基于非平衡热力学理论的黏土多组分重金属吸附模型

黏土垫层土颗粒的吸附特性是控制溶质运移的重要关键因素,进而影响对防渗屏障长期服役性能的准确评估。在传统单组分吸附模型的基础上,基于非平衡热力学和Ziegler最大耗散率原理,通过构建弥散型自由能函数和弥散型耗散率函数,采用连续介质力学方法建立了非理想状态体系下适用于多组分重金属离子的非平衡态吸附模型。所建模型预测的多组分重金属离子吸附行为与已有试验结果吻合度较好,对比分析结果表明:所建非平衡态吸附模型能够正确揭示多组分重金属离子在黏土中的吸附动力学机制。

Adsorption model for multi-component heavy metal ions on clay based on non-equilibrium thermodynamics

The adsorption behavior of clay particles is the key factor to control the solute transport, which can further affect the accurate evaluation of the long-term service performance of the seepage prevention barrier. Based on the single-component adsorption model, the theory of non-equilibrium thermodynamics and Ziegler's principle of maximal rate of dissipation, a non-equilibrium adsorption model for multi-components under non-ideal system is established by using the continuum mechanics method through setting up the dispersion-type free energy function and dissipation rate function. The proposed model is employed to describe the adsorption process of heavy metal ions. The results show that there is a good agreement between the model and experimental results, and it is indicated that the proposed non-equilibrium adsorption model can correctly reveal the kinetics mechanism of adsorption process for multi-components on clay.