苄嘧磺隆和芘在土壤中的吸附解吸行为

吸附是外源有机污染进入土壤后首先发生的最重要的过程，直接影响着有机物的生物可利用性。采用完全混合法研究了苄嘧磺隆和芘在土壤中的吸附一解吸动力学特征以及等温吸附解吸行为。结果表明，（1）苄嘧磺隆和芘在土壤中的吸附-解吸动力学过程存在两段行为，即初期快速反应阶段和经过一段时间后的慢速阶段，动力学特征表明供试有机物8h内能达到吸附-解吸平衡；（2）在试验浓度范围内，线性方程能很好地描述苄嘧磺隆和芘在土壤中的吸附解吸行为；（3）苄嘧磺隆和芘在土壤中存在解吸迟滞现象，解吸并不完全是吸附的可逆过程，土壤中存在不可逆吸附室是造成解吸滞后的主要原因。

Sorption-desorption Behavior of Bensulfuron-methyl and Pyrene in Soil

Adsorption is the initial process when the exterior organic pollutants enter the soil, which influences directly the bioavailability of organics in soil The sorption-desorption behavior and its kinetics of Bensulfuron-methyl （ BSM ） and Pyrene （PYR） in soil as well as the isothermal sorption and desorption behavior were studied using completely mixing method. The results showed that ： （ 1 ） the sorption-desorption kinetics of BSM and PYR in soil included two phases, a speed reaction phase initially and a slow reaction phase followed. The kinetics showed that the testing organics could reach the sorption-desorption equilibrium in eight hours. （2） Within the testing concentration range, the linear equation described well the sorption-desorption behavior of BSM and PYR in soil （3） There was a phenomenon of desorption delaying for BSM and PYR in soil, the sorpfion is not a complete reversible process of desorption. The existence of irreversible sorption room in soil was the major cause of desorption delaying.