Removal of heteroatom containing species in coal liquid distillates from South Banko coal by catalytic hydrotreatment over NiMo supported alumina catalyst

Coal liquid distillates ranging in the boiling point from naphtha to gas oil fractions tends to contain more heteroatoms such as nitrogen and oxygen than the corresponding petroleum product. Hydrotreatment of South Banko coal liquids (SBCL) was performed over commercially available NiMo/Al₂O₃ catalysts. The effect of reaction conditions such as temperature, contact time, and amount of catalyst on heteroatom removal was examined. HDS, HDN, and HDO reactivities of some heteroatoms containing species were studied. Most of sulfur species in SBCL were thiophenes and benzothiophenes. Pyridines, aniline quinolines, and indoles were found as nitrogen, while phenols, benzofurans, and dibenzofuran were as oxygen compounds. Pyridines showed high reactivity, however, anilines and quinoline were much less reactive. At high HDN conversions, the majority of the compounds remaining in the hydrotreated products were alkylated anilines.