Maximizing H2 production by combined partial oxidation of CH4 and water gas shift reaction

A dense ceramic membrane reactor has been constructed to exclusively transport oxygen for the partial oxidation of methane (CH4) to syngas (a mixture of CO and H-2) at temperatures of 850-900 degrees C. H-2 production is enhanced in a second catalytic reactor through the water gas shift reaction, in which the CO reacts with steam that is injected into the reactor at a controlled rate to produce CO2 and H-2. Experiments and thermodynamic calculations were used to establish the optimal lower temperature (approximate to 400 degrees C) and lower steam-to-CO ratio (approximate to 2) to achieve thermodynamic efficiency while maximizing H-2 production. No unusual synergisms were observed by the combination of the two processes and the experimental results are in good agreement with thermodynamic predictions. (C) 2000 Elsevier Science B.V. All rights reserved.