(675b) Co-Liquefaction of Lignocellulosic Biomass and Heavy Oil Residue By One-Step Reaction Using Supercritical Organic Solvents

Co-processing of biomass and biofuels with conventional petroleum feedstock using already installed oil refinery processes seems to be a promising alternative for bio-oil production. In this study, simultaneous one-step co-liquefaction of wood biomass (microcrystalline cellulose or oil palm empty fruit bunch fibers (EFB)) and vacuum residue (VR) was carried out by using sub- and supercritical solvents such as m-xylene, n-dodecane, tetralin and decalin.

The co-liquefaction performance with/without the Fe₃O₄ catalyst and initial H₂ pressure in each solvent was evaluated with conversion, liquid yield, coke formation and product distribution, and was compared with the results of only VR liquefaction. A simulated distillation (SIMDIS) gas chromatography method was used for the analysis of liquid products. In the absence of catalyst and H₂ at 450ºC, the co-liquefaction of VR and biomass could reach up to 88.5% while the coke amount did not exceed 5%. The Fe₃O₄ catalyst significantly contributed to suppressing coke formation and thus increased liquid product yield in all solvents (especially in m-xylene and n-dodecane) if H₂ was also introduced to the reaction. The conversion in co-liquefaction could be improved only by VR upgrading reaction, and EFB was more favorable than microcrystalline cellulose in liquid yield and coke suppression. The obtained liquid products were completely soluble in low polar solvents.