Influence of reaction parameters on titanium anode electro-oxidation coupled with filtration system for leachate treatment

Abstract

Landfill leachate contains a complex mix of organic and inorganic pollutants that pose serious environmental challenges. To address this, an integrated electro-oxidation (EO) system using titanium anodes, combined with a dual-stage filtration unit, was developed for efficient leachate treatment. A compact EO reactor with fully submerged electrodes was designed in this study to enhance electrochemical reaction efficiency and maintain thermal stability. The specific electrode configuration and integration with filtration represent a practical enhancement over conventional EO setups. Key operational parameters of EO, including reaction time, applied voltage, number of electrodes, and electrode spacing were systematically assessed. Optimal EO performance was achieved at 80 min, 30 V, four electrode sets, and 3 cm spacing, with removal efficiencies of 99 % (turbidity), 82 % (colour), 99 % (chemical oxygen demand, COD), 90 % (total suspended solids, TSS), and 96 % (ammoniacal nitrogen). ANOVA results confirmed the statistical significance of all parameters. The system also demonstrated improved energy efficiency, with lower energy consumption and higher COD removal than other reported EO systems. Integration with sand and activated carbon filtration further enhanced removal efficiencies, achieving ≥ 95 % for all key parameters. These findings highlight the potential of the optimized EO-filtration system as a scalable and effective solution for sustainable leachate treatment.