Fenton Catalyzed Degradation of Pesticide Containing Wastewater.

Abstract

Catalytic degradation of Diazinon containing pesticide wastewater using Fenton reagent was investigated at bench scale experiments. Synthetic pesticide wastewater was prepared using commercially available Diazinon pesticide. Initial physicochemical characterization of synthetic wastewater was carried out before the Fenton oxidation. Chemical Oxygen Demand (COD) and bi'ochemical Oxygen Demand (BODs) values of the 200 ppm synthetic pesticide wastewater were 698.2 ppm and 8.5 ppm respectively. Optimum Fenton reaction conditions for the pesticide degradation were determined by changing H2O2 and Fe2+concentrations and by controlling pH and the stirring time. COD removal efficiency was used to study the pesticide degradation. The COD removal efficiency of99 % was achieved at pH 3 with Fe2+ concentration 0.05 mo! dm-3 and H2O2 concentration 0.32 mol dm-3 after 60 minutes stirring time. Thin layer chromatographic studies and gas chromatographic studies showed complete degradation of the active component presented in the pesticide after the Fenton reaction. Fenton treated pesticide sample shows positive results for the qualitative phosphate test confirming the dissociation of phosphate group in Diazinon. Preliminary NMR studies also showed complete dissociation of the active component in the pesticide. The results of this study can be used to design a treatment process for real pesticide wastewater.