Oxidation of Palm Oil Mill Effluent Using Hydrogen Peroxide and Catalysed by UV Light/Zinc Oxide

Abstract

Abstract The amount of palm oil mill effluent produced annually in Malaysia has been on the increase increasing and causing degradation of the environment due to poor disposal owing to incomplete treatment. Various studies have been carried out in order to study ways to improve the condition of the wastewater characteristics before discharging into any water body. This study determined the efficacy of photocatalytic treatment method using hydrogen peroxide, zinc oxide and ultraviolet light. A variety of operating conditions were investigated such as the effect of pH, hydrogen peroxide dosage, amount zinc oxide, ultraviolet light irradiation and contact time in order to determine the optimum condition for the treatment method. Kinetics of degradation was also conducted. For UV/H2O2 treatment process, under optimum conditions, it was found that the highest COD and colour removal efficiency was 41.9% and 38.3%, respectively. For UV/ZnO treatment process, under optimum conditions, the highest COD and colour removal efficiency was 37% and 85%, respectively. For UV/H2O2/ZnO treatment process, under optimum conditions, the highest COD and removal efficiency was 60.2% and 91.6%, respectively. This study found pH 11, H2O2/COD molar ratio of 5, 0.4 g of zinc oxide, 200 rpm at 4 h reaction time as the desirable operating condition for removal of COD and colour from the palm oil mill effluent.