The RSM-CCD Optimization of Fenton Process for Industrial Wastewater Treatment and Determination of Treatment Efficiency Using Some Biochemical Responses in Dreissena polymorpha

The study investigated antioxidant biomarkers in Dreissena polymorpha to evaluate the efficiency of Fenton process (FP) in Organized Industrial Zone Wastewater (OIZW) treatment. Antioxidant enzymatic activities, including superoxide dismutase (SOD) and catalase (CAT), glutathione peroxidase (GPX), non-enzymatic antioxidants (GSH) and the indicator of lipid peroxidation (TBARS) were measured in D. polymorpha in response to treated OIZW by FP. The performance of the FP has been optimized with response surface methodology (RSM). The optimum conditions (reaction time, and H2O2 and Fe2+ concentration) for OIZW by the FP process were determined. The results showed that the highest COD removal efficiency (83.94 %) was obtained when as Fe2+ concentration=402.35 mg/L, H2O2 concentration=4100.30 mg/L, and reaction time=10.10 min (desirability=1.000). SOD and CAT enzyme was decreased in the 1/25 diluted OIZW group compared to control group. CAT and SOD enzyme activities were increased after treatment compared to control groups. No statistically significant changes were observed in GSH levels and GPx activities. TBARS levels were increased 1/25 diluted OIZW exposure groups compared to the control group. TBARS levels were decreased after treatment. The results revealed that antioxidant parameters are useful biomarkers for determining the treatment efficiency of the FP.