Detoxification of azinophos methyl using gamma radiation mediated advance oxidation process and investigation of degradation products by HPLC and GC-MS

摘要

Gamma radiolytic degradation of azinophosmethyl was studied in water and methanol separately, using ~(60)Co as a radiation source under varied experimental conditions. Solution of azinophos-methylwas prepared in pure methanol at concentration of 50 μg ml~(-1), irradiated at gamma dose of 1 to 7 kGy and high performance liquid chromatography (HPLC) coupledwith diode array detector was used to monitor the extent of degradation along with numbers of degradation products. At dose of 7 kGy ≥ 99% of azinophos-methyl was degraded. The degradation occurred by interaction of CH_3O? and H? radicals generated by the radiolysis of high purity methanol while in water by ?OH radical. The degradation in water was increased by 30% than in methanol due the high oxidation potential of ?OH while keeping the gamma ray dose constant at 3 kGy. The generated degradation products were identified using GC-MS and their possible transformation pathways are proposed. It is suggested that use of ionization radiations can be an effective and efficient tool for the removal of organophosphate pesticides in waste water.