Electrochemical oxidation of sulfadiazine antibiotic using boron-doped diamond anode: application of response surface methodology for process optimization

Abstract

Electrochemical oxidation and process optimization of sulfadiazine antibiotic were investigated in a batch electrochemical reactor using boron-doped diamond (BDD) anode. Reaction conditions were operated at 200–1,000 mg/L sulfadiazine concentration, 0–8 g/L supporting electrolyte (NaCl), 4–20 mA/cm2 current density, and 25–45°C reaction temperature at 120 min reaction time. Process optimization was accomplished through response surface methodology in central composite designed experiments. Optimum operating conditions were determined under specified cost-driven constraints at 13.4 mA/cm2 current density, 618 mg/L sulfadiazine concentration, 3.6 g/L electrolyte concentration, and 36°C reaction temperature. In a specific batch run at response surface-optimized conditions, the responses for sulfadiazine removal, COD removal, EOX, and energy consumption were achieved as 100.0%, 95.5%, 0.0617, and 94.3 kWh/kg CODr, respectively. Relative error values in this optimization study for the electrochemical oxidation of sulfadiazine antibiotic using BDD anode were obtained below 2%.