Removal of Selected Micropollutants from Synthetic Wastewater by Electrooxidation Using Oxidized Titanium and Graphite Electrodes

Abstract

Micropollutants cover a variety of compounds that mainly originate from the pharmaceutical and agricultural sectors. Even at trace concentrations, the discharge of micropollutants into water bodies pose a serious threat to the environment and human health. Their removal from wastewaters at treatment plants before their discharge into the environment has become one of the leading topics of research. Physical, chemical, and biological treatment methods have been listed in the literature for efficient removal of a variety of pollutants. In this study, seven micropollutants, namely 4-tert-octylphenol, atrazine, 2,4,6-trichlorophenol, fluoxetine, estrone, penconazole, and di-n-octyl phthalate, are spiked into municipal simulated synthetic wastewater and treated by a laboratory-scale electrooxidation (EO) system using oxidized titanium and graphite electrode as anode and cathode, respectively. Sensitive determination of the selected micropollutants by gas chromatography-mass spectrometry (GC-MS) before and after treatment is performed after their pre-concentration using an eco-friendly switchable solvent liquid-phase microextraction method (SSLPME). The pH value, applied current, and reaction period are optimized to enhance the removal efficiency of micropollutants. Results show that the highest removal efficiency of all micropollutants is obtained at pH 3, 20 min reaction period, and 3 A applied current. The operational costs are also investigated in this study.