H2 from steam reforming of ethanol at low temperature over Ni/Y2O3, Ni/La2O3 and Ni/Al2O3 catalysts for fuel-cell application

The catalytic activities of three nano-sized nickel catalysts Ni/Y2O3, Ni/La2O3 and Ni/Al2O3, using nickel oxalate as precursor and by impregnation-decomposition-reduced method, have been investigated for the reactions of steam reforming of ethanol at low temperature. Properties of structure and surface of catalysts were tested by XRD, XPS, XES, SEM and BET area. The initial reaction kinetics of ethanol over the catalysts was studied by steady-state reaction and a first-order reaction with respect to ethanol was found. It is found that the catalysts Ni/Y2O3 and Ni/La2O3 exhibit relative high activity for ethanol steam reforming at 250 degreesC with a conversion of ethanol of 81.9% and 80.7%, and a selectivity of hydrogen of 43.1% and 49.5%, respectively. When temperature reached 320 degreesC, the conversion of ethanol increased to 93.1% and 99.5% and the selectivity of hydrogen was 53.2% and 48.5%, respectively. The catalyst Ni/Al2O3 exhibits relative lower activity for ethanol steam reforming and hydrogen selectivity. However, the three catalysts all have long-term stability for ethanol steam reforming. (C) 2005 International Association for Hydrogen Energy. Published by Elsevier Ltd. All rights reserved.