Catalyst for oxidation of ethylene to ethylene oxide and process for preparing the catalyst

摘要

A supported silver catalyst selective to the formation of ethylene oxide in the reaction of ethylene with molecular oxygen is made by depositing an amount of an alkali metal sufficient to depress the activity and selectivity of the silver catalyst below that of its alkali-free state and thereafter heating the alkali metal-containing catalyst in a substantially oxygen-free atmosphere to reactivate it. In one embodiment, a large amount of alkali metal is deposited which removes substantially all activity from the silver catalyst and then activity and selectivity for oxidation of ethylene to ethylene oxide is recovered and enhanced by heating the catalyst in a nitrogen atmosphere to a temperature above 400 DEG C. for a sufficient period of time.