Verfahren zur Steigerung der Aktivitaet und zur Verlaengerung der Standzeit bei hoher Selektivitaet von Silber- Traeger-Katalysatoren fuer den Einsatz zur Ethylenoxid-Syn these

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.