In-situ upgrading of biomass pyrolysis vapors: Catalyst screening on a fixed bed reactor

► Fifteen catalysts for the in-situ upgrading of biomass pyrolysis vapors were studied. ► Catalysts' effect on selectivity and oxygen content of the bio-oil was investigated. ► ZrO2/TiO2 and ZSM-5 formed aromatics and effectively reduced bio-oil oxygen content. ► Deoxygenation took place by CO, CO2 and H2O formation reducing bio-oil yield. ► Coke formation bound carbon and resulted in low C/O ratios in the liquid product.