IntroductionThe aliphatic and aromatic organic compounds present in ref-inery wastewater are a major source of aquatic environmentalpollution (Wake, 2005). The petroleum refineries use hugeamount of water in refining crude oil and subsequently gen-erate high volume of wastewater. Due to rapid increase indemand for oil worldwide, the wastewater effluent will conti-nue to rise and ultimately be discharged to main water sewer2014in the vicinity (Doggett and Rascoe, 2009; Marcilly, 2003). Therefinery wastewaters vary in composition depending on typeof crude oil, refining processes configuration, and procedures.The COD levels of refinery wastewater are generallybetween 100 and 600 mg l−1(WBG, 1999). Due to extreme tox-icity of contaminants in refinery wastewater, there is a needto develop an economical technique to remove the pollutantsfrom the effluent. The refinery wastewater is not suitablefor photo-degradation unless passed through pretreatment.