Co-Processing of Heavy Residue Oil and Biomass Using Supercritical Organic Solvents

The use of biomass as energy resources can increase energy security and reduce the need to use fossil fuels because it is abundant in most countries. Furthermore, utilization of biomass has received significant attention as a renewable energy source. Co-processing of biomass or biofuels with petroleum feedstock using conventional oil refinery processes seems to be an attractive alternative for the fuel production because the infrastructure investment can be saved by utilizing present facilities. In this study, co-processing 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 hydrocarbon solvents. The effects of Fe₃O₄ catalyst and hydrogen on the co-processing performance were evaluated in terms of residue conversion, coke formation and product distribution. In addition, the results were compared with the results of only VR upgrading. The co-processing of VR/EFB could achieve a residue conversion of 86.4 wt. % with only 0.8 wt. % of coke formation at a specific operating condition and solvent. In the presence of H₂, the Fe₃O₄ catalyst contributed toward suppressing coke formation. The liquid products were completely soluble in the applied solvents. It implied that the products consisted of soluble compounds in low polar solvents.