Coal liquefaction by colloidal iron sulphide catalyst

Abstract Taiheiyo coal, which was treated with an aqueous solution of dodecyltrimethylammonium chloride, adsorbed colloidal iron sulphide prepared from FeS0 4 · 7H 2 O and Na 2 S · 9H 2 O in aqueous media. The adsorbed colloidal iron sulphide was much more effective as a catalyst for the liquefaction of the coal itself than the usual powder-type iron sulphide. Thus in differential thermal analysis under hydrogen, the coal with 0.35wt% adsorbed colloidal iron sulphide gave an exothermic peak at 401 °C, which was ≈20 °C lower than when using the powder-type iron sulphide. The coal was smoothly hydrogenated at 450 °C to give a yield of ≈60% liquid products.