莠去津在5种不同土壤中的吸附行为及影响因素

Adsorption Behavior and Influencing Factors of Atrazine in Five Different Soils

采用批平衡法,室内模拟5种土壤对莠去津的吸附特性,并就土壤的不同组分对吸附的影响进行分析。结果表明土壤对莠去津的吸附是动态平衡过程,24 h达到吸附平衡,最佳土水比例为1∶5。莠去津在5种土壤中的吸附可以用Linear、Langmuir、Freundlich 3种模型拟合,且Freundlich模型最优。土壤对莠去津的吸附为轻微非线性吸附,吸附系数(Kf)为1.16~4.68,在土壤中表现为难吸附,莠去津解吸附系数(Kfdes)与吸附系数(Kfads)相当,易解吸。5种土壤有机质含量和pH值是影响莠去津吸附的主要因子。

The batch balance method was used to simulate the adsorption characteristics of atrazine in five kinds of soil,and the effects of different components of soil on adsorption were analyzed. The results showed that the adsorption of atrazine in soil was a dynamic equilibrium process, and the adsorption equilibrium was reached at 24 h. The optimum soil/solution ratio was 1∶5. The adsorption of atrazine in five kinds of soil could be fitted by the Linear, the Langmuir and the Freundlich models and the Freundlich model was optimal. The adsorption of atrazine in soil was slightly nonlinear adsorption, and the adsorption coefficient(Kf) was 1.16-4.68, which was difficult to adsorb. The desorption coefficient Kfdes of atrazine was equivalent to the adsorption coefficient Kfads, which was easy to desorb. The organic matter and pH of soil performed dominating factors during the adsorption-desorption.