Photodegradation of metamifop using alumina-graphene nanocomposite

The issue of toxic water pollution caused by excessive use of agrochemical products has arose significantly over last few decades. The frequently used of herbicide metamifop causes the release of the toxic phenolic hydrocarbon group with the properties low biodegradable has rendered negative impacts on environment and human health. Therefore, photocatalytic degradation that classified as one of Advanced Oxidation Process (AOP) is able to create powerful hydroxyl radicals (-OH) that triggered by UV light to degrade targeted toxic organic pollutants in wastewater in the presence of photocatalyst. Thus, the study on the efficiency of the photocatalytic degradation towards metamifop was determined as a function of the metamifop loading (Sppm and 10 ppm), alumina-graphene (A1103-G) nanocomposite loading (10 mg and 20 mg) and oxygen loading at 2 L/min. The overall process was conducted in laminar flow chamber with UV lamp and continuously stirred using a magnetic plate for 3 hours. Analyticalmethods was determined using UV-Vis Spectrophotometer at initial (0 min) and final (180 mins) of the process. The maximum percentage degradation of91.61 % was obtained at 5 ppm of metamifop in the presence of 20 mg A1203-G nanocomposite photocatalyst under 3 hours of UV irradiation. Metamifop removal was enhanced up to 98.97 % by the effect of oxygen loading at 5 ppm of metamifop in the presence of 20 mg AlzO3-G nanocomposite photocatalyst under UV irradiation. It was also revealed that lower concentration of metamifop, higher dosage of photocatalyst beyond the optimum level and also presences of electron acceptors (O2) have significant positive effect on metamifop degradation efficiency. The study has proven that photocatalytic degradation process was a reliable method to reduce metamifop in contaminated water resources.