Activity of Aniline Methylation over Fe-Cu-Cr Ternary Spinel Systems

A series of spinels having the general formula CuCr2-xFexO4 with x = 0.25, 0.75, 1.25, 1.75 were pre-pared by co-precipitation method. The catalysts were characterized by various physico-chemical meth-ods like XRD, BET, SEM, EDX and TPD. The reaction of aniline with methanol was studied in a fixed-bed reactor system as a potential source for the production of various methyl anilines. It was observed that systems possessing low ‘x ’ values are highly selective and active for N-monoalkylation of aniline leading to N-methylaniline. Reaction parameters were properly varied to optimize the reaction condi-tions for obtaining N-methylaniline selectively and in better yield. Among the systems CuCr1.75Fe0.25O4 is remarkable due to its very high activity and excellent stability. Under the optimized conditions N-methylaniline selectivity exceeded 91%. CuCr1.25Fe0.75O4 gives better conversion than CuCr1.75Fe0.25O4 in CuCr2-xFexO4 series. The Lewis acid sites of the catalysts are mainly responsible for the good cataly-