Minimization of organic content in simulated industrial wastewater by Fenton type processes: A case study

Abstract

Pre-treatment of simulated industrial wastewaters (SIM1, SIM2 and SIM3) containing organic and inorganic compounds (1,2-dichloroethane, sodium formate, sodium hydrogen carbonate, sodium carbonate and sodium chloride) by oxidative degradation using homogeneous Fenton type processes (Fe 2+/H 2O 2 and Fe 3+/H 2O 2) has been evaluated. The effects of initial Fe 2+ and Fe 3+ concentrations, [Fe 2+/3+], type of iron salt (ferrous sulfate vs. ferric chloride), initial hydrogen peroxide concentration, [H 2O 2], on mineralization extent, i.e., total organic content (TOC) removal, were studied. Response surface methodology (RSM), particularly Box–Behnken design (BBD) was used as modelling tool, and obtained predictive function was used to optimize the overall process by the means of desirability function approach (DFA). Up to 94% of initial TOC was removed after 120 min. Ferrous sulfate was found to be the most appropriate reagent, and the optimal doses of Fe 2+ and H 2O 2 for reducing the pollutant content, in terms of final TOC and sludge production were assessed.