Applications of doped mixed metal oxide anode for the electro-oxidation treatment and mineralization of urine metabolite, uric acid

Abstract

Removal of nitrogen-based contaminants present in urine wastewater has become a considerable matter of concern because of its potentially harmful effects on human health and can cause alterations to aquatic life. Hence to avoid its dangerous effects, electro-assisted technology was employed for the voidance of this metabolite with the doped-mixed metal oxide. The influence of various input factors such as time, pH, current density and NaCl dose on treatment efficiency in terms of percent degradation and energy consumption were evaluated using response surface methodology. Electrolysis results showed that 95.35% degradation of uric acid was achieved at optimized conditions. In addition, to reduce the treatment time further, attempts have been made by incorporating dual effect i.e. Photoelectrocatalysis. The anode used for multiple runs were proven to be effectively stable through XRD and SEM/EDS. Analysis of treated uric acid solution was validated in terms of COD (92%) and TOC (89%) reduction. The transformation products of uric acid were identified through LC–MS. Based on these intermediates and literature survey, an oxidative mechanism for uric acid has been proposed. The total operating cost for electro-oxidation treatment process is found to be 0.18 $/m3.