Degradation of Nitrobenzene in an Aqueous Environment through Fenton-like Process Using Box–Behnken Design Method

Background & Aims of the Study: Recently, the advanced oxidation processes have received growing attention in industrial wastewater treatment. In this project, the degradation and mineralization of an aqueous environment containing nitrobenzene (NB) as the main carcinogenic contaminant were inspected by a Fenton-like process. In addition, the influence of operational variables, such as initial concentrations of H2O2, Ferric ion, and pH on the removal of NB was investigated. Materials and Methods: The Box-Behnken design (BBD) of experiments and the response surface methodology were applied to explore the effects of three independent variables on the response functions to get the optimum conditions. Analysis of variance (ANOVA) was used to determine the significance of the effects of independent variables on the response function. Different amounts of variables were optimized for the removal of NB in the Fenton-like processes. Results: At optimum conditions (H2O2 and Ferric concentrations of 15.33 and 1.30 mM, respectively, and a pH of 6.23) and after 30 min of reaction, the removal efficiency for NB and chemical oxygen demand (COD) were 99.0% and 56.7%, respectively. Conclusion: The Fenton-like process influenced the removal of NB; however, it could only remove the COD to some extent. The obtained results at optimized circumstances were outstanding from the environmental point of view.