Intrinsic Kinetics of Dehydrogenation of Isobutane over K2O-CuO-Cr2O3/Al2O3 Catalyst

Abstract

The intrinsic kinetics and mechanism of direct dehydrogenation of isobutane were studied over K-Cu-Cr/Al2O3 catalyst. The experiments had been carried out in a fixed-bed reactor with eliminating the influence of both internal and external diffusion at 470-510 o C and space velocity of 2500-4000 h -1 under atmospheric pressure. Based on the Langmuir-Hinshelwood mechanism, the intrinsic kinetics models were established, and they were verified by statistical analysis. The parameters in the models were estimated by using the method of Simplex-Metho d (SM) combined with General Global Optimization Algorithm. The results of the kinetics modeling showed that the rate-determining step was the surface reaction process, which was the best one to describe the experimental data. The activation energy of dehydrogenati on reaction was obtained. And the models can provide an important basis for the design of industrial reactor.