Catalytic membrane reactor--modeling and experiments of a microporous membrane separation-reaction system

This research demonstrated the feasibility of combining the technologies of membrane separations, heterogeneous catalysis, and reaction engineering in a single unit operation. The catalytic membrane reactor applied to the gas-phase reaction of cyclohexane dehydrogenation is investigated, using a platinum-impregnated Vycor glass membrane. Both the equilibrium shift by selective separation and the pressure-variation effect contributed to the higher total conversion than the original equilibrium conversion of the reaction which was based on the feed-side conditions. Numerical simulations using a single-cell model showed good agreement with experimental results. Theoretically, the performance of the catalytic membrane reactor was compared with that of an inert-membrane reactor packed with catalysts on the feed side, a pressure gradient plug flow reactor, a constant pressure plug flow reactor, and a mixed flow reactor. The catalytic membrane reactor is better than the inert-membrane reactor with catalysts on the feed side in terms of total conversion, for the reaction system that has an increase of total number of moles upon reaction, for the operation at high space time. However, the total conversion of the catalytic membrane reactor may not be better than that of a plug flow reactor or mixed flow reactor operated at lower pressure for the model reaction.