The efficiency of conversion of coal in the coal-gasification process is increased by pre-treatment of the coal to increase the fluid-permeability thereof. The reagent used for increasing the coal permeability is recoverable in high yield. Pre-treatment of bituminous coal by this process makes it possible to gasify coals of this rank effectively, such coals previously having been gasifiable only at low conversion efficiencies. Pre-treatment with a permeability-enhancing reagent is also useful as a step in the process of dissolving coal.