College of Urban and Environmental Science, Northeast Normal University, Changchun 130024, China.
J Environ Sci (China). 2010;22(11):1774-8. doi: 10.1016/s1001-0742(09)60318-1.
HW-02 is a new organophosphates herbicide which is discovered and developed in China. The kinetics and mechanism of HW-02 photodegradation in the organic solvents were studied at 25 degrees C under the irradiation of ultraviolet light. The results showed that photochemical reaction of HW-02 in organic solvents such as n-hexane, methanol, dimethyl benzene and acetone under UV light could be well described by the first kinetic equation, and the photodegradation efficiency decreased with a order of n-hexane > methanol > xylene > acetone. The photodegradation efficiency constant of HW-02 in n-hexane, methanol, xylene and acetone were 4.951 x 10(-2), 3.253 x 10(-2), 2.377 x 10(-2) and 1.628 x 10-2 min(-1), and the corresponding half-lives were 13.99, 21.20, 29.15 and 42.56 min, respectively. By separation and identification of photoproducts using GC-MS, it could be concluded that HW-02 was photolyzed through ester cleavage, photo-dechlorination and photoisomerization of the molecule itself.
HW-02 是一种新型有机磷除草剂，由中国自主研发。本研究采用紫外光照射，在 25°C 下研究了 HW-02 在有机溶剂中的光降解动力学和机制。结果表明，HW-02 在正己烷、甲醇、二甲苯和丙酮等有机溶剂中的光化学反应可用一级动力学方程很好地描述，光降解效率随正己烷>甲醇>二甲苯>丙酮的顺序降低。HW-02 在正己烷、甲醇、二甲苯和丙酮中的光降解效率常数分别为 4.951×10(-2)、3.253×10(-2)、2.377×10(-2)和 1.628×10-2 min(-1)，相应的半衰期分别为 13.99、21.20、29.15 和 42.56 min。通过 GC-MS 对光产物进行分离和鉴定，得出 HW-02 是通过酯键断裂、分子本身的光脱氯和光异构化进行光解的。
