Catalyst for oxidising ethylene to its oxide

Catalyst for the oxidation of ethylene to ethylene oxide contg. Ag, AgCl and Cd cps. on a support based on corundum, is improved by also contg. Cs and Ca cpds. and has the following compsns., by wt. 10-25 Ag, 0.02-0.05 AgCl, 0.3-1.1 Cd cpd., 0.04-0.08 Cs cpd., 0-1.2 Ca cpd. and balance corundum. The catalyst gives a selectivity of 76-82% and a productivity of 200-1000g ethylene oxide/l catalyst. Ethylene oxide is used for the prodn. of mono- and polyethylene-glycols, surfactants, synthetic biodegradable detergents, ethanolamine, ethyleneglycoether etc. A soln. of AgNO3, Cd(NO3)2 and Ca(NO3)2 is added to a boiling Na2CO3 soln. The residue of carbonates obtd. is washed to remove the NO3- and Na+ ions and is then mixed with an aq. ethyleneglycol soln. contg. a Cs cpd. The obtd. suspension is vigorously stirred, then heated and finally introduced into the pores of a corundum support. The support pref. has a grain size of 0.1-7 mm, a specific surface of 0.1-0.5 sq.m/g and a porosity of 30-45%.