Patent ID: 7507845

Claim:
A process for the epoxidation of an olefin to an olefin oxide comprising: contacting a feed including at least oxygen and an olefin in a reactor with a catalyst that includes a support having a bimodal pore size distribution, with a first mode of pores having a mean diameter ranging from about 0.01 μm to about 5 μm and a second mode of pores having a mean diameter ranging from about 5 μm to about 30 μm, a catalytically effective amount of silver or a silver-containing compound, a promoting amount of rhenium or a rhenium-containing compound, and a promoting amount of one or more alkali metals or alkali-metal-containing compounds, said reactor including at least a reactor outlet and said olefin oxide produced by said contacting has a concentration in the reactor outlet that is greater than about 2.2% by volume.