Easily tunable parameterization of a force field for gas adsorption on FAU zeolites

Considering the great economic and environmental interests in the capture and separation of CO2 and the wide availability of faujasites zeolites (FAU), we propose a set of parameters based on classical force fields that has good transferability among Na-FAU sieves and CO2. In addition to CO2, the parameterization strategy was tested for H2S, O-2, N-2 and CH4 gases. For these gases, the force field adequately predicts the adsorption isotherms at low pressure. The force field was also tested for N-2 in the FAU framework with different monovalent and divalent cations, resulting in quantitative agreement for monovalent cations and qualitative agreement for divalent cations. The good tradeoff between the reliability and ease of implementation will enable rapid evaluation of the adsorption properties of gaseous mixtures of industrial relevance. The reasoning of the re-parameterization strategy is also discussed in detail.