氯吡嘧磺隆的水解动力学研究

Hydrolysis Kinetics and Mechanism of Halosulfuron-methyl

为了明确氯吡嘧磺隆对环境的影响和在水中降解的动力学参数,采用固相萃取-高效液相色谱法,通过室内模拟试验研究了氯吡嘧磺隆在不同自然水体、不同p H缓冲溶液中的水解动态。结果表明:氯吡嘧磺隆在碱性条件下水解最快,酸性条件次之,半衰期分别为0.7天和8.9天。而在中性条件下最缓慢,半衰期为14.6天,说明氯吡嘧磺隆在中性环境中稳定性较好。氯吡嘧磺隆在4种不同类型水中的水解速率顺序为:湖水>河水>稻田水>蒸馏水。研究结果为指导氯吡嘧磺隆的合理使用和环境风险评估提供了科学数据。

To explicit the dynamics parameter of hydrolysis of halosulfuron-methyl and the influence of halosulfuron-methyl on environment, the dynamics of halosulfuron-methyl hydrolysis were studied in laboratory simulation experiments at different pH, different water by efficient HLPC-UV. The results showed that the hydrolysis of halosulfuron-methyl was faster in basic media than under acidic conditions, the corresponding half-lives were 0.7 d and 8.9 d. However, the hydrolysis was the slowest in neutral conditions and the half-lives was 14.6 d, indicating that halosulfuron-methyl was stable in neutral water. The hydrolysis rates in 4 different types of water were： lake water 〉river water〉field water 〉 distilled water. The results could provide scientific basis to guide the reasonable use of halosulfuron-methyl and the future environmental risk assessments.