Carbon Deposition Effects in Co Hydrogenation over Alumina- and Y Zeolite-Supported Cobalt Catalysts

Abstract

While carbon deposition causes greater deactivation of smaller cobalt metal particles supported on alumina, finely dispersed cobalt clusters inside zeolite pores are highly resistant to carbon deposition. Carbon deposits reduce the activation energy of CO hydrogenation to almost half, and the blockage of active sites by polymeric and graphitic carbons results in a significant decrease in CO hydrogenation activity. Hydrocarbon product distributions are hardly affected by carbon deposits, but a shift in selectivity of paraffins to olefins is observed. © 1991.