HYDROGENATION OF CARBON DIOXIDE ON SIRAL ALUMINOSILICATES MODIFIED WITH COBALT AND PALLADIUM

Abstract

The reaction of hydrogenation of CO2 in flow mode at atmospheric pressure on Siral aluminosilicates with 1, 10, and 40 wt.% SiO2 and containing Co and Co-Pd has been studied. The synthesized catalysts were characterized by XRD and EPR spectroscopy. It has been established that on catalysts containing only cobalt, at a reaction temperature of ≤ 300oC, practically only methane is formed, and at a reaction temperature of T ≥ 300oC, methane and no more than 1% CO are formed. It is shown that with an increase in the SiO2/Al2O3 ratio, a decrease in the methane yield is observed. The introduction of palladium into the composition of the Co/Siral catalyst stimulates the formation of methanol, the yield of which increases with an increase in the reaction temperature and reaches its maximum value at a reaction temperature of 500°C for the Co,Pd/Siral-10 catalyst. The mechanism of the reaction of CO2 hydrogenation to methanol and the role of palladium in this reaction are discussed. Keywords: carbon dioxide, hydrogenation, methane, methanol, Siral, Pd, Co.