Oxidation of diazinon by homogeneous fenton process

Abstract

The degradation of aqueous diazinon from an aqueous solution using H₂O₂/Fe²⁺ process is performed in a 1L batch chemical reactor. The extent of diazinon degradation (20 mg/L) has been investigated from a known initial pH solution, temperature and catalyst type (Fe²⁺, Fe³⁺) and for various initial concentrations of diazinon, H₂O₂ and Fe²⁺. The degradation efficiency was obtained (90.82% and 90.63%) at pH 3 and 4 of the initial solution respectively while catalyst type and reaction temperature have a slight impact on the final degradation of diazinon. Efficiency of diazinon removal can be enhanced by increasing initial H₂O₂ concentration in the range of 70 to 150 mg/L and initial Fe²⁺ concentration in the range of 2 to 5 mg/L. The highest degradation efficiency obtained was 90.95% at initial diazinon concentration of 10 mg/L, H₂O₂=150 mg/L and Fe²⁺ = 5 mg/L. This study proved that Fenton process can be used for pretreatment of pesticide wastewater contaminated by diazinon before a biological treatment.