Catalysis Letters, Vol.103, No.3-4, 239-247, 2005
Study of partial oxidative steam reforming of methanol over Cu-ZnO/samaria-doped ceria catalyst
Partial oxidative steaming reforming of methanol (POSRM) to produce hydrogen selectively for polymer electrolyte membrane fuel cell (PEMFC) powering vehicles was studied over Cu-ZnO/samaria-doped ceria (SDC) catalyst. Compared with Cu-ZnO/alpha-Al2O3 and Cu-ZnO/gamma-Al2O3 catalysts, the Cu-ZnO/SDC catalyst exhibited higher activity for CH3OH conversion and higher selectivity for H-2 production in the POSRM reaction. The higher catalytic performance of Cu-ZnO/SDC appears attributable to the support effect of SDC. Effects of reaction temperature, O-2/CH3OH and H2O/CH3OH molar ratios on the catalytic performance of Cu-ZnO/SDC were investigated. It has been found that the partial-oxidation nature of the POSRM reaction is increased when O-2/CH3OH ratio is increased, and the combustion of methanol and H-2 would occur insignificantly in the POSRM over the Cu-ZnO/SDC catalyst. A higher concentration of steam is beneficial to suppress CO formation over the Cu-ZnO/SDC catalyst. Under the experimental conditions of the present work, the O-2/CH3OH and H2O/CH3OH molar ratios should be about 0.02 and 1.0-2.0, respectively, in order for Cu-ZnO/SDC to achieve an optimum catalytic performance.