Continuous process for the synthesis of unsymmetrical, substituted diphenylamines.

摘要

A continuous process for the synthesis of unsymmetrical, substituted diarylamines in which a mixture of a soluble catalyst dissolved in a substituted phenol and a primary arylamine are reacted at an elevated temperature and pressure in a reactor to form a reaction mixture comprising a substituted, unsymmetrical diamine, a diphenylamine, catalyst, unreacted primary arylamine, unreacted substituted phenol, water and ammonia, which is flash separated in a flash separator to a vapor phase containing the unreacted primary arylamine, unreacted substituted phenol, water and ammonia components while substituted, unsymmetrical diamine and diphenylamine components are maintained in a liquid phase. The vapor phase is removed from the flash separator, subjected to reduced pressure, cooled and fed into a second flash separator where the water and ammonia components are flash separated to vapor phase while the unreacted primary arylamine and unreacted substituted phenol are maintained in the liquid phase. The unreacted primary arylamine and unreacted substituted phenol are then removed from the second flash evaporator and recycled in the continuous process.