Kinetics and mechanism of ethylene hydroformylation over Rh-Y zeolite under atmospheric pressure

Abstract

Ethylene hydroformylation over Rh-Y zeolite has been studied kinetically. The rate of formation of propionaldehyde is approximately proportional to the partial pressure of ethylene and decreases as the partial pressure of carbon monoxide increases. The rate is proportional to the square root of the partial pressure of hydrogen. In the case of ethylene hydroformylation with deuterium almost no appreciable isotope effect on the rate was observed. On the basis of these results a reaction mechanism is proposed via the formation of a propionyl intermediate by the reaction between an ethyl intermediate and adsorbed carbon monoxide. The propionyl-intermediate-formation step is proposed to be rate determining for ethylene hydroformylation over the Rh-Y zeolite.