THE SILVER CATALYZED OXIDATION OF ETHYLENE: III. KINETICS OF ETHYLENE OXIDE OXIDATION

Abstract

A flow type apparatus was used for kinetic studies of the silver catalyzed oxidation of ethylene oxide (EtO) by oxygen at 274 °C. Using N2 as diluent the concentrations of O2 and ethylene oxide were varied independently from 9.9 to 79% and 2.35 to 9.4% respectively while a total pressure of 1 atmosphere was maintained. Flow rates were varied to give a range of contact times varying from 0.06 to 0.25 sec. It was shown that EtO is oxidized without previous dissociation into C2H4 and O2. The dependence of the initial rate of oxidation of EtO on reactant concentrations excludes isomerization of EtO (to acetalde hyde) as a main step in its oxidation, and a direct oxidation mechanism is suggested. The results of a few experiments to determine the extent of isomerization of EtO to acetaldehyde in the absence of oxygen are presented. No steady state could be achieved but the results may be used semiquantitatively to support the belief that isomerization is not the rate determining step in the oxidation of ethylene oxide.