Upgrading bio-oil model compounds phenol and furfural with in situ generated hydrogen.

Bio-oil produced from prolysis process of biomass cannot be directly used for transportation fuels, because of the poor quality. Catalytic hydrogenation is then used to upgrade bio-oil to engine-grade fuel. However, external H₂ addition may not be cost effective to obtain high quality of oil. In this work, the feasibility of in situ hydrogen generation and hydrodeoxygenation is studied. Formic acid and acetic acid were selected as compounds for hydrogen generation by reforming reaction. Furfural and phenol were used as model bio-oil compounds and were hydrogenated by in situ generated hydrogen from these acids using commercial Pd/C and Nickel based catalysts, RZ409. The reaction was performed in a batch-scale reactor at 300°C for 3 h. The amount of H₂ generation depended on the type of catalyst and substrate used. For example, 1 mol formic acid yielded 0.46 mol H₂ (46% yield) and 0.46 mol CO₂ with Pd/C, while it produced only 0.15 mol H₂ and 0.15 mol CO₂ with RZ490. The Furfural and phenol could be hydrogenrated and translated to different byproducts with in situ generated H_2, with some byproducts identified. The results provide a clear rationale for utilization of in situ generated H₂ for future bio-oil upgrading to reduce external H₂ usage. © 2014 American Institute of Chemical Engineers Environ Prog, 33: 751-755, 2014 [ABSTRACT FROM AUTHOR]