Fast pyrolysis bio-oil upgrading over noble metal catalysts

Catalysts play critical roles in hydrotreating and hydrocracking processes of upgrading biomass-derived bio-oil to drop-in fuels. The selectivity and deactivate of catalysts, however, still remain biggest challenge. By using ZSM-5, aluminum, and activated carbon as supports, different catalysts made up with Ru were prepared and tested in a bio-oil upgrading process. The catalysts’ performances were investigated and compared in term of surface properties. The results showed that the ZSM-5 based catalysts got more water phase because of its highest surface acidity. The alumina changed to aluminum hydroxide in the presence of water at the reaction conditions. Activated carbon based catalysts showed good catalytic performance with more hydrocarbons and less water phase content in the upgraded bio-oil. All of upgraded bio-oils were verified by chemical analysis using a GC-MS. Nonetheless, further study for the kinetics of catalytically upgrading bio-oil is recommended.