Diphenylamine manufacture

Diphenylamine is manufactured by the self-condensation of aniline in the presence of a small amount of a mineral acid, such as anhydrous hydrogen chloride, or Lewis acids, such as ferrous chloride or ammonium bromide. 

According to the U.S. International Trade Commission s Synthetic Organic Chemicals, Production and Sales, 1987, the three manufacturers of diphenylamine are Rubicon, Inc., Aristech Chemical Corp., and Uniroyal Chemical Co. No production figures have been given siace 1974, but U.S. production ia the range of 5,000—10,000 t/yr appears reasonable. 

The 5,168-acre Alabama Army Ammunition Plant tract, on the banks of the Coosa River in Talladega County, AL, is 4 miles north of Childersburg, AL (4). Plant operations, between 1942 and 1945, left residues from the manufacture of diphenylamine, TNT, DNT, and tetryl. Some of these compounds have been found on the site, and others are suspected. The shallow water table, draining to the Coosa River, is probably contaminated, but only deeper, uncontaminated aquifers would be used as the source for... 

In the Colour Index both conventional sulphur dyes and their leuco counterparts are allocated the same Cl constitution number a different number is given to the related solubilised version. Thus, for example, Cl Sulphur Black 1 and Cl Leuco Sulphur Black 1 have the reference Cl 53185 whereas Cl Solubilised Sulphur Black 1 appears under Cl 53186. Because of the complexity of the final products, sulphur dyes are classified according to the chemical structure of the organic starting material that predominates in the manufacturing process. Typical intermediates include aromatic amines, with or without nitro and phenolic groups, and diphenylamine derivatives. 

Uses Intermediate in the manufacture of dyes, resins, varnishes, medicinals, perfumes, photographic chemicals, shoe blacks, chemical intermediates, pharmaceuticals solvent vulcanizing rubber isocyanates for urethane foams explosives petroleum refining diphenylamine phenolics fungicides herbicides. 

During World War II N-arylurethanes were extensively used for the manufacture of nitroglycerine powder, e.g. ethylphenylurethane, diphenylurethane, otolylure-thane, also, to a lesser extent, N-arylsubstituted amides of aliphatic acids, e.g. formyl-diphenylamine were used. The latter was used in Japan [33] as gelatinizer and stabilizer. 

The use of certain vanadium compounds as catalysts has been increasing. Vanadium oxy trichloride is a catalyst in making ediylene-propylene rubber. Ammonium metavanadate and vanadium pentoxide aie used as oxidation catalysts, particularly in the production of polyamides, such as nylon, in the manufacture of H>S04 by the contact process, in the production of phdialic and maleic anhydrides, and in numerous other oxidation reactions, such as alcohol to acetaldehyde, anthracene to anthraquinone, sugar to oxalic acid, and diphenylamine to carbazole. Vanadium compounds have been used for many years 111 die ceramics field for enamels and glazes. Colors are produced by various combinations of vanadium oxide and silica, zirconia, zinc, lead, tin, selenium, and cadmium. Vanadium intermediate compounds also are used in the making of aniline Mack used by the dye industry... 

Bulk powders are made in considerable variety, but they consist always of nitrocellulose fibers which are stuck together but are not completely colloided. Some contain little else but nitrocellulose others contain, in addition to potassium and barium nitrates, camphor, vaseline, paraffin, lampblack, starch, dextrine, potassium dichromate or other oxidizing or deterrent salts, and diphenylamine for stabilization, and are colored in a variety of brilliant hues by means of coal-tar dyes. In the United States bulk powders are manufactured by one or the other of two processes, either one of which, however, may be modified considerably the materials are incorporated under wooden wheels, grained, and partially gelatinized, or the grains arc formed in a still where a water suspension of ptdped nitrocellulose is stirred and heated with a second liquid, a solvent for nitrocellulose which is volatile and immiscible with water. 

Desmaroux,13 Marqueyrol and Muraour,14 and Marqueyrol and Loriette15 have studied the diphenylamine derivatives which give a dark color to old powder, and have concluded that they are produced by impurities in the ether which is used in the manufacture or by the oxidizing action of the air during drying and storage. Their presence is not evidence that the powder has decomposed, but indicates that a certain amount of the diphenylamine has been consumed and that correspondingly less of it remains available for use as a stabilizer. 

Diphenylamine in the presence of water thus has an action beyond that which it has when it is added to the nitrocellulose gel (in the absence of a separate water phase) during the manufacture of smokeless powder by the usual process. Being preferentially adsorbed by the nitrocellulose, it drives any acid which may be present out of the nitrocellulose and into the water. After that it fulfils its usual function in the powder. 

Diphenylamine (DPA) is a crystalline compound used chiefly in the manufacture of dyes. 

Uses Diphenylamine is a colorless, monoclinic leaflet substance. It is used in the manufacture of a variety of substances, (e.g., dyestuffs and their intermediates pesticides, antihelmintic drugs, as a reagents in analytical chemistry laboratories). 

Condensation and addition. In both condensation and addition reactions, two or more molecules combine by the elimination of a simple molecule (condensation), or the reaction is stopped after the molecules are joined (addition). There are only a few intermediates manufactured in any considerable quantity by these reactions. An example of a condensation reaction is the formation of the diphenylamine derivative, commonly called nitro delta acid [5]. 

American Method. The process used by the Americans at Edgewood Arsenal for the manufacture of phenarsazine chloride is based on the reaction of diphenylamine with arsenic chloride ... 

Italian Method. During the war. Professor Contardi proposed a method of preparation much more simple than the American process just described. In studying a new process for manufacturing diphenylamine, he observed that the hydrochloride of this base is completely dissociated into hydrochloric acid and diphenylamine when heated to slightly over 100° C. He studied the possibility of using this reaction to prepare phenarsaane chloride by starting from arsenious oxide and diphenylamine hydrochloride, instead of arsenic trichloride and diphenylamine. The equation of this reaction is as follows ... 

In 1976 Arnmann [14] examined nilrocclhilose powder manufactured in 1927 and found derivatives of diphenylamine as follows by TLC 2-nitro, 2,2 -, 2,4-, 4.4 -dinitro-, 2,2, 4-, 2,4,4 -irinitro and tetranitrodiphcnylaminc. Also trace quantities of A -nitroso-4-nitro and A -nitrosn-4,4 dtnitrodiphenyIamine were detected. 

After diazotisation is completed the liquid is allowed to run into an alkaline solution of the phenol or its sulphonic acid, care being taken that the mixture remains alkaline. After some time the dyestuff is salted out, and is generally filtered through a filter-press. The combination of diazo-compounds with amines is somewhat more complicated. Some of these, for instance metaphenylenediamine, combine with diazo-compounds in neutral aqueous solutions while others, like diphenylamine, are dissolved in alcohol, and a concentrated solution of the diazo-compound gradually added. In the manufacture of amidoazobenzene and all compounds in which an intermediate formation of a diazo-amido-compound takes place, a large excess of the amine has to be employed, to hold the diazoamido-compound formed in solution. 

Spandex stretch fiber, based on polyurethanes, was developed by DuPont and appeared in 1962. From this time, polyurethanes would account for the greater part of demand for anilines. Aniline production alone had more than doubled, to over 100 million lbs. per year, between 1939 and 1957, in part to satisfy demand in products other than dyes. Half the US output was consumed in the production of rubber additives, mainly diphenylamine and cyclohexylamine, the latter used as a chain stopper in manufacture of polyurethanes (also as a boiler water additive and, in the US until banned in 1970, in the manufacture of cyclamate sweeteners). Other polymers, such as epoxy resins, relied on the bulk availability of various aromatic amines (Chapter 14). 

Arylation involves the reaction between amines and phenols, aryl halides and aryl amines, including aniline. In arylation, one reactant acts as solvent acidic catalysts and high temperatures are employed. Diphenylamine (A-phenylbenzeneamine, /V-phenylani-line) (8) is made by condensation of aniline in the presence of a small amount of mineral acid catalyst at around 300 °C catalytic reaction of chlorobenzene with aniline at high temperature and pressure and continuous vapor-phase catalytic condensation of aniline. It is a useful intermediate in azo dye manufacture. Crompton is the main US manufacturer of 8, producing 1.3 billion lbs. in 2000. Applications include as lube additives... 

Over half of the remaining market for products used in the processing of rubber is made up of antioxidants, antiozonants and stabilizers, either amino compounds or phenols. Aniline is used to manufacture vulcanization accelerators, antioxidants and antidegradants. Of the latter, several are A-substituted derivatives of p-phenylenediamine and octyl dipheny-lamine. Diphenylamines terminate free-radical reactions by donating the amino hydrogen, and are used to protect a wide range of polymers and elastomers. Many synthetic rubbers incorporate alkylated diphenylamine antioxidants. Other antioxidants include aryl amine resinous products from, e.g. condensation of aniline and acetone in the presence of... 

Nitration of p-nitroaniline (15b), or reacting picric acid with phosphorus pentachloride, yields trinitrochlorobenzene, which on amination affords 2,4,6-trinitroaniline, the explosive picramide. Phosgenation of /V-ethylaniline (26) gives a substituted urea used as a stabilizer for explosives. Diphenylamine (8) is used as a stabilizer, for nitrocellulose explosives as well as for celluloid, and also as a solid rocket propellant. Ethylaniline 26 is employed in the manufacture of centralite, a stabilizer in smokeless powder. Other uses for 15b, the largest volume nitroaniline, include in the production of dyes, antioxidants and pharmaceuticals. 

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