Abstract Modeling analysis based on a statistical physics theory was used to explain the adsorption of Ag+ and Hg2+ on layered double hydroxides (LDH) functionalized with anions CO32−, NO3−, S52− and MoS42−. Theoretical adsorption models assuming different types of functional groups on LDH surface were tested and compared. A statistical physics model based on two active sites for the adsorbate binding was the best option to characterize and interpret the removal of investigated heavy metals on LDH. Modeling results showed that the total adsorption capacities at saturation ranged from 112 to 631 mg/g and from 110 to 638 mg/g for Ag+ and Hg2+, respectively. LDH functionalized with anion MoS42− was the best adsorbent for the removal of both metal ions. It was also demonstrated that the anionic functionalities and the oxygen-containing groups of LDH contributed in different extent for the adsorption of Ag+ and Hg2+. Statistical physics parameters suggested a multi-ionic and endothermic adsorption caused by physical and chemical interactions. Finally, the adsorption mechanism was macroscopically explained via the calculation and analysis of thermodynamic potentials.

中文翻译：

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通过统计物理模型了解 Ag+ 和 Hg2+ 在功能化层状双氢氧化物上的吸附机制

摘要 基于统计物理理论的建模分析用于解释 Ag+ 和 Hg2+ 在被阴离子 CO32-、NO3-、S52- 和 MoS42- 官能化的层状双氢氧化物 (LDH) 上的吸附。测试和比较了假设在 LDH 表面具有不同类型官能团的理论吸附模型。基于吸附质结合的两个活性位点的统计物理模型是表征和解释 LDH 上研究的重金属去除的最佳选择。建模结果表明，饱和状态下的总吸附容量分别为 Ag+ 和 Hg2+ 的 112 至 631 毫克/克和 110 至 638 毫克/克。用阴离子 MoS42- 功能化的 LDH 是去除两种金属离子的最佳吸附剂。研究还表明，LDH 的阴离子官能团和含氧基团对 Ag+ 和 Hg2+ 的吸附有不同程度的贡献。统计物理参数表明由物理和化学相互作用引起的多离子和吸热吸附。最后，通过热力学势的计算和分析从宏观上解释了吸附机理。