Vapor-phase catalytic hydrogenation, aniline manufacture

The predominant process for manufacture of aniline is the catalytic reduction of nitroben2ene [98-95-3] ixh. hydrogen. The reduction is carried out in the vapor phase (50—55) or Hquid phase (56—60). A fixed-bed reactor is commonly used for the vapor-phase process and the reactor is operated under pressure. A number of catalysts have been cited and include copper, copper on siHca, copper oxide, sulfides of nickel, molybdenum, tungsten, and palladium—vanadium on alumina or Htbium—aluminum spinels. Catalysts cited for the Hquid-phase processes include nickel, copper or cobalt supported on a suitable inert carrier, and palladium or platinum or their mixtures supported on carbon. 

Aniline is an aromatic amine used in the manufacture of dyes, dye intermediates, rubber accelerators, and antioxidants. It has also been used as a solvent, in printing inks, and as an intermediate in the manufacture of pharmaceuticals, photographic developers, plastics, isocyanates, hydroquinones, herbicides, fungicides, and ion-exchange resins. It is produced commercially by catalytic vapor phase hydrogenation of nitrobenzene (Benya and Cornish 1994 HSDB 1996). Production of aniline oil was listed at approximately 1 billion pounds in 1993 (U.S. ITC 1994). Chemical and physical properties are listed in Table 1-2. 

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