Abstract: The molecular thermodynamic model established by Hu, Xu and Prausnitz was extended to the gas solubility in electrolytic solutions. The influence of ion charge on the Helmholtz energy of fluid mixtures was taken into account by considering the interactions between the charge of ions located in the first coordination shell and the dipole or induced dipole of the central solute molecule. The contribution of the ions outside the first coordination shell can be neglected owing to the symmetrical distribution of the positive and negative ions with respect to the central solute molecule. The model in this paper includes a correlation equation for the effective hard sphere diameter of ions and the Paulings crystal diameter, σ = ησcrycysl, where η= - 6.645 + 747.2511/T + 2.95392 × 10-2T- 5.05798 × 10-5T2 + 3.2431 × 10-8 T3, for T>453.15K, η= 1.021. The results of calculations for 78 systems of gas solubilities in 1-1 type electrolytic solutions indicate that this model can predict the Henrys constants of gases in electrolytic solutions over a wide temperature range and a wide concentration range for electrolytes with the use of molecular parameters of gases in water only.

摘要： 本工作将胡英、徐英年、Prausnitz建立的气体溶解度的分子热力学模型推广到溶剂为电解质溶液的系统中.为计入离子电荷对流体混合物Helmholtz自由能的影响,作者考虑了位于中性分子的第一配位圈中离子的电荷与此分子的诱导偶极和偶极的相互作用.对于第一配位圈以外的离子的影响则由于正、负电荷关于中心分子的对称分布而略去.本模型给出了有效离子硬球直径与Pauling晶格直径的关联式σ=ησ~(cryatal)、其中,η=-6.645+747.2511/T+2.9539×10~(-2)T-5.05798×10~(-5)T~2+3.2431×10~(-8)T~3,T>453.15K时η=1.021.对78个1-1价电解质系统的计算结果表明,本模型只需要气体在水中的分子参数即可在很大的温度和电解质浓度范围内(273K