Thermal treatment in liquefaction solvent was applied to Victorian brown coal as pretreatment for suppression of the scale formation during coal liquefaction. In order to improve reactivity of pretreated coal. the effects of hydrogenated solvent, hydrogen gas and catalyst were investigated. Hydrogenated solvent was effective to suppress the reduction of coal reactivity. Pretreatment with hydrogen gas and catalyst (pyrite) seemed effective to increase the coal reactivity.
