PRODUCTION
SAFETY Phenyldiazosulfide Revealed As A Dangerous Explosive Phenyldiazosulfide is so unstable that it cannot b e kept at room temperature for more than a few minutes without decom position, according to W . R. Tomlinson, Jr., of National Fireworks Ordnance Corp. U p o n drying, the compound explodes spontaneously. When h e w a s with Picatinny Arsenal (until recently) Dr. Tomlin son investigated a suggestion by Burnard T. Pull of Cumberland, Md., that phenyl diazosulfide, which can easily and con veniently b e prepared from cheap raw materials, might offer possibilities as a military explosive. T h i s type of chemical compound, in general, is thermodynamically unstable and relatively sensitive and h e n c e m i g h t possibly b e suitable for use as an initiator or friction sensitive primercomponent. Picatinny Arsenal, therefore, prepared a sample of phenyldiazosulfide and the p-nitrophenyl derivative to determine their explosive characteristics. T h e diazonium sulfides were prepared by diazotizing aniline, or nitraniline, neutraliz i n g , and passing hydrogen sulfide through t h e diazochloride solution, or adding so dium sulfide to it. The following equa tions indicate the reactions involved in t h e preparation o f phenyldiazosulfide:
NH2
NaNQ 2 HX
N=N-X M .
Cr
•N—N—S—N=N—(
T h e reactions were carried out with ice cooling. T h e y can be prepared in either aqueous or nonaqueous media, but due to their unusual sensitivity, they should be handled in solution or in slurry form with a large excess of solvent. N o more than 0 . 5 to 1.0 gram of product was prepared at one time and only minute quantities were dried. The samples of phenyldiazosulfide and p-nitrophenyldiazosulfide displayed t h e extreme instability and sensitivity characteristics of diazonium salts in gen eral. T h e phenyl compound is a red solid of extreme sensitivity and low stability, which explodes violently w h e n air dried at room temperature. The w e t solid de composes slowly at room temperature and explodes w h e n heated or struck. Even the more stable nitro compound is so sensitive and unstable that it is exceedingly dan gerous. It was obtained as a fine yellow crystalline powder, which is difficult to explode w h e n wet and is easily dried with o u t change at room temperature. The p-nitrophenyldiazosulfide w a s found to b e exceedingly sensitive w h e n dry and can
VOLUME
29,
NO.
52
FORUM F o r further i n f o r m a t i o n on a n y keyed item m e n t i o n e d h e r e , see coupon on p a g e 5 4 7 5
be detonated even by rubbing it on smooth linoleum with a soft object. In the explosion temperature tests con ducted, μ-nitrophenyldiazosulfide det onated in 5 seconds at 82° C , while at 75° C. it exploded in about three minutes. This 5-second explosion temperature is far lower than tor t h e most sensitive mili tary explosives n o w in use. For example, the 5-second explosion temperature for lead azide was 335° C ; for tetryl, 260° C ; and for mercury fulminate, 208° C. In the impact sensitivity test, using the Bureau of Mimes apparatus, the sulfide was detonated hy a 5-centimeter fall of the 500-gram weight, while a fall of 65 centimeters was required to explode com mercial lead azide. These tests show the significant difference between the diazosulfides and usable and relatively safe explosives and emphasize t h e care with which they must be handled.
Telescoping Tilting Foam Tower A portable device for discharging firesmothering foam into a burning oil tank has been developed by Pyrene Manufac turing Co. This equipment, called a Py rene Foam Tower, claims t h e advantages of mobility over rough terrain, ease and speed of erection b y three or four men, and efficient delivery o f large volumes of foam onto tanks u p to 50 feet in height. T h e equipment is assembled in two sec tions: a base with u n i q u e screw-tilting gear mechanism and four spikes for use in case of rough ground; and a telescoped 20-foot, three-section tower with manual winch, two swivel-jointed push poles, and stainless steel guy ropes. A β-inch foam column ends i n a heat-resistant stainless steel dis charge head. T h e tower is light a n d compact. Made principally of aluminum it weighs only 4 7 5 pounds complete a n d is easily carried manually or on a small truck. It m a y b e quickly and easily assembled, erected, and delivering foam in a f e w minutes. A builtin or a forcing-type foam maker with water capacity of 3 0 0 gallons per minute makes 2000 to 3000 gallons per minute of Pyrene air foam. The tilting mechanism simplifies the application of foam for, with the base i n a stationary position, the dis charge head can b e moved forward 3 t o 5 feet over the tank edge to discharge foam against the inner side of the tank. S 1
tions of irritating dust. The hood may b e used either with or without a respirator, by means of easily interchangeable frames and windows. T h e hood itself is o f light weight cotton duck, and a close b u t com fortable fit is obtained by adjustable neck and under-arm w e b straps. Large win dows made of nonflammable acetate sheet ing provide ample vision for extra safety. They can be replaced without removing the frame. With the respirator window and frame assembly, the hood will accom modate respirators which provide protec tion against dusts and low concentrations of common industrial gases and vapors. S 2
Dry Chemical Fire Extinguisher A dry chemical fire extinguisher, d e signed for installation o n Diesel and turbo electric locomotives has been developed by Ansul Chemical Co. T h e unit is capable of storing and expelling 150 pounds of dry chemical, the principal ingredient of which is specially treated sodium bicar bonate. Dry chemical has been found to be most effective in extinguishing fires of flammable liquids and electrical equip ment. The equipment consists of a welded steel container and is pressurized for u s e by opening a nitrogen cylinder valve. T h e nitrogen passes through a pressure regu lator into the dry chemical tank. T h e dry chemical is supplied under pressure through the outlet valve and piping to t h e hose. S 3
MORE RESORCINOL for Defense !
• Through expanding production facili ties, our Chemical Division plans t o manu facture more Resorcinol. Distribution of Koppers Resorcinol is now governed by Schedule 6 under N P A Order M-45. Many end products, resulting from t h e reactions of Resorcinol, are essential t o the defense effort. Typical products: ex plosives, medicinals, woodworking adhesives, dyestuffs—plus c o m p o u n d s t h a t make rubber adhere better to fabrics and cords. Koppers Resorcinol (meta-dihydroxybenzene) is a water-soluble, crystalline, dihydric phenol. Highly reactive, this com pound undergoes typical phenolic reac tions such as nitration, alkylation, alde h y d e condensation, etherification a n d oxidation. Bulletin C-9-124 gives a detailed de scription of the properties, uses and chem ical reactions of Resorcinol. Copies are available on request.
Lightweight Dust Hood A lightweight dust h o o d has been an nounced b y Willson Products, Inc. The hood will be useful to anyone working i n atmospheres containing heavy concentra
» DECEMBER
24,
1951
KOPPERS C O M P A N Y , I N C . Chemical Division, Depl. CEN-12-24 Kopp«r· Blag., Pittsburgh 19, Pa.
5473
