Studies Of Cinnamaldehyde Hydrogenation And Benzyl Alcohol Oxidation Over Supported Au Catalyst

With the development of modern society, a lot of resources and fossil energy areconsumed, the environmental pollution has become more and more serious, so peopleare trying to find a practical way to solve these problems. As an effective approach,developing new environmentally friendly catalytic materials and routes opens newspace for making full use of resources and reducing energy consumption. Amongthem, developing environmentally friendly technology of heterogeneous catalysis isone of the key methods to develop green chemistry.In this thesis, supported Au catalysts prepared by deposition-precipitation methodwere used for the selective hydrogenation of cinnamaldehyde and selective oxidationof benzyl alcohol. It was found that the metal-metal and metal-support interactionspromote the catalytic performance of the catalysts in the above reactions. Meanwhile,a lot of characterization techniques were employed to investigate the physical andchemical properties, structural features of Au catalysts to establish a relationshipbetween the catalyst structure and catalytic properties. The main results are asfollows.In the first part of this thesis, we synthesized highly dispersed and uniformCu-Au/SiO2bimetallic catalyst via an ammonia-evaporation-deposition-precipitationmethod. The resultant Cu-Au catalysts exhibited higher activity for thecinnamaldehyde hydrogenation compared with monometallic Cu and Au catalysts.Meanwhile, we also found metallic particles were highly dispersed on the surface ofthe support via various characterization techniques and a key reason of the highactivity of the Cu-Au/SiO2catalyst was ascribed to the synergistic effect of Cu andAu species.Secondly, we have designed and synthesized Au-CeO2@SBA-15catalyst andtested their activity and stability in the benzyl alcohol oxidation reaction. In theAu-CeO2@SBA-15catalyst, a high density of metal-metal oxide catalytic activecenter were formed by introducing CeO2into Au@SBA-15catalyst, which greatlyenhanced the catalytic property of Au catalyst. On the other hand, the Aunanoparticles were uniformly distributed in the pore structure of SBA-15. The confinement effect of the ordered pore structure of SBA-15enables the enhancedcatalytic activity and stability of the catalyst.