乙羧氟草醚水解动态

Degradation Dynamics of Fluoroglycofen-ethyl in Water

采用气相色谱仪,建立了水中乙羧氟草醚残留量的分析检测方法,并在室内研究了其在不同温度、不同pH值缓冲溶液中的降解动态。结果表明:乙羧氟草醚在不同温度和不同pH值条件下的降解均符合典型的一级动力学规律。在同一温度下,其水解速率常数随着pH的升高而增大;在同一pH值条件下,温度升高,降解速率加快。在25℃时,乙羧氟草醚在pH值分别为9、7、5的缓冲溶液中的降解半衰期分别为85.6min、144.4h和12.2d;在50℃时,其在相应缓冲溶液中的降解半衰期分别为23.3min、13.4h和10.7d。研究表明乙羧氟草醚为易水解农药。

An analytical method for residue of fluoroglycofen-ethyl in buffer solutions was established by gas chromatography. The degradation in three different buffer solutions under various temperature was studied. The results showed that the degradation of fluoroglycofen-ethyl followed the first-order kinetics. The half-lives of degradation of fluoroglycofen-ethyl in three different buffer solutions with pH value of 5,7 and 9 were 12.2 d, 144.4 h and 85.6 min at 25 ℃,respectively,and were 10.7 d, 13.4 h and 23. 3 min at 50℃, respectively. The hydrolytic rate of fluoroglycofen-ethyl increased with the increasing of pH value and temperature in reaction medium.