Feasibility Study of Employing a Catalytic Membrane Reactor for a Pressurized CO2 and Purified H2 Production in a Water Gas Shift Reaction

Abstract

The effect of two important parameters of a catalytic membrane reactor (CMR), hydrogen selectivity and hydrogenpermeance, coupled with an Ar sweep flow and an operating pressure on the performance of a water gas shift reaction in a CMRhas been extensively studied using a one-dimensional reactor model and reaction kinetics. As an alternative pre-combustion CO2capture method, the feasibility of capturing a pressurized and concentrated CO2 in a retentate (a shell side of a CMR) andseparating a purified H2 in a permeate (a tube side of a CMR) simultaneously in a CMR was examined and a guideline for ahydrogen permeance, a hydrogen selectivity, an Ar sweep flow rate, and an operating pressure to achieve a simultaneous captureof a concentrate CO2 in a retentate and production of a purified H2 in a permeate is presented. For example, with an operatingpressure of 8 atm and Ar sweep gas for rate of 6.7 × 10-4 mols-1, a concentrated CO2 in a retentate (~90%) and a purified H2 in apermeate (~100%) was simultaneously obtained in a CMR fitted with a membrane with hydrogen permeance of 1 × 10-8 molm-2s-1Pa-1 and a hydrogen selectivity of 10000.