Efficient treatment of landfill leachate using an electrochemical ceramic membrane filtration system: Chlorine-mediated oxidation

Efficient removal of contaminants from landfill leachate remains to be a major challenge, calling for novel technologies for advanced treatment of those high-salinity wastewaters. In this work, an iridium-decorated electrochemical ceramic membrane was fabricated via magnetron sputtering deposition for the treatment of landfill leachate. The electrochemical ceramic membrane filtration (ECMF) system achieved 70.8 ± 1.5 % of chemical oxygen demand (COD) and 31.7 ± 2.8 % of total nitrogen under hydraulic retention time (HRT) 60 min and membrane flux 50 L/(m2 h) during 14-d operation. Furthermore, the ratio of biochemical oxygen demand (BOD) to COD in the effluent was increased to 0.56 in comparison to that of the influent (0.24), indicating the increase in the biodegradability of the effluent. The reactive chlorine species generated in the system were mainly responsible for the pollutant removal in this system, efficiently oxidizing the humic substances and reducing the aromaticity of the contaminants. The energy consumption and current efficiency of the ECMF system were 49.3 kWh/ kg COD and 37.4 % at 20 mA cm−2, respectively. The results of this study highlight the potential of using the ECMF system for efficient treatment of high-salinity wastewater.