Abstract: “The UV/H2O2 process is optimized for slaughterhouse wastewater (SWW) treatment using a continuousflow photoreactor with effluent recycle. A four factors at five levels central composite design (CCD) with response surface methodology (RSM) is used to maximize total organic carbon (TOC) removal and minimize H2O2 residual. The effects of the influent TOC concentration, H2O2 dosage, feed flow rate, and effluent recycle on the photolytic treatment of SWW are also investigated. Statistical modeling is used to predict the percent TOC removal and H2O2 residual as the response variables. Results show that recycle ratio is significant in minimizing the H2O2 residual and its cross-factor interactions with other variables demonstrate a significant effect on percent TOC removal. The statistical models are validated at the optimum operating conditions based on the results of the design of experiments (DOE). The model predictions are found to be in agreement with observed values, indicating that the”

Keywords: slaughterhouse wastewater (SWW), advanced oxidation processes (AOPs), effluent recycle, UV/H2O2 , central composite design (CCD), design of experiments (DOE)