Hydrolysis And Photolysis Characteristics Of Pyriftalid

This article establishes and optimizes the detection method of pyriftalid in the aqueous residue, by this method we can get the pyriftalid’s hydrolysis and photolysis kinetic parameters and reveal the pyriftalid’s hydrolysis and photolysis characteristics.In the pyriftalid’s hydrolysis experiments, the writer selects the five representative pH buffer solutions (pH is5、6、7、8、9), pyriftalid in the pH7buffer solution is hardest to decompose, alkaline solutions and acidic solutions are easily decomposed for pyriftalid’s hydrolysis. The pyriftalid with the different initial concentrations’ hydrolysis experiments’ results are if the concentration of pyriftalid is higher then the hydrolysis half-life is longer. The half-lifes of pyriftalid in different kinds of water (river water, lake water, water, distilled water) are27.2d,30.0d,18.9d and47.3d, the pyriftalid half-life in field water is shortest and in distilled water is the longest. The half-life of the pyriftalid in the0.1%surfactant solution (Tween20, Tween60, Tween80, Span80, sodium dodecyl sulfate, mixed several surface active agents and the distilled water blank control) are48.1d,51.7d,55.9d,43.7d,43.9d,51.4d,52.6d. The pyriftalid’s hydrolysis experiments under the different temperatures (20℃,30℃,40℃) show that the high temperature is beneficial to the pyriftalid’s hydrolysis. Adding Cu2+can not significantly change the pyriftalid’s hydrolysis half-life.The high-pressure mercury lamp and xenon lamp as a light source’s experiments research the different light intensity, pH solutions, initial concentrations, organic solutions and adding surfactants in aqueous solution which can affect the pyriftalid’s photolysis rate. The results show in different pH solutions, pyriftalid’s photolysis half-life is pH5>pH7> pH9. Tween20, Tween60, Tween80, Span80are common surface active agents. The article researches their affection to the pyriftalid’s photolysis rate shows their photosensitizations. But when they are joined together reflecting light quenching. The experiments on pyriftalid’s photolysis half-life in organic solutions are indicating that fastest photolysis rate is ethanol and acetone is the slowest. Finally, Researching the two types of UV absorber’s(UV-p and UV-531) effect to the pyriftalid’s photolysis half-life.