Hydrotreatment of lignocellulosic biomass derived oil using a sulfided NiMo/gamma-Al2O3 catalyst

Bio-oils derived from lignocellulosic materials have poor properties for use as fuels and cannot be blended with transportation fuels. Hydrotreating is an effective method for eliminating contaminants and saturating double bonds. This article is one of the few that report the hydrotreatment of a biomass-derived oil over a sulfided NiMo/gamma-Al2O3 catalyst and the deactivation of the catalyst. The results confirm that hydrotreatment is an effective technology for improving the quality of bio-oil. The total acid number of the upgraded bio-oil decreased from 23 mg KOH g(-1) (raw bio-oil) to 2 mg KOH g(-1). Oxygenated functional groups are removed, light liquid products are generated and carbon double bonds are saturated. The catalyst can become deactivated at a high operating temperature due to severe coke deposition. The deactivated catalyst was studied by using multiple analytical methods such as TEM, XRD, BET and TPO to study the deactivation pathways.