Abstract: A method and apparatus for rendering PCB virulence-free is provided. The PCB to be treated is pre-heated with exhaust heat before it is introduced into a combustion furnace to facilitate the reaching of its boiling point, and the pre-heated PCB is caused to ascend through a layer of mineral particles disposed in the furnace, the mineral particles being of a porous multi-element mineral, the furnace interior and particularly the mineral particle layer being pre-heated to a temperature above 1,100.degree. C. from a different heat source. During consecutive reaction processes of gasification, dissociation and combustion of PCB brought about as PCB ascends through the mineral particle layer, the thermal dissociation into benzene ring and chlorine and further combustion of benzene ring are promoted by the catalytic actions of adsorption to mineral particle's large porous surface, catalytic cracking of multi-element oxides present in arranged fashion on the pore surface of mineral particles and surface combustion.