Catalysts for the production of ethylene oxide

A catalyst for the production of ethylene oxide by the oxidation of ethylene with oxygen which consists essentially of silver supported on a porous heat resisting support, a group VI A transition metal selected from the group consisting of chromium, molybdenum and tungsten, an alkali metal selected from potassium, rubidium and cesium, and sulphur, said catalyst including 3 to 50% by weight of silver and 0.1 to 5 gram atoms of the transition metal, 0.1 to 10 gram atoms of sulphur and 0.1 to 15 gram atoms of the alkali metal per million grams of catalyst.