Catalytic Amination on Y Type Zeolites

Abstract

The vapor phase catalytic aminations of phenol or chlorobenzene, and the activity of catalyst of cation exchanged Y type zeolites were studied. In the amination of phenol, the order of the catalytic activity, at the temperature range from 350° C to 380° C, was HY>CaY>CuY, and the yield of aniline was from 11 mol % to 14 mol %. Effect of the amount of replaced Cu2was also investigated and the maximum yield of aniline was obtained at about 80% exchange degree of Cu²⁺. By the addition of aniline or pyridine to CuY, the yield of aniline was decreased to a constant value. By the addition of hydrogen chloride to NaY or CuY, the yield of aniline was increased. When hydrogen chloride was added too much, the yield of aniline was decreased because of a formation of coke.
In the amination of chlorobenzene, the maximum yield of aniline was 3.0 mol % at 250° C. Above 350° C, benzene was markedly produced. At the same time, it was observed that ammonia was markedly decomposed to hydrogen and nitrogen.
It was suggested that the amination of phenol was mainly promoted by BrOnsted acid sites of zeolites.