采用批量平衡试验的方法,研究了不同初始浓度的六氯苯在红壤和黄泥土表面的吸附与解吸特征.结果表明,六氯苯在红壤和黄泥土表面的吸附与解吸行为均可用Freundlich方程进行很好的拟合,其相关系数(R^2)在0.97-0.99之间,并表现为非线性特征.六氯苯在红壤和黄泥土上吸附的KF^ads值均小于其解吸的KF^des守值,说明六氯苯在这两种土壤表面的解吸表现为一定的滞后效应.随着初始浓度的升高,其滞后效应增强,两者呈线性相关.用不同方程对滞后系数H,ω和λ进行量化,发现不同浓度的六氯苯在土壤表面的解吸过程表现出正滞后效应.
Desorption characteristics of hexachlorobenzene(HCB) on two soil surfaces were investigated by using the equilibrium method in different initial concentrations. The results revealed that, adsorption and desorption isotherm of HCB on two soils were nonlinearity, which can be best described by Freundlich equations, and the correlation coefficient( R2 ) ranging from 0. 97 to 0. 99. The apparent sorption-desorption hysteresis was existed, because the KF^des were higher than KF^ads in two soils. Desorption of HCB from soils exhibited hysteresis at all concentrations, with higher concentrations showing greater hysteresis. Hysteretic efficiency was quantified with different parameter, that is H, ω and λ, and the positive hysteresis was found at different concentrations.