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[Display omitted] • Ti/SnO 2 -ZnO anode was used to degrade perfluorooctanoic acid. • The properties of three composite electrodes were comparad. • Ti/SnO 2 -ZnO electrode has good stability and electrochemical oxidation. • The optimal removal rate of perfluorooctanoic acid reached 86.17%. Perfluorooctanoic acid (PFOA) was a persistent pollutant that exists in many environmental media. In this research, two kinds of metal additive (Zn, Ru) were applied to Titanium substrate to obtain suitable coating materials for PFOA degradation in sewage. Three compound materials were compared to confirm the removal efficiency of PFOA under different electrolytic conditions and the stability of coating, and the Ti/SnO 2 -ZnO was determined to the most suitable anode. The cyclic voltammetry (CV) and electrochemical impedance spectra (EIS) were employed to analyze the modification properties of Ti/SnO 2 -ZnO anode at the same. The impact of different working conditions included three factors: pH, current density, and initial concentration. When Ti/SnO 2 -ZnO anode was evaluated, in order to achieve optimum effects (86.17%), it should be proved that pH was 6, current density was 16 mA/cm2 and initial concentration was 10 mg/L. The excellent stability of electrode was detected by five parallel experiments. Besides, the experiment determined the degradation kinetics, and it further explored the removal mechanism, as well as the pathways of PFOA degradation by Ti/SnO 2 -ZnO anode through the analysis of decomposition intermediates. The results showed that PFOA degradation was a directly mineralization and underwent complex reactions, observing the pseudo-first-order kinetic equation appropriately. [ABSTRACT FROM AUTHOR]

[Display omitted] • Heavy metals and microplastics were treated through interpenetrating bipolar plate electrocoagulation (IBPE). • Changes of current density and initial pH value were proved to affect the experimental results. • Reaction mechanism of IBPE reactor for removing heavy metals and microplastics was analyzed. • IBPE reactor could effectively remove heavy metals and microplastics in secondary effluent of WWTP. In this study, the mixed pollutants of microplastics and heavy metals from secondary effluent of wastewater treatment plant (WWTP) were removed by interpenetrating bipolar plate electrocoagulation (IBPE) reactor. Heavy metals and microplastics in the wastewater were simultaneously removed during the experimental process with high removal efficiency. The influences of current density, initial pH and reaction time on the removal rate were analyzed. When the current density was 12 mA / cm2, the initial pH was 6 and the reaction time was 20 min, the optimal removal efficiency of heavy metals and microplastics were obtained with removal rates of 95.16% and 97.5%, respectively. Under the condition of different current densities, the change of removal rate with time was fitted through mathematical model. The complexation forms of heavy metals and surface groups of microplastics were analyzed through pseudo-voltammetry curve. The operation cost of removing microplastics and heavy metals through IBPE reactor was 0.91 $·L−1 under the optimal experimental conditions. The experimental results suggested that this process reduced the potential harm of microplastics and heavy metals to aquatic organisms and human beings. The IBPE could be applied as a clean technology for simultaneous removal of microplastics and heavy metals from secondary effluent of WWTP. [ABSTRACT FROM AUTHOR]