Comparison of the Efficiency of Simultaneous Application of UV/O3 for the Removal of Organophosphorus and Carbamat Pesticides in Aqueous Solutions

A vast variety of pesticides are used for agricultural pests in Iran. The release of these persistent organic pollutants. into water supplies leaves adverse effects on both the environment and public health. Advanced oxidation processes have been used recently for pesticide removal. In this research, the combined UV/O3 process has been investigated for the removal of organophosphorus pesticides (Diazinon, Chlorpyrifos), Carbamate pesticides (carbaryl). In this survey, samples have been prepared by adding given concentration (1, 5, 10, 15, 20 mg/L) of the pesticides to deionized water. The samples at separation periods were exposed to the combined UV/O3 (UV=50-200 Wm-2 and O3 = 1g hr-1)in a bath reactor at different pH levels (6, 7, 9) and for different contact times (0.5,1,1.5,2 hr) and the removal efficiencies were determined. Residual concentrations were determined using GC/MS/MS and HPLC. Based on the results, increasing pH reduced pesticide concentration and increased contact time had a direct effect on enhancing removal efficiency. The combined UV/O3 process was found to have a high efficiency (>80%) in degrading both halogenated Organophosphorus(Chlorpyrifos) and non- halogenated Organophosphorus (Diazinon) pesticides. Its removal efficiency for degrading carbamate pesticide (Carbari) was found to be >90%. Based on our results, this method may be suggested for the removal of pesticides from aqueous solutions