Effective degradation of ammonia nitrogen wastewater by novel three-dimensional residual charcoal particle electrode

This paper presents a novel electrocatalytic system for degrading ammonia nitrogen (NH₄⁺-N) wastewater, constructed using gasification fine slag residual carbon (GFS-RC) particle electrodes in a three-dimensional electrocatalytic oxidation reactor. The physicochemical properties of the GFS-RC particle electrodes were characterized by XPS, SEM and XRD, among other analytical techniques. Experimental conditions were optimized via response surface methodology (RSM). Under optimal conditions (particle concentration: 1.4 g/L, pH 8.43, electrolysis voltage: 16 V), the NH₄⁺-N removal efficiency reached 95.99 %. Kinetic analysis demonstrated that NH₄⁺-N degradation followed first-order kinetics across all tested parameters. Energy consumption analysis revealed that the three-dimensional electrocatalytic system exhibited significantly lower energy usage (0.156 kWh/g) compared to conventional two-dimensional systems (0.201 kWh/g). Furthermore, the potential degradation mechanism of NH₄⁺-N was systematically elucidated. This study provides a strategic framework for advancing three-dimensional electrocatalytic oxidation systems in NH₄⁺-N wastewater treatment, enhancing solid waste valorization, and developing cost-effective carbonaceous particle electrodes.