(699c) Selective Hydrogenation of Acrolein On Supported Silver Catalysts: Particle Size and Alloying Effect

Selective hydrogenation of α, β–unsaturated aldehydes to unsaturated alcohol is of commercial and research interest. Kinetic control is required since the hydrogenation of the C=C bond is thermodynamically favored. Selective hydrogenation of acrolein was studied on a series of silica-supported silver catalyst samples with different particle sizes from small (d = 0.8 nm) to large (d = 9.0 nm). Ag particle sizes were estimated by EXAFS and confirmed by TEM. The catalytic reaction was carried out in gas phase in a plug flow microreactor and the effluent was analyzed by a downstream GC. Kinetics studies were done at low conversion to avoid mass transfer limitations. Our results show that the reaction is structure sensitive and that the selectivity may be related to the different exposed planes as the nanoparticles change size. Various Ag-based alloy catalysts were synthesized as well. Results will also be presented for various Ag alloy catalysts in an effort to fine tune selectivity.