| 摘要 |
The present solution relates to a method of preparation of 4-aminodiphenylamine through an intermediate preparation of 4-nitrodiphenylamine and/or 4-nitrosodi-phenylamine and/or their salts by th e reaction of aniline with nitrobenzene in a liquid medium at a temperature of 50 to 130 .degree.C, under atmospheric or reduced pressure, in an inert atmosphere or in the presence of air oxygen, with subsequent hydrogenation of an intermediate of 4-nitrodiphenylamine and/or 4-nitrosodiphenylamine and side products, and by isolation of 4-aminodi-phenylamine and the side products and recycling of unconverted materials. The reaction of aniline with nitrobenzene, is perform ed in a reaction system, consisting of a solution of salts of zwitterions with hydroxides of a general formula HO-/(R1R2R3)N+-CHR4-(CH2)x-Y-/Z+ where R1 and R2 means methyl to dodecyl, R3 means methyl, ethyl, phenyl, benzyl, R4 means hydrogen or methyl x means an integer of 0 to 5, Y- means CO2-, SO3- and Z+ means a cation of an alkali metal Na, K, Cs or a tetrasubstituted quaternary ammonium cation, like tetramethylammonium, or their mutual combinations, wherein the amounts of both the zwitterion salt and hydroxide are at least equimolar amounts related to the amount of nitrobenzene in the reaction system, wherein 4-nitrosophenylamine and/or 4-nitrodiphenylamine arise, which after hydrogenation produces 4-ADFA, and after the reaction at least a half of the reaction medium is recycled. The reaction medium is form ed separately and/or it will be formed in situ in the reaction system from starting materials. The liquid medium for the reaction of aniline with nitrobenzene i s formed of water and/or at least one organic compound, chosen from among aniline, pyridine, toluene, xylene, cyclohexane and aliphatic alcohols with 1 to 4 of carbon atoms in the molecule.
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