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Introduction Organophosphorus pesticides (OPPs) are one of the most widely used classes of agricultural pesticides introduced in 1970 s . Advanced oxidation processes (AOPs) constitute a promising technology for treatment of waters containing persistent organic compounds with high toxicity and low biodegradability Advanced Oxidation reaction are based on generation of hydroxyl radical (OH*) or direct photodegradation . Because of “ Adsorption Capacity ” the use of Carbon forms like AC, Graphene and CNT are extensive in now a days for water purification & other Environmental Applications . Materials and methods Studies performed in aqueous matrix containing 1 ppm of individual pesticide . Batch experiments carried out in a Pyrex reactor with 500 mL of the pesticide aqueous solution . The pesticides aqueous solution was subjected to UV irradiation alone, UV/ H 2 O 2 and UV/H 2 O 2 /Fe 2 + . A maximum of four hours of irradiation was performed in all the experiments . Pesticides were desolved in 1 L of DW and absorbed in 1 g of Graphene Oxide . Analysis : U - V Visible, GC - MS and GC – ECD . Results and discussion On UV irradiation exposure, phorate , dimethoate and chlorpyrifos degraded upto 89 % , 33 % and 19 % respectively within 30 minutes . UV/ H 2 O 2 enhanced the rate upto 97 % , 90 % and 25 % for phorate , dimethoate and chlorpyrifos respectively UV/H 2 O 2 /Fe 2 + shows to 95 % , 83 % and 50 % respectively within 30 minutes . O rder of treatment efficiencies of chlorpyrifos , dimethoate and phorate obtained for the studied AOP . UV/Fenton> UV/H 2 O 2 > UV alone >Fenton, UV/H 2 O 2 > UV/Fenton> UV alone >Fenton and UV/H 2 O 2 > UV/Fenton > UV . alone >Fenton respectively . Fe 2+ + H 2 O 2 Fe 3+ + OH - + OH * Fe 3+ + H 2 O Fe (OH) 2+ + H + Fe(OH) 2+ hν Fe 2+ + OH * Conclusions AOP techniques appears to be an effective method in destroying OPPs from water. The studies shows that phorate and dimethoate is easy degrade as compared to chlorpyrifos in aqueous media As mentioned with EPA highly hazardous OPP that widely used is phorate so, these technique can be applied for the degradation. Interaction b/w GN - W - P are stronger compared to GN - P. Graphene Nanocomposites for Removal of Organophosphates (OPPS) in Aqueous Media and Their Degradation in Water using Advanced Oxidation Process (AOP) Dhananjay Tripathi 1 , Supriy Verma 2 , J. B. Valenzuela 3 and D. K. Tiwari 3 . 1 Institute of Environment & Sustainable Development, 2 Department of Chemistry; Banaras Hindu University, Varanasi-221005, India. 3 Centro de Nanociencias y Nanotecnología, Universidad Nacional Autónoma de México, Ensenada, B.C. 22800, México. Fig. 1 Spectroscopic analysis of GO & RGO Fig. 2 Technique used Fig. 3 %degradation of OPP Table 1 GN-W-P interaction Pesticides Mol. Formula MW (g/mol) WS @ RT Ad. Cap. (mg/g) Chlorpyrifos C 9 H 11 Cl 3 NO 3 PS 350.59 (2 mg/L) 1100 Diemethoate C 5 H 12 NO 3 PS 2 229.26 (25 g/L) 700 Phorate C 7 H 17 O 2 PS 3 260.38 ---- 1400 0% 20% 40% 60% 80% 100% 30 60 120 240 %degradation Time (min) Trends of Degradation UV Exposure Chlorpyrifos Dimethoate Phorate 0% 50% 100% 30 60 120 240 %degradation Time(min) Trends of Degradation UV+Fenton reagent Chlorpyrifos Dimethoate Phorate 0% 50% 100% 30 60 120 240 %degradation Time(min) Trends of Degradation UV+H 2 O 2 Chlorpyrifos Dimethoate Phorate
