Amin Ahmadpour - National Petrochemical Company, Petrochemical Research and Technology Company - Mahshahr Centre,Mahshahr, Iran
Alireza Bozorgian - Department of Chemical Engineering, Mahshahr Branch, Islamic Azad University, Mahshahr, Iran;
Ali Eslamimanesh - Department of Process Engineering, Faculty of Chemical Engineering, Tarbiat Modares University, Tehran,Iran;
Amir H. Mohammadi - Discipline of Chemical Engineering, School of Engineering, University of KwaZulu-Natal, Howard CollegeCampus, King George V Avenue, Durban, ۴۰۴۱, South Africa;

In this research, the characteristic oxygen demand (COD) of a sample from low-salt effluent of the olefinunit of a petrochemical complex has been reduced using photocatalytic technique in ultraviolet light.The waste stream investigated herein is the olefin unit effluent of Maroon petrochemical complexlocated in southern Iran. For this purpose, a discontinuous slurry photo reactor was designed and builtupfor laboratory studies. Various tests including XRD and SEM have been performed in order toevaluate and to confirm the structural properties of the employed photo catalysts. Furthermore, theeffluent COD removal efficiency of the process has been investigated as a function of the commoneffective parameters in photo-catalytic degradation such as photo catalyst concentration, aerationintensity, oxidation of hydrogen peroxide (H۲O۲) and PH. The statistical results show that by decreasingPH and increasing catalyst concentration, the rate of COD reduction increases. Moreover, a furtherdecrease of COD is observed at high PHs following an increase in the amount of auxiliary oxidant. Inorder to optimize the treatment process, the COD removal efficiency has been maximized and,consequently, the optimal values of the studied factors have been obtained. The final removalefficiencies achieved through the optimization process are in the range of ۷۴ to ۷۷%.

Wastewater treatment; Photo-catalytic treatment; COD; Titanium oxide, Petrochemicaleffluent