A novel electrochemically enhanced homogeneous PMS-heterogeneous CoFe2O4 synergistic catalysis for the efficient removal of levofloxacin

A novel electrochemically enhanced homogeneous-heterogeneous catalytic system was constructed by placing the prepared heterogeneous catalyst (CoFe2O4/NF) in parallel between the anode and the cathode for peroxymonosulfate (PMS) activation to remove levofloxacin (LVF) in this work. Over 90% of LVF could be effectively removed by the constructed system after 40 min's degradation. And the electrical energy consumption was only 2.51 kWh/m3, which was lower than 54.5% of the traditional electrochemical advanced oxidation process. Besides, the system broadened the response range of pH and overcame the inhibitory effect of alkaline conditions on degradation. These activities were mainly due to the high generation ability of free radical (SO4·-, ·OH and O2·-) and non-radical (1O2). And the SO4·- was found to be the main radical for LVF degradation. The high SO4·- generation ability was demonstrated to be resulted from the dual effects of synergy of CoFe2O4/PMS and enhancement of electrochemistry in EC/CoFe2O4/PMS system. In detail, electrochemistry could effectively promote the continuous circulation of Co2+/Co3+ and Fe2+/Fe3+ redox cycles on the surface of CoFe2O4 to enhance the activation of PMS, thereby generating SO4·-. This work can provide a promising and cost-effective approach to construct highly efficient organic pollutant degradation system.