Effect of ultra-fine gold particle addition to metal oxides in ethylene oxidation

摘要

Oxidation of ethylene was carried out over alumina-supported metal oxide catalysts and highly dispersed gold catalysts respectively, under atmospheric pressure. The ethylene was completely oxidized to produce carbon dioxide and water with both metal oxide and gold catalysts. The activity of gold catalyst prepared by deposition method was much higher than that of supported metal oxide catalysts. Ultra-fine gold particles on Co_3O_4 were more active than on Al_2O_3. Fe_2O_3/Al_2O_3 and MnO_2/Al_2O_3 catalysts were more active than MoO_3/Al_2O_3 catalyst. The activity of the supported metal oxide catalysts was greatly enhanced by addition of gold particles. It was therefore considered that gold particles promote dissociate adsorption of oxygen and the adsorbed oxygen reacts with adsorbed ethylene on support adjacent to the active site.