1,1,2,2-四氯乙烷在土壤中的吸附解吸研究及解吸滞后的新型模型模拟

采用室内实验方法,研究了1,1,2,2-四氯乙烷（1,1,2,2-tetrachloroethane,1,1,2,2-TeCA）在4种土壤上的吸附和解吸行为,并用一种新型解吸模型——＂双元平衡解吸（Dual-EquilibriumDesorption,DED）模型＂对其解吸行为进行了预测。结果表明,1,1,2,2-TeCA在4种土壤上的吸附符合传统的线性吸附模型,lgKoc的平均值为1.86;解吸行为则表现出明显的滞后现象,解吸后的lgKo（c平均值约为4.88）显著大于初始值,且与吸附相污染物的初始浓度、土壤性质无相关性。DED模型比传统线性模型能更好地拟合TeCA在土壤中的解吸滞后现象。

Sorption and Desorption of 1,1,2,2-Tetrachloroethane in Soils and New Model Prediction of Desorption Hysteresis

In this study,the sorption and desorption of 1,1,2,2-tetrachloroethane（TeCA） in four soils were investigated.The desorption data was modeled using a new desorption model-＂Dual-Equilibrium Desorption（DED） model＂.The results indicated that the sorption of TeCA agreed well with the conventional linear sorption isotherm and the mean value of lg Koc was 1.86.However,the desorption exhibits significant hysteresis.The value of lg Koc after desorption（with mean value of 4.88） was significantly higher than that before desorption.The value was independent of the original concentrations of adsorbed TeCA in soils and of soil properties.In comparison with the traditional linear model,the desorption hysteresis of TeCA in soils could be predicted well with the DED model.