新型农药丁烯氟虫腈的光降解研究

STUDY ON PHOTO-DEGRADATION OF NEW PESTICIDE BUTYLENE FIPRONIL

为了解丁烯氟虫腈在液体中的降解趋势,采用液液萃取气相色谱-质谱(GC-MS)测定水中丁烯氟虫腈含量,研究丁烯氟虫腈在紫外光和太阳光照射下,在不同液体中的降解动态和降解产物.研究结果表明,在紫外光照射下,丁烯氟虫腈在水、0.01 mol.L-1氯化钙溶液、甲醇、乙酸乙酯以及正己烷中的降解过程均符合一级反应动力学,27℃下丁烯氟虫腈溶液的降解半衰期分别为2.69 h、2.67 h、6.30 h、5.63 h和1.52 h,在丙酮中几乎不降解;丁烯氟虫腈在紫外光照射下的降解速率要快于在阳光照射下的降解速率,随着温度的升高,光解速率增加,随着pH值的增加或者降低,降解速率有所降低.采用气相色谱质谱仪对丁烯氟虫腈的3种光产物结构进行了初步鉴定,以期对丁烯氟虫腈的科学应用提供理论依据.

A method was developed for the determination of butylene fipronil residues in aqueous solution with liquid-liquid extraction and gas chromatography/mass spectrometry（GC/MS） in order to investigate the photo-degradation dynamic of butylene fipronil in different solutions under ultraviolet（UV） light and sun light.The results of the study showed that the photo-degradation of butylene fipronil could be described by first-order kinetics in water,0.01 mol · L-1CaCl2 solution,methanol,ethyl acetate and hexane under UV light.The half life of photo-degradation was 2.69 h,2.67 h,6.30 h,5.63 h and 1.52 h respectively at 27 ℃.But it hardly degraded in acetone.The effect of light source,temperature and pH value on degradation rate was also studied.The results showed that the photo-degradation rate under UV light was faster than that under sun light,photo-degradation rate were accelerated with temperature,but slowed when pH value was increased or decreased.Three photo-degradation products of butylene fipronil were indentified with（GC/MS）.