Electrochemical degradation of chemical wastewater by anodic oxidation process

The wastewaters produced in chemical production contain large numbers of persistent organic pollutants, posing potential adverse impacts to aquatic ecosystem and human health. In this work, the electrochemical degradation of organic pollutants in chemical wastewater belonging to Sunny wealth chemicals (Linyi, Shandong Province) was conducted using anodic oxidation process. Three commercially available anodes (Pt, boron-doped diamond (BDD) and Ti-Ru-Sn ternary oxide (Ti/RuO₂-SnO₂)) were chosen to investigate the effect of several primary operating parameters, such as electrolyte composition, electrolyte concentration and applied current density. Total organic carbon (TOC) was detected as reference parameters to assess the performance of anodic oxidation. The experimental results show that BDD anode exhibited excellent oxidation capacity for degradation of organics in chemical wastewater, achieving over 30% removal efficiency in all cases within 4 h. TOC removal efficiency of 52% was obtained with BDD anode in 4 h of reaction time at applied current density 30 mA cm^-2, NaCl concentration 0.05 mol L^-1; nevertheless, less than 45 % of removal was achieved with Pt and Ti/RuO₂-SnO₂ anode under the same conditions. (paper)