A new method of low-temperature methanol synthesis on Cu/ZnO/Al_2O_3 catalysts from CO/CO_2/H_2

摘要

A new synthesis method of low-temperature methanol proceeded on Cu/ZnO/Al_2O_3, catalysts from CO/CO_2/H_3 using 2-butanol as promoters. The Cu/ZnO/Al_2O_3 catalysts were prepared by co-impregnation of r-Al_2O_3 with an aqueous solution of copper nitrate and zinc nitrate. The total carbon turnover frequency (TOF), the yield and selectivity of methanol were the highest by using the Cu/ZnO/ Al_2O_3 catalyst with copper loading of 5% and the Zn/Cu molar ratio of 1/1, which precursor were not calcined, and reduced at 493 K. The activity of the catalysts increased due to the presence of the CuO/ZnO phase in the oxidized form of impregnation Cu/ ZnO/Al_2O_3 catalysts. The active sites of the Cu/ZnO/Al_2O_3 catalyst for methanol synthesis are not only metallic Cu but also special sites such as the Cu-Zn site, i.e. metallic Cu and the Cu-Zn site work cooperatively to catalyze the methanol synthesis reaction.