HOMOGENEOUS RU-CO BIMETALLIC CATALYSIS IN CO2 HYDROGENATION - THE FORMATION OF ETHANOL

In the homogeneous Ru-Co bimetallic catalysis of the hydrogenation of CO2, the cobalt can partly replace the Ru without loss of productivity, it enhances the selectivity in ethanol and catalyzes the homologation to ethanol of the methanol resulting from the hydrogenation, by the Ru, of CO2. The most significant feature was found to be that the Co complex is stabilized by the Ru complex during the CO2 hydrogenation, in contrast to the Fe and Mo complexes. This stabilization suggests the formation of some stable Ru-Co mixed metal clusters during the hydrogenation catalysis, although there is some FT-IR evidence to the contrary. It was also shown that the presence of CO is not sufficient to stabilize the Co complex under such severe reaction conditions.