氟唑菌酰胺在土壤中的吸附、迁移及水中降解特性研究

发布时间：2018-02-26 06:11

  本文关键词： 氟唑菌酰胺 吸附 解吸 迁移 降解　出处：《西南科技大学》2017年硕士论文　论文类型：学位论文

【摘要】：通过室内模拟实验,探究了氟唑菌酰胺在土壤中吸附-解吸、迁移及水中降解特性。(1)优化了氟唑菌酰胺在水、土壤中的残留分析条件,方法的准确度和精密度均满足农药残留分析的要求。在0.05~100 mg.L-1范围内线性关系良好,线性相关系数为0.9999。水样中添加水平为0.1~1.0 mg.L-1,平均回收率为81.21%~84.56%,相对标准偏差为0.38%~0.85%。土壤中添加水平为1.0~10.00mg.kg-1,平均回收率为81.76%~100.45%,相对标准偏差为0.71%~4.27%。(2)氟唑菌酰胺在土壤中吸附遵循准二级吸附动力学,过程包含两个阶段,第一阶段吸附速率大于第二阶段。以初始浓度为0.5 mg.L-1为例,黄壤中两阶段KWM分别为0.753,0.213,紫色土中分别为0.456,0.160。(3)在黄壤、紫色土中属于弱吸附。Freundlich模型吸附常数Kf-ads值分别为7.276和3.437,有机质吸附常数KOM分别为25.008、11.814。解吸过程存在迟滞效应。滞后系数H分别为0.990,0.903。(4)根据《化学农药环境安全评价试验准则》,氟唑菌酰胺在两种土壤中属于中等移动,Rf值在0.322~0.472之间。(5)氟唑菌酰胺在水中降解过程符合一级动力学方程。中性条件更有利于降解,温度25℃时,pH 4、7、9的半衰期分别为81.7、35.3、55.8 d;温度升高,降解速率增大,pH 7时,5℃、25℃、35℃的半衰期分别为101.2、42.2、25.8 d。氟唑菌酰胺在土壤中弱吸附性,较强的迁移性,难降解性,使其容易迁移进入深层土壤,甚至地下水,较长时间稳定存在于水中,对地下水存在潜在危害。
[Abstract]:In this paper, the adsorption, desorption, migration and degradation of fluazolamide in soil were studied through laboratory simulation experiments. The analytical conditions of fluazolamide residues in water and soil were optimized. The accuracy and precision of the method meet the requirements of pesticide residue analysis. The linear relationship is good in the range of 0.05 mg.L-1. The linear correlation coefficient was 0.99999.The average recovery was 81.21 and 84.56.The correlation coefficient was 0.99999.The average recovery was 81.21 and 84.56.The relative standard deviation was 0.3810mg 路kg ~ (-1). The average recovery was 81.760.45mg 路kg ~ (-1), and the relative standard deviation was 0.71 ~ 4.27.2.The adsorption of fluoriomycin in the soil followed the standard deviation of 0.38 ~ 10.00 mg 路kg ~ (-1) 路kg-1.The average recovery was 81.76 mg 路L ~ (-1), and the relative standard deviation was 0.71% ~ 4.27 mg 路L ~ (-1). Quasi second order adsorption kinetics, The adsorption rate in the first stage was higher than that in the second stage. For example, the KWM of the two stages in yellow soil was 0.753U 0.213, and in purple soil was 0.456U 0.160.0.93) in the yellow soil, the initial concentration was 0.5 mg.L-1, respectively, in the yellow soil, the adsorption rate in the first stage was higher than that in the second stage. In purple soil, the adsorption constants of weak adsorption. Freundlich model were 7.276 and 3.437, and the adsorption constants of organic matter KOM were 25.008 and 11.814, respectively. There was hysteresis effect in the desorption process, and the hysteresis coefficient H was 0.990 and 0.903.44, respectively. The results showed that fluazolamide in the two soils was of moderate mobility R _ f between 0.32 22 and 0.472.) the degradation process of fluazolamide in water followed the first-order kinetic equation. Neutral conditions were more favorable for degradation. At 25 鈩，

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