Methylcyclohexane dehydrogenation for hydrogen production via a bimodal catalytic membrane reactor

The dehydrogenation of methylcyclohexane (MCH) to toluene (TOL) for hydrogen production was theoretically and experimentally investigated in a bimodal catalytic membrane reactor (CMR), that combined Pt/Al2O3 catalysts with a hydrogen-selective organosilica membrane prepared via sol-gel processing using bis(triethoxysilyl) ethane (BTESE). Effects of operating conditions on the membrane reactor performance were systematically investigated, and the experimental results were in good agreement with those calculated by a simulation model with a fitted catalyst loading. With H-2 extraction from the reaction stream to the permeate stream, MCH conversion at 250 degrees C was significantly increased beyond the equilibrium conversion of 0.44-0.86. Because of the high H-2 selectivity and permeance of BTESE-derived membranes, a H-2 flow with purity higher than 99.8% was obtained in the permeate stream, and the H-2 recovery ratio reached 0.99 in a pressurized reactor. A system that combined the CMR with a fixed-bed prereactor was proposed for MCH dehydrogenation. (c) 2015 American Institute of Chemical Engineers AIChE J, 61: 1628-1638, 2015