Conversion of biomass-derived syngas to alcohols and C2 oxygenates using supported Rh catalysts in a microchannel reactor

The capability of a microchannel reactor for synthesis of alcohols and C2+ oxygenates from biomass-derived syngas was explored. Supported Rh catalysts were selected to integrate with a microchannel reactor for this study. The focus of the present research was to investigate the impact of reaction variables, including temperature, pressure, H2/CO ratio, and activation procedures, on the activity and product selectivity of supported Rh catalysts. It was observed that the formation of undesired product, methane, can be suppressed under conditions of low temperature, high pressure, and low H2/CO ratio. Interestingly, different catalysts responded differently to reduction–oxidation cycle (RedOx) treatment. A hybrid catalyst system containing CuZnAl and Rh-Mn/SiO2 exhibited continued increase in activity after RedOx treatment. When Rh-Mn/SiO2 catalyst was coated on a FeCrAlY metallic felt substrate and subsequently integrated into a microchannel reactor, a significant enhancement in specific activity was obtained, which highlights strong process intensification potential for commercial application.