EFFECT OF MICROWAVE IRRADIATION ON THE CATALYTIC PROPERTIES OF SILVERIN ETHYLENE EPOXIDATION

The effect of microwave irradiation on an Ag/alpha-Al2O3 catalyst for ethylene epoxidation with silver particle sizes of 100-10 000 Angstrom and the average size 2000 Angstrom was examined. It was found that, o n the catalyst preliminary reduced with hydrogen, the reaction rates t oward both epoxidation and carbon dioxide formation considerably incre ased under exposure to a microwave field. This effect gradually decrea sed or even disappeared as the catalyst attained a steady state. A qua ntitative estimation of microwave absorption by the catalyst demonstra ted that the effects associated with heating can be neglected. It was suggested that the reason for the observed phenomenon can be the modif ication of the catalyst electronic properties under exposure to microw ave irradiation.