LIQUID-PHASE HYDROGENATION OF CINNAMALDEHYDE OVER SUPPORTED RUTHENIUM CATALYSTS - INFLUENCE OF PARTICLE-SIZE, BIMETALLICS AND NATURE OF SUPPORT

Hydrogenation of cinnamaldehyde was studied over supported Ru based catalysts. The influence of particle size, bimetallic formulation and nature of support on activity and selectivity to the desired product, cinnamyl alcohol, was investigated. Ru particle size had a pronounced effect on both TOF and selectivity. Larger Ru particles showed higher selectivity to cinnamyl alcohol, as well as higher TOF. Addition of Sn, Fe, Ge, Sb, Zn and Ag as a second metal improved both activity and selectivity. Ru-Sn/Al2O3 showed sustained improvement in selectivity, even at higher conversions, probably due to the presence of Ru-Sn(delta+) sites and/or due to the electron transfer from Sn to Ru. ZrO2 was found to be the most effective support in terms of selectivity. Possible reasons for this behaviour of ZrO2 are delineated.