Direct epoxidation of propene using gold dispersed on TS-1 and other titanium-containing supports

Highly dispersed gold catalysts on a titanium-containing support are promis ing catalysts for the low-temperature direct epoxidation of propene. Gold d ispersed on TS-1 and other titanium-based support materials has been used t o selectively (>99%) epoxidize propene using a hydrogen-oxygen mixture. The propene conversion, however, remains low (<2%). The mode of operation of t hese catalysts, which is based on the close cooperation between the gold an d the support material, is discussed and some mechanistic models are postul ated. An investigation has been made into the cause of the relatively low c atalyst activity, the efficiency of the catalyst toward the use of hydrogen , and the deactivation of the catalyst. The most important cause for the lo w propene oxide yields is explained by a strong adsorption of propene oxide on the catalyst.