IFP Energies Nouvelles, Direction Catalyse et Séparation, Rond-point de l'échangeur de Solaize, 69360 Solaize, France.
Dalton Trans. 2012 Apr 14;41(14):4052-9. doi: 10.1039/c2dt12102f. Epub 2012 Feb 22.
Carbon dioxide is the main undesirable compound present in raw natural gas and biogas. Physisorption based adsorption processes such as pressure swing adsorption (PSA) are one of the solutions to selectively adsorb CO(2) from CH(4). Some hybrid crystalline porous materials that belong to the family of metal-organic frameworks (MOFs) show larger CO(2) adsorption capacity compared to the usual industrial adsorbents, such as zeolites and most activated carbons, which makes them potentially promising for such applications. However, their selectivity values have been most often determined using only single gas adsorption measurements combined with simple macroscopic thermodynamic models or by means of molecular simulations based on generic forcefields. The transfer of this systematic approach to all MOFs, whatever their complex physico-chemical features, needs to be considered with caution. In contrast, direct co-adsorption measurements collected on these new materials are still scarce. The aim of this study is to perform a complete analysis of the CO(2)-CH(4) co-adsorption in the mesoporous MIL-100(Cr) MOF (MIL stands for Materials from Institut Lavoisier) by means of a synergic combination of outstanding experimental and modelling tools. This solid has been chosen both for its fundamental interests, given its very large CO(2) adsorption capacities and its complexity with a combination of micropores and mesopores and the existence of unsaturated accessible metal sites. The predictions obtained by means of Grand Canonical Monte Carlo simulations based on generic forcefields as well as macroscopic thermodynamic (IAST, RAST) models will be compared to direct the co-adsorption experimental data (breakthrough curve and volumetric measurements).
二氧化碳是存在于原始天然气和沼气中的主要不良化合物。基于物理吸附的吸附工艺，如变压吸附（PSA），是从 CH4 中选择性吸附 CO2 的解决方案之一。一些属于金属有机骨架（MOF）家族的混合结晶多孔材料与通常的工业吸附剂（如沸石和大多数活性炭）相比，表现出更大的 CO2 吸附能力，这使得它们在这些应用中具有潜在的应用前景。然而，它们的选择性值通常是通过仅使用单一气体吸附测量值结合简单的宏观热力学模型或基于通用力场的分子模拟来确定的。将这种系统方法转移到所有 MOF 上，无论其复杂的物理化学特征如何，都需要谨慎考虑。相比之下，这些新材料的直接共吸附测量仍然很少。本研究的目的是通过协同组合出色的实验和建模工具，对介孔 MIL-100(Cr) MOF（MIL 代表 Institut Lavoisier 的材料）中的 CO2-CH4 共吸附进行全面分析。选择这种固体，既是因为其具有很大的 CO2 吸附能力，其结构复杂，具有微孔和介孔的组合以及不饱和可及金属位，也因为其具有很大的 CO2 吸附能力，其结构复杂，具有微孔和介孔的组合以及不饱和可及金属位。基于通用力场的 Grand Canonical Monte Carlo 模拟的预测结果以及宏观热力学（IAST、RAST）模型将与直接共吸附实验数据（穿透曲线和体积测量）进行比较。
