Simultaneous isobutane dehydrogenation and hydrogen production in a hydrogen-permselective membrane fixed bed reactor

Abstract

In this study, performance of hydrogen-permselective membrane fixed bed reactors to produce isobutene is studied at steady state condition. The proposed reactors have been modeled heterogeneously based on the mass and energy conservation laws. The considered reaction networks in the model are isobutene dehydrogenation as the main reaction, and hydrogenolysis, propane dehydrogenation as well as coke formation as side reactions that all occur on the catalyst surface. The coke deposition on the catalyst surface results an activity profile along reactors. The reactions occur in the tube side and the hydrogen permeates from the reaction zone to the sweep gas stream. Decreasing the hydrogen concentration over the catalyst pellets improves isobutane conversion and isobutene selectivity. To prove the performance of the proposed configuration, simulation results for membrane process are compared with the conventional process at the same operating condition. In this configuration, the isobutene production rate is enhanced about 10.81% compared to the conventional process at the same catalyst loading.