Abstract

Methane and sulfur hexafluoride contribute significantly to the greenhouse effect. The aim of this research is to accomplish a theoretical study of the capture and the storage of these two gases and water in Zeolitic Imidazolate Frameworks (ZIF). Density functional theory (DFT) is employed to understand the behavior of the gases absorbed in ZIF-4 and ZIF-6 cages. The adsorption capacities of the pure gases and gas mixtures in the two different types of ZIFs are compared over a large range of pressures. Negative adsorption energies in ZIF-6 for SF6 and CH4are obtained when they are treated individually and in mixtures with H2O. The result analysis gives a clue to what sites of the ZIFs are the favored for molecular adsorption being close to the imidazole ring, how many molecules may be attached to the surface of the pores, and how such structures look like. Adsorption energies range between −13 eV < Eads < 11 eV. Mechanisms for adsorption and adsorption isotherms are described. The results confirm previous theoretical studies and available experimental data.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.