Highly selective propene epoxidation with hydrogen/oxygen mixtures over titania-supported silver catalysts

Silver supported on titania was found to be active for propene epoxidation using hydrogen/oxygen mixtures at 50 °C. The dependence of the activity on the preparative method is pronounced, i.e., only catalysts prepared by using deposition–precipitation exhibit activity. Optimum performance was found for 2 wt% Ag/TiO2 calcined at 400 °C. The propene epoxidation activity, the activity in the low-temperature CO oxidation, in propane oxidation and deactivation behavior of these silver catalysts strongly resemble the results obtained for the Au/TiO2 catalysts developed by Haruta.