The role of activated carbon and disinfection on the removal of endocrine disrupting chemicals and non-steroidal anti-inflammatory drugs from wastewater

Endocrine disrupting chemicals (EDCs) and non-steroidal anti-inflammatory drugs (NSAIDs) are two important groups of emerging pollutants due to their toxicological and chemical characteristics and their persistent detection in the aquatic environment. Wastewater treatment plants are a significant pathway for their transfer to the water courses. It is well evidenced that these chemicals are only partially removed through biologically treatment of wastewater and therefore being detected in secondary effluents. This work focuses on the evaluation of the efficiency of two well established disinfection technologies (chlorination and UV irradiation) along with UV/H₂O₂ and powdered activated carbon (PAC) to remove these chemicals from biologically treated wastewater. Based on the results it is shown that appreciable removal efficiencies due to chlorination should be expected for most of the target compounds, whereas this was not the case for ibuprofen and ketoprofen. With the exemption of diclofenac and ketoprofen direct UV irradiation did not efficiently removed target compounds for UV doses usually applied for disinfection purposes. The application of advanced UV treatment through the addition of H₂O₂ although resulted in increased removal of the target compounds is not sufficient for moderate UV and H₂O₂ doses to achieve satisfactory removal efficiencies. PAC use resulted in sufficient removal of target compounds although high PAC doses were required for some chemicals. Comparison of Freundlich isotherms of this study with those of other studies, derived employing water samples, suggested that the water matrix along with the target compounds concentration range can significantly affect the outcome of the experiments.