Black liquor from the Kraft pulping process to produce cellulose pulp contains lignin and sodium hydroxide, which are known to enhance the dissolution of coal. But no work has so far been done on the depolymerization of coals using black liquor as an additive. The addition of black liquor enhanced the coal conversion yield about 38.6% in the experiment. But the extent of the enhancement was lower than expected values from separate NaOH/coal and lignin/coal experiments.