Parametric optimization for the treatment of human urine metabolite, creatinine using electro-oxidation

The efficacy and durability studies of the dimensionally stable anode (DSA) have been carried out for the treatment of human urine metabolite, creatinine using electro-oxidation process. The influence of various input parameters such as current density, treatment time, pH and concentration of electrolyte on responses like % degradation and energy consumption were explained using Box-Behnken design. 85.41% pollutant degradation along with complete mineralization was achieved at optimum conditions like pH-(2.4), current density-(10.29 mA cm− 2), NaCl concentration-(0.75 g L− 1) and treatment time-(85 min). Interestingly, a treatment time of was significantly lower than the reported values with similar kind of advanced technologies. Further reduction in treatment time i.e. 60 min was achieved by incorporating synergistic effect through Photoelectrocatalysis for the same %degradation. The electrodes used were durable enough even after forty-five cycles as confirmed through SEM/EDS and Raman Spectra. Further, mineralization studies were carried out by measuring the reduction in COD (81.25%) and TOC (84.37%) along with generation of various ions such as nitrite, nitrate and ammonium ion under the optimized conditions. Based upon the detected intermediates analyzed through FT-IR and LC-MS, a degradation mechanism for creatinine has been proposed.