毒死蜱有毒代谢物3,5,6-TCP在土壤中的吸附-解吸研究  

Adsorption-desorption Behavior of Chlorpyrifos Toxic Metabolite 3,5,6-TCP on Soils

作　　者：孙宝利[1] 曾希柏[1] 

机构地区：[1]中国农业科学院农业环境与可持续发展研究所农业部农业环境与气候变化重点开放实验室,北京100081

出　　处：《农业环境科学学报》2011年第6期1114-1120,共7页Journal of Agro-Environment Science

基　　金：国家科技支撑计划(2007BAD89B03);国家级公益性科研院所基本科研业务费资助

摘　　要：应用OECD106批平衡方法,研究了毒死蜱的有毒代谢物3,5,6-TCP在6种典型土壤中的吸附-解吸行为。结果表明：Elovich方程、双常数方程和抛物线扩散方程能较好地拟合3,5,6-TCP在第四纪红土、黑土、黄壤和褐土中的吸附动力学过程,而对紫色土和潮沙土的拟合度较低（拟合相关系数小于0.85）;应用Freundlich方程和线性方程拟合第四纪红土、黑土、黄壤和褐土的经验常数nfads均小于1（非线性吸附）,而紫色土和潮沙土的nfads值则接近于1（线性吸附）;3,5,6-TCP在6种土壤中解吸的滞后系数H值均大于1,即解吸速率大于吸附速率。6种土壤对3,5,6-TCP的吸附常数Kfads从1.37-6.74μg1-n·fmLn·fg^-1,吸附系数Kd值从0.50-1.30mL·g^-1,其中第四纪红土和黑土对其吸持力较强（Kd〉1）,因而更应注意环境安全;其他4种土壤的Kd值则均小于1,淋溶风险较大。On the basis of the OECD Guideline 106, the batch equilibrium experiments were carried out in six kinds of soils to investigate adsorption and desorption processes of 3,5,6-TCP（3,5,6-trichloro-2-pyridinol）, which were an ionizable organic compound and one kind of toxic metabolites of chlorpyrifos. The results showed that the adsorption kinetic behaviors of the 3,5,6-TCP in the quaternary red soil, black soil, yellow loam soil and brown soil were best described by the Elovich equation, Double Constant model and Parabolic diffusion model, while it could not be well described by above models（Correlation coefficient0.85） in the purple and loam sand soils. Either linear or Freundlich sorption isotherm could describe the sorption behaviors of the 3,5,6-TCP in six kinds of soils with the values of the nfads 1（non-linear sorption） in the quaternary red soil, black soil, yellow loam soil and brown soil and nfads ≈1（linear sorption） in the purple and loam sand soil. The apparent adsorption-desorption hysteresis was found and the 3,5,6-TCP desorption rates in six kinds of soils were faster than that of adsorption with the value of H1. The adsorption constant Kfads and Kd in six kinds of soils varied form 1.37-6.74 μg1-nf·mLnf·g^-1 and 0.50-1.30 mL·g^-1 respectively. It was concluded that the quaternary red and black soils had the strongest capacity of adsorption, while the other four soils had a great leaching risk.

关 键 词：毒死蜱 3 5 6-TCP 吸附 解吸 风险 

分 类 号：X592[环境科学与工程—环境工程]