Donor solvent interactions during coal liquefaction

Two UK bituminous coals (Cresswell and Point of Ayr) were liquefied using ternary solvents composed of 9,10-dihydroanthracene, 1-methylnaphthalene and a variety of aromatic and heteroatomic compounds. Coal conversion yields were measured in terms of THF- and quinoline-soluble material, following reactions in a stirred batch autoclave under standard conditions of 1 h at 400 °C, and with normalized amounts of hydroaromatic components present as solvent. Enhancement of coal conversion yields was observed for two aromatic compounds (fluorene and pyrene) and for 1- and 2-naphthol. Different mechanisms were established for the synergistic effects of fluorene and pyrene. Antisynergism was observed while using a secondary alcohol, 9-fluorenol, as a solvent component. In binary solvents composed of a hydroaromatic species and 1-methylnaphthalene, 9,10-dihydroanthracene was found to be a more efficient hydrogen donor than tetralin and the efficiency was observed to vary monotonically with the donatable hydrogen concentration of the solvent. © 1989.