Secondary chemistry in the selective oxidation of ethylene: Effect of Cl and Cs promoters on the adsorption, isomerisation, and combustion of ethylene oxide on Ag(111)

Abstract The adsorption/desorption, isomerisation, and combustion of ethylene oxide on single crystal Ag(111) have been studied under conditions which are pertinent to ethylene epoxidation. The effects of chlorine on the uptake and isomerisation of ethylene oxide are examined, as is the effect of Cs on the burning reaction. These data complement our earlier results and suggest that the observed promoter effects are largely electronic in origin. CO 2 strongly inhibits the combustion reaction, apparently by converting chemisorbed oxygen to a carbonate species.