Influence of preparation method on performance of Cu/Zn-based catalysts for low-temperature steam reforming and oxidative steam reforming of methanol for H₂ production for fuel cells

Several methods (impregnation, co-precipitation and hydrothermal synthesis) have been comparatively examined for the preparation of precursors to Cu/Zn/Al catalysts. Steam reforming and oxidative steam reforming of methanol was performed using the laboratory-prepared and a commercial Cu/Zn/Al catalysts at a relatively low temperature (230°C) for catalytic production of H₂. The results show that the preparation method significantly affects the catalyst performance with respect to methanol conversion, H₂ yield and CO concentration. The catalyst with lower copper-reduction temperature shows higher activity for methanol conversion at lower temperature. The best Cu/Zn/Al catalyst has been prepared by a co-precipitation method, which shows high activity for methanol conversion (99-100%) and H₂ production (71-76%) with very low CO concentration (0.05-0.15%) in steam reforming (H₂O/methanol = 1.43 mol ratio) and in oxidative steam reforming (O₂/methanol = 0.158-0.474 mol ratio) at a low temperature (230°C).