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 ⁶⁰Co-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) × 10⁹ dm³·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) × 10⁸ dm³·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.