Effect of ZrO2 on steam reforming of methanol over CuO/ZnO/ZrO2/Al2O3 catalysts

The CuO/ZnO/ZrO2/Al2O3 catalysts were prepared by co-precipitation method and the effects of ZrO2 on steam reforming of methanol over CuO/ZnO/Al2O3 catalysts with various CuO/ZnO ratios (40/50–10/80) were examined and discussed. Zirconium oxide improved the dispersion and reducibility of the CuO/ZnO/Al2O3 catalysts and promoted the adsorption of methanol. The promoting effect of ZrO2 was observed only on the CuO/ZnO/Al2O3 with the CuO/ZnO ratio less than 0.8. A lower CuO/ZnO ratio in the CuO/ZnO/Al2O3 catalysts was associated with greater promoting effect of ZrO2 in the SRM reactions, which depend on appropriate interactions through the interface between CuO and ZnO.

► ZrO2 improved the dispersion and reducibility of the CuO/ZnO/Al2O3 catalysts.
► ZrO2 also enhanced the adsorption of methanol on the CuO/ZnO/Al2O3 catalysts.
► A lower CuO/ZnO ratio was associated with more promoting effect of ZrO2.
► An appropriate CuO/ZnO ratio 0.75–0.8 was needed for the promoting effect of ZrO2.