ACTIVE SPECIES ON COKED SILICA-ALUMINA CATALYST

The rapid, initial temperature rise attending oxidation of coked silica-alumina catalysts is due to a highly reactive material residing on the coke surface. The active species is formed in the coking process and is present even after a mild prevolatilization treatment in nitrogen; but it may be removed or rendered inactive by pretreatment under vacuum or in nitrogen at high temperature. A hydrogen-rich coke layer on the exterior of the basic coke particle is believed to be responsible for the effect observed. © 1969, American Chemical Society. All rights reserved.