Carbonized Products of Cumene Catalysed by Nickel Alumina

Abstract

The 14.00% Ni–Al₂O₃ catalyst was prepared by the co-precipitation of mixed hydroxides from their nitrate solutions. The surface area S_BET and X-ray diffraction analysis were carried out. The analysis of nitrogen adsorption data gave a value of 122.8 m²g^–1 for S_BET. The values of d-spacing obtained from the X-ray analysis were examined and the catalyst type was determined at 500ºC. The heterogeneous kinetics of cumene conversion was studied on a Ni–Al₂O₃ catalyst using a flow technique under normal pressure. The catalyst activity was measured in the temperature range 400–480ºC at space valocities ranging from 7.3 to 12.5 x 10^–2 ml min^–1. The gaseous products of the conversion reaction were hydrogen, methane and propene, and the liquid products were cyclohexane, cyclohexene, benzene, toluene and cymelle together with unreacted cumene. The kinetics of the gaseous products and the cyclohexane, cyclohexene, cymene and toluene revealed a zero order reaction, but that of benzene did not. The polymolecular mechanism was proposed.