On the applicability of membrane technology to the catalysed dry reforming of methane

The coupling of a catalytic reactor and a separator in the same unit is an attractive concept which still entails complex technological problems caused by the generally severe conditions at which a large part of heterogeneous catalytic reactions take place. The application of this technology to the conversion enhancement in reversible chemical reactions with high reaction enthalpies can provide interesting advances in the methane conversion processes. This paper analyses the applicability of mesoporous ceramic filters in a membrane reactor to carry out the reforming of methane with carbon dioxide. The effect of the variation of the sweep gas flow rate as compared to the feed rate of reactants has been studied. It has been observed that, even for membranes in which the main mechanism for the gas transport is the Knudsen diffusion, high sweep gas flows rates induce large changes in the distribution of species at both sides of the membrane. This change is dependent on the membrane permeance and gives place not only to a moderate conversion enhancement but also to maximise selectivity to hydrogen by hindering the progress of the secondary reverse water gas shift reaction. (C) 2002 Elsevier Science B.V. All rights reserved.