Ab Initio Prediction of Adsorption Isotherms for Gas Mixtures by Grand Canonical Monte Carlo Simulations on a Lattice of Sites.
Ab Initio Prediction of Adsorption Isotherms for Gas Mixtures by Grand Canonical Monte Carlo Simulations on a Lattice of Sites.
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DOI：
10.1021/acs.jpclett.7b01205
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发表时间：
2017-06
期刊：
影响因子：
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通讯作者：
Arpan Kundu;Kaido Sillar;J. Sauer
中科院分区：
文献类型：
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作者：
Arpan Kundu;Kaido Sillar;J. Sauer
利用量子化学从头算方法和分子统计学方法获得了各位点上吸附的吉布斯自由能和横向（吸附-吸附）相互作用能。他们定义了一个大规范蒙特卡罗（GCMC）哈密顿量来模拟吸附点阵上的气体混合物。以金属有机骨架CPO-27-Mg （Mg-MOF-74）为例，研究了CO2和CH4在孔隙中Mg2+位点的共吸附。在广泛使用的共吸附模型（如理想吸附溶液理论（IAST））中进行的不同近似模拟表明，它们在描述二元混合物的吸附选择性方面存在局限性。
Gibbs free energies of adsorption on individual sites and the lateral (adsorbate-adsorbate) interaction energies are obtained from quantum chemical ab initio methods and molecular statistics. They define a Grand Canonical Monte Carlo (GCMC) Hamiltonian for simulations of gas mixtures on a lattice of adsorption sites. Coadsorption of CO2 and CH4 at Mg2+ sites in the pores of the metal-organic framework CPO-27-Mg (Mg-MOF-74) is studied as an example. Simulations with different approximations as made in widely used coadsorption models such as the ideal adsorbed solution theory (IAST) show their limitations in describing adsorption selectivities for binary mixtures.