US Patent 7928034 Process for producing olefin oxide

There is disclosed a process for producing an olefin oxide characterized by contacting an olefin and oxygen, in the presence of water and a halogen compound, with a silver catalyst, wherein the silver catalyst is a silver catalyst that is obtainable by contacting metal silver, a silver compound or a mixture of both with an alkaline earth metal carbonate and that has an alkali metal content of 1,500 ppm or less based on the total weight of the silver catalyst.