Chemicals from direct coal liquefaction

The target of coal liquefaction is to produce substitutes for petroleum distillate fuels having an atomic ratio of 1.8-2.5, more particularly, replacements for gasoline and diesel fuel. The desire to liquefy coal into petroleum substitutes, particularly lighter liquid fuel, stems from the abundance of coal and increasing demand for transportation fuels that are currently produced predominantly from the crude petroleum through a series of refining processes. Coal and heavy crude can be converted into light liquid hydrocarbons through several routes, such as liquid hydrocarbons produced through pyrolysis, direct hydrogen addition, and gasification of CO and H ₂. Coal liquefaction produces C1-C3 gaseous hydrocarbons, naphtha, and middle distillates (kerosene and gas oil) as petroleum substitutes. A number of coal liquefaction catalysts have been developed in Japan. Among them, natural limonite ore, which contains γ-FeOOH, is an excellent catalyst.