Electrocatalytic Oxidation of Nanofiltration Concentrated Landfill Leachate with High-efficiency Ti/RuO2-IrO2-Pt 8% Anode

Abstract

The treatment of nanofiltration concentrate has always been a critical technical challenge in the application of membrane technology for landfill leachate treatment. This study attempts to address this challenge using electrocatalytic oxidation technology. A Pt-modified Ti/RuO₂-IrO₂ anode was synthesized using a solution method. The results show that Pt was uniformly dispersed within the Ru-Ir composite oxide phase, and Pt doping induced the formation of numerous disordered and mismatched lattices on the electrode coating surface. The interaction between Pt and the RuO₂-IrO₂ system can enhance the stability of the ternary composite electrode, improve electron transport efficiency, and reduce surface resistance of the electrode coating, thereby increasing the efficiency of chemical reactions. In the treatment of nanofiltration concentrate of landfill leachate, it was found that under conditions of a current density of 20 mA·cm⁻², electrode distance of 0.5 cm, and pH = 5, the removal rates of COD, TOC, and NH₄⁺-N were 93.5%, 46%, and 98% respectively, with an energy consumption of only 0.66 kWh·(kg TOC)⁻¹. After 20 repeated experiments, the Ti/RuO₂-IrO₂-Pt 8% anode also demonstrated good stability and catalytic activity.