The catalytic combustion of natural gas in a membrane reactor with separate feed of reactants

This paper provides an experimental and modelling analysis of the performan ce of a membrane reactor with separate feed of reactants for the combustion of methane. In this reactor concept methane and air streams are fed at opp osite sides of a Pt/gamma-Al2O3-activated porous membrane which hosts their reaction. The effect of a number of operating parameters (temperature, met hane feed concentration, pressure difference applied over the membrane, typ e and amount of catalyst deposited, time of operation) over the attainable conversion was assessed, while measuring any possible slip of unconverted m ethane to the air-feed side. The maximum specific heat power load which cou ld be attained with the most active membrane in the absence of methane slip was approximately 15 kW m(-2) with virtually no NOx emissions. Such potent ial might perhaps be exceeded if a properly designed membrane is tailored o n purpose. For this sake a model, based on differential heat and mass balan ces throughout the membrane thickness, proved to be a promising design tool , since it allowed proper accordance with the experimental data with a sing le fitting parameter (pre-exponential kinetic constant). (C) 2000 Elsevier Science S.A. All rights reserved.