Strong gas-mineral interactions or slow adsorption kinetics require a molecular-level understanding of both adsorption and diffusion for these interactions to be properly described in transport models. In this combined molecular simulation and experimental study, noble gas adsorption and mobility is investigated in two naturally abundant zeolites whose pores are similar in size (clinoptilolite) and greater than (mordenite) the gas diameters. Simulated adsorption isotherms obtained from grand canonical Monte Carlo simulations indicate that both zeolites can accommodate even the largest gas (Rn). However, gas mobility in clinoptilolite is significantly hindered at pore-limiting window sites, as seen from molecular dynamics simulations in both bulk and slab zeolite models. Experimental gas adsorption isotherms for clinoptilolite confirm the presence of a kinetic barrier to Xe uptake, resulting in the unusual property of reverse Kr/Xe selectivity. Finally, a kinetic model is used to fit the simulated gas loading profiles, allowing a comparison of trends in gas diffusivity in the zeolite pores.

强烈的气体-矿物相互作用或缓慢的吸附动力学需要在分子水平上理解吸附和扩散，以便在传输模型中正确描述这些相互作用。在这项结合了分子模拟和实验研究的研究中，研究了两种天然丰富的沸石的惰性气体吸附和流动性，这两种沸石的孔径相似（斜发沸石），但大于气体直径（丝光沸石）。从大规范蒙特卡罗模拟获得的模拟吸附等温线表明，两种沸石甚至可以容纳最大的气体 (Rn)。然而，从块状和板状沸石模型中的分子动力学模拟可以看出，斜发沸石中的气体流动性在孔隙限制窗口位置受到显着阻碍。斜发沸石的实验气体吸附等温线证实了 Xe 吸收的动力学障碍的存在，导致反向 Kr/Xe 选择性的不寻常特性。最后，使用动力学模型来拟合模拟的气体负载曲线，从而可以比较沸石孔隙中气体扩散率的趋势。