Raw coal containing sulfur impurities and water is ground in a vapor-tight extraction zone in contact with a combustible sulfur solvent at an elevated temperature. An extraction mixture slurry is formed which includes a liquid component comprising the solvent and sulfur impurities and a solid component comprising the comminuted, extracted coal. The liquid and solid components of the slurry are separated. At least a portion of the liquid component is preferably treated to separate sulfur. The liquid component is recycled to the extraction zone.If the solid slurry component has an undesirably high pyrite content, it is then reacted with a reagent to decompose the pyrites to water-soluble sulfur compounds and the reaction mixture is washed with water.