Decomposition of 2,2′,4,4′,5,5′-hexachlorobiphenyl with iron supported on an activated carbon from an ion-exchange resin

► A novel catalyst from ion-exchange resin called IRFe-C had a high Fe concentration. ► PCBs could be destroyed by IRFe-C under an atmosphere of air or N2. ► In situ adsorption-decomposition process was achieved in PCB wastes disposal process. ► The functional groups on IRFe-C influenced the decomposition effect of PCBs. ► Reactive characteristics of Cl atoms on benzene rings followed para > meta > ortho.