Electrochemical Combustion of Insecticides Endosulfan and Deltamethrin in Aqueous Medium Using A Boron-Doped Diamond Anode

Disposal of agricultral wastewater containing enosulfan and deltamethrin by electrochemical methods has been studied in this paper. The degradation of insecticides enosulfan and deltamethrin in aqueous medium of pHi range 5.8-6.2 has been comparatively studied by anodic oxidation using a boron-doped diamond (BDD) anode. A number of experements were run on a laboratory scale and the resulte are reportude here. GC and chemical oxygen demand measurements were conducted to study the reaction kinetics of two insecticides mineralization. The experimental results showed that the electrochemical process was suitable for almost completely removing COD, due to the production of hydroxyl radicals on the diamond surface. In particular, the COD removal follows a pseudo first-order kinetics and the apparent rate constant increased with applied current, while it is almostun affected by concentrations of pesticides and pH. Under optimal experimental conditions of temperature (T=25 °C), supporting electrolyte NaCl (1 g/L) and current density (i.e. 60 mA cm-2), 81% of COD was removed in 2 h electrolysis for deltamethrin, with 11 kWh(kgCOD-1), and 7.6 kWh(kgCOD-1) for endosulfan.