(135b) Direct Epoxidation of Propene Over Gold Catalysts: Kinetics of Epoxidation and Water Formation

The direct epoxidation of propene over gold catalysts is an attractive environment friendly alternative for the two current processes. The chlorohydrin process produces large amounts of salt waste and chlorinated side products. The hydroperoxide processes are complex, energy intensive, and produce a co-product in a 2-3 times larger quantity.

The gold-titania based catalysts directly produce propene oxide in a single reactor, at mild conditions, high selectivities with only water as a co-product. A hydrogen/oxygen mixture is used as oxidant, producing a peroxide intermediate on the gold particles as the true oxidant. Before these catalysts can be used industrially, however, they still need improvements with respect to activity, stability, and hydrogen efficiency. This study will present a kinetic study into both the epoxidation and the water formation. The kinetic information is used to design better catalysts and propose alternative reactor concepts for this system.