Bioregeneration of granular activated carbon in simultaneous adsorption and biodegradation of chlorophenols

► Bioregeneration efficiencies of 4-CP and 2,4-DCP loaded GAC were determined. ► Adsorbed 4-CP and 2,4-DCP were successfully tracked during bioregeneration. ► Adsorption of intermediates of 4-CP and 2,4-DCP was of little significance. ► Optimum conditions for higher bioregeneration efficiency were obtained.