敌百虫和敌敌畏在黄河水体沉积物上的吸附机理

Mechanisms for Sorption of Trichlorphon and Dichlorvos on Yellow River's Sediment

研究了黄河水体沉积物对有机磷农药敌百虫和敌敌畏的吸附特性及机理.结果表明,沉积物对黄河水中敌百虫和敌敌畏的吸附符合Freundlich等温式和Langmuir等温式,是表面吸附和分配作用共同作用的结果.对表面吸附和分配作用在沉积物吸附敌百虫和敌敌畏的相对贡献率进行了定量描述,它们均为浓度的函数,敌百虫的吸附作用以表面吸附为主,而敌敌畏的吸附作用以分配作用为主.

The sorption mechanisms of trichlorphon or dichlorvos on Yellow River's sediment from the water of Yellow River at pH 8.10 are determined. It is found that the sorption isotherms of trichlorphon and dichlorvos on Yellow River's sediment are typically nonlinear,and the isotherms follow approximately Freundlich or Langmuir equation. Both the adsorption on the surface of the Yellow River's sediment and the partition between the solid phase and the water from Yellow River are the mechanisms of the sorption of trichlorphon and dichlorvos on Yellow River's sediment,the former is the predominants mechanism for trichlorphon and the latter is the predominant mechanism for dichlorvos. Furthemore, the relative contributions of both mechanisms to the whole sorption are dependent on the equilibrium concentration of trichlorphon or dichlorvos.