Treatability of diclofenac and triclosan solutions by catalytic and photocatalytic oxidation processes

Abstract BACKGROUND In recent years, advanced oxidation processes (AOP) have gained importance as highly effective methods in the treatment of organic substances with toxic and permanent properties. Diclofenac (DCF) and Triclosan (TCS) pollutants, which are from the endocrine disrupting chemicals (EDCs) that were encountered in various aquatic environments such as inlet and outlet waters of treatment plants, surface waters, drinking water, groundwater and sediments were reported in the literature. In this study, mineralisation of DCF and TCS pollutants, which were the EDCs, were investigated by AOPs. The applied processes were O 3 , O 3 /UV, O 3 /ZnO, UV/ZnO, and O 3 /UV/ZnO. The studies were carried out at two different initial concentrations (5 and 10 mg/L), at 5 ppm ozone dose, 2 × 8 W UVC light, 0.1 g ZnO, in the original pH, and 30 min reaction time. RESULTS The highest COD and TOC removal efficiencies were determined in O 3 /UV/ZnO process as 82% COD, 71% TOC at 5 mg/L concentration for DCF pollutant and as 72% COD, 75% TOC at 10 mg/L concentration for TCS pollutant. For these process conditions, the ozone consumptions were determined 0.13 mgO 3 /mgCOD removed , 0.31 mgO 3 /mgTOC removed and 0.69 mgO 3 /mgCOD removed , 0.98 mgO 3 /mgTOC removed , respectively. The electrical energy per order values were found in the range of 12.33–20.88 kWh/m 3 for O 3 /UV/ZnO processes. Treatment costs of these processes were calculated in the range of 0.002 to 44.823 €/m 3 . CONCLUSION For the treatability of DCF and TCS pollutants, ozone‐based advanced oxidation processes, especially O 3 /UV/ZnO photocatalytic ozone oxidation process were determined as a feasible process. © 2024 Society of Chemical Industry (SCI).