Methanol steam reforming; Effects of various metal oxides on the properties of a Cu-based catalyst

Abstract

Ternary Cu/ZnO/metal oxide catalysts are prepared through the co-precipitation method under strict control of parameters like pH, calcination conditions, and precipitation temperature in a systematic manner. The metal oxides applied in this study consist of Al₂O₃, ZrO₂, La₂O₃ and Ce₂O₃. The distinction of this work in comparison with similar research is a comprehensive investigatation of the catalytic properties of metal oxides (including conversion, selectivity and stability) which have the potential for use in the methanol steam reforming process. The catalysts are characterized through XRD, SEM and BET. The prepared catalysts are applied in methanol steam reforming in a fixed bed reactor. A TGA analysis performed for all four catalysts determined that the Ce₂O₃ and ZrO₂ metal oxide catalysts showed the best results in terms of stability with a coke formation of 0.7wt% and 0.8wt%, respectively; and maximum surface area is related to Cu/ZnO/Ce₂O₃, which can result in excellent stability and Cu dispersion. Overall, the obtained results indicate that the ZrO₂ metal oxide catalyst is the best candidate to be applied in methanol steam reforming due to its higher activity, selectivity and yield. The hydrogen selectivity and yield of Cu/ZnO/ZrO₂ after 6 hours of experiment were 80.02% and 46.4%, respectively.