PROCESS FOR INCREASING THE ACTIVITY AND FOR EXTENDING THE HIGH-SELECTIVITY DURATION TIME OF SILVER SUPPORT CATALYSTS FOR USE IN THE SYNTHESIS OF ETHYLENE OXIDE

摘要

The activity and the service life of supported silver catalysts used in the preparation of ethylene oxide by the catalytic vapor phase oxidation of ethylene with molecular oxygen are extended by using mixtures of: (a) supported silver catalysts and promoter metal compounds; (b) supported silver catalysts and supported promoter metal compounds; (c) promoter metal compound treated supported silver catalysts and promoter metal compounds; or (d) promoter metal compound treated supported silver catalysts and supported promoter metal compounds. Promoter metal compounds containing about 0.001-0.05% by weight rubidium, about 0.01-0.20% by weight potassium, about 0.001-0.5% by weight cesium or about 0.01-0.25% by weight barium, based on the total weight of catalyst, are suitable.