Journal of Catalysis, Vol.274, No.2, 251-258, 2010
Development of a new electrochemical catalyst with an electrochemically assisted regeneration ability for H-2 production at low temperatures
A new electrochemical catalyst (Pt-Pt/VSZ/Na-beta Al2O3) has been prepared and characterized for the H-2 production at low temperature from CH4 with a high CO2 selectivity. It has been tested under electrochemical promotion conditions under different reaction systems: steam reforming, partial oxidation and autothermal steam reforming. Among them, the latter system seems to be the most suitable one for the operation of the electrochemical catalyst in a cyclical way between positive and negative polarizations. Under positive polarization, the electrochemical catalyst produced a high amount of H-2. However, it was deactivated due to a strong increase in the CH4-derived chemisorption species, which led to carbon deposition. Nevertheless, the subsequent application of negative polarization led to a strong increase in the coverage of O-2- and H2O-derived species that caused the removal of the deposited carbon and, hence, the regeneration of the catalyst. The possibility of in situ electrochemical regeneration of a catalyst under fixed conditions could have a significant importance from both theoretical and technological points of view. (C) 2010 Elsevier Inc. All rights reserved.
Keywords:Electrochemical promotion;NEMCA effect;H-2 production;Methane steam reforming;Partial oxidation;Autothermal steam reforming;Electrochemical regeneration