the Harold Blancke Safety A w a r d in annual intracompany competition. It h a d two lost-time accidents, for a rate of 0.5. Certificates of commendation in the competition were also won at Bridgewater, Va., Bishop, Tex., Hopewell, Va., Linden, N . J., Summit, N. J., fa cilities, a n d at the central trucking divi sion at Cumberland, Md., for establish ing best safety records on a divisional basis. • Ansul Chemical worked over 1 mil lion man-hours in 1954 without a losttime injury, the first time it passed the 1 million mark. In its 39-year history, the company has h a d 29 lost-time ac cidents a n d no deaths. • Cominco recorded 195 lost-time in juries in 1954, 44 fewer t h a n in 1953; this establishes an all-time low of 13 accidents per million man-hours worked. • Ραη-Am S o u t h e r n ' s D e s t r e h a n Re finery worked an accident-free year of 1.2 million man-hours. T h e record was set F e b . 12. • M o n s a n t o ' s C a m d e n , N . J., plant now holds the all-time company safety record of more t h a n 10 consecutive years without a major injury. As part of ceremonies marking the occasion, the plant received a special Executive Committee Plaque, a 10-year Perfect Safety Plaque from Liberty Mutual In-
H a n f o r d Installs Glass Filter For Removal of R a d i o a c t i v i t y Workers at Hanford Atomic Products Operation install a new fibrous glass filter for removal of radioactive particles from exhaust gases. Hanford will use a bed of glass fibers 7 ft. deep and 56 ft. long as a more efficient and less costly alterna tive to sand filters formerly used
• Du Pont h a d the safest year in its history in 1954. I t s frequency rate of 0.33 lost-time injuries per million m a n hours was 407c better than t h e previ ous year's rate of 0.55. Its 90,000 employees worked 177.3 million m a n hours with 57 lost-time injuries. • Celanese
Corp.'s
frequency
rate
was 1.57 lost-time accidents per million man-hours worked in 1954. Com pany's average fire loss was $59, con trasted with t h e national average for general industry of $2529 in 1953. Narrows, Va., fiber manufacturing plant CHEMICAL
AND
ENGINEERING
NEWS
crystalline sfrycture
in stearic acids
how Emersol 120 increased strength of buffing bars and reduced breakage If your product is molded or cast, yoix may be able to profit from this customer experience: Case History 77-47 . . . This uuell-known manufacturer of buffing bars found that the substitution of crystalline Emersol 720 Jor a non-crystalline solid fatty acid increased substantially the strength of his hars, thus reducing breakage both during manufacturing and use. In addition to realising the savings associated with lower breakage, an extra sales appeal of greater safety and economy in use was also gained. Furthermore, he found that the consistent composition and uniformity of Emersol 720 decreased the need for adjusting formulas during processing.
T h e controlled crystalline composition of Emersol 120 Standard will give your products t h e same strength, shrinkage, hardness and texture time after time. These important physical characteristics, coupled with outstanding resistance to rancidity a n d yellowing, heat stability, and oxidation stability will make y o u r products more appealing to customers, easier to sell. So . . . the next time you need solid fatty acids, buy the Emersol b r a n d . . . available only from Emery.
Emery
Fatty Adds & Derivatives Plastolrtn PlastlcEzers Twltchitll Oils, Erwiulslflers
E m e r y i n d u s t r i e s * i n c . , Carew T o w e r , C i n c i n n a t i 2 , Ohio New York; Philadelphia; Lowell, Mas*.; Chicago; San Francisco; Cleveland; Ecclestone Chemical Co., Detroit Warehouse stocks also in SL Louis, Buffalo, Baltimore York
V O L U M E 3 3, N O . 13 ·
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MARCH
2 8, 1 9 5 5
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SAFETY
L/.B I
surance Co., and a Certificate of Com mendation from the National Safety Council.
REPORT
• B. F· Goodrich Chemical's Louisville, Ky., plant receives the President's Cap for the company's most outstanding safety record for the preceding year. T h e plant's 900 people have worked over 2.5 million man-hours since Sept. 3 , 1953 without accident. It also re ceived four other awards from the Louisville Safety Council.
O d o r a n d Color D e v e l o p m e n t in ALKYL ARYLS Problem:
Prevent odor and color reversion during aging of dried alkyl aryls
• Safety banners 10 ft. long by 3 l / 2 ft. wide are available on an annual sub scription basis from National Safety Council. Printed in two colors, they come in two styles, one for indoor dis play, the other for outdoor. A flyer showing miniatures and information on prices may b e obtained from NSC, 425 North Michigan Ave., Chicago 11, 111.
Solution : P r o t e c t i o n a g a i n s t odor and c o l o r degra ChieVed by the S mpo;ndM i o n aso f S a Compound 19 percentagesa dasd i tlow l n Com un
slurry Note
P°
