The composition (CuO/ZnO/Al(2)O(3) = 30/60/10) of a commercial catalyst G66B was used as a reference for designing CuO/ZnO/CeO(2)/ZrO(2)/Al(2)O(3) catalysts for the oxidative (or combined) steam reforming of methanol (OSRM). The effects of Al(2)O(3), CeO(2) and ZrO(2) on the OSRM reaction were clearly identified. CeO(2), ZrO(2) and Al(2)O(3) all promoted the dispersions of CuO and ZnO in CuO/ZnO/CeO(2)/ZrO(2)/Al(2)O(3) catalysts. Aluminum oxide lowered the reducibility of the catalyst, and weakened the OSRM reaction. Cerium oxide increased the reducibility of the catalyst, but weakened the reaction. Zirconium oxide improved the reducibility of the catalyst, and promoted the reaction. A lower CuO/ZnO ratio of the catalyst was associated with greater promotion of ZrO(2). The critical CuO/ZnO ratio for the promotion of ZrO(2) was approximately 0.75-0.8. Introducing of ZrO(2) into CuO/ZnO/Al(2)O(3) also improved the stability of the catalyst. Although Al(2)O(3) inhibited the OSRM reaction, a certain amount of it was required to ensure the stability and the mechanical strength of the catalysts. (C) 2010 Professor T. Nejat Veziroglu. Published by Elsevier Ltd. All rights reserved.
