The mechanisms and process of acephate degradation by hydroxyl radical and hydrated electron

The degradation process of acephate in aqueous solution with (•)OH and [Formula: see text] produced by (60)Co-γ irradiation and electron pulse radiolysis was studied in the present paper. In the aqueous solution, acephate reacted with [Formula: see text] and transformed to transient species which can absorb weakly in the wavelength range of 300–400 nm and decay very fast. According to the decay of hydrated electron, the reaction rate constant of [Formula: see text] and acephate is (3.51 ± 0.076) × 10(9) dm(3)·mol(−1)·s(−1). The transient species produced in the reaction of (•)OH and acephate do not distinctly absorb the light in the wavelength range of 300–700 nm, so the decay and kinetics of the transient species cannot determinedirectly. The competing reaction of KSCN oracephate with (•)OH were studied to obtain the reaction rate constant of (•)OH and acephate, which is (9.1 ± 0.11) × 10(8) dm(3)·mol(−1)·s(−1). Although acetylamide and inorganic ions were determined in the products of the reaction of acephate with (•)OH or [Formula: see text] , the concentration of inorganic ions in the products of the reaction of acephate with (•)OH is higher than that in the product of the reaction of acephate with [Formula: see text]. Moreover, there were sulfide in the products of the reaction of acephatewith [Formula: see text]. The degradation pathways of acephate by (•)OH and [Formula: see text] were also proposed based on the products from GC-MS.