Treatment of Pharmaceutical Industry Wastewater by PhotoelectroFenton Oxidation

Abstract

The use of Photoelectro-Fenton oxidation to treat real pharmaceutical effluent is an attractive option for the elimination of complex and persistent organic contaminants. This advanced oxidation process combines the electrochemical generation of highly reactive hydroxyl radicals (OH• ) with the photochemical degradation of by-products, resulting in the efficient removal of pharmaceutical compounds from wastewater. In the Photoelectro-Fenton process, an appropriate anode material, such as BDD or DSA, is used to generate OH• radicals through the electrochemical oxidation of Fe2+ ions. The addition of a small amount of Fe2+ and H2O2 facilitates the Fenton reaction, leading to the production of additional OH• radicals in the solution. The presence of these OH• radicals ensures the effective oxidation of pharmaceutical pollutants, which are often resistant to conventional wastewater treatment methods. The use of UV or sunlight irradiation further enhances the Photoelectro-Fenton process by promoting the photodecomposition of intermediate by-products formed during the oxidation process. This simultaneous electrochemical and photochemical degradation mechanism provides synergistic effects, resulting in enhanced degradation and mineralization of pharmaceutical compounds. Studies have demonstrated the successful application of Photoelectro-Fenton oxidation for the treatment of real pharmaceutical wastewater, showing significant removal efficiencies for a wide range of pharmaceutical compounds, including antibiotics, analgesics, and hormones. Additionally, the process has been shown to effectively degrade recalcitrant by-products and reduce the overall toxicity of the wastewater. However, it is important to consider factors such as optimal pH, Fe2+ and H2O2 dosages, irradiation intensity, and reaction time to achieve optimal treatment efficiency. Furthermore, the cost-effectiveness and scalability of the Photoelectro-Fenton process need to be evaluated for its potential implementation in large-scale wastewater treatment facilities.