Separation of Carbon Dioxide from Nitrogen and Water in Flue Gas Streams
Grand Canonical Monte Carlo simulations (GCMC) are used to examine the adsorption isotherms of carbon dioxide, nitrogen, and water in metal-organic frameworks (MOFs). Molecular Dynamics (MD) simulations are used to determine the diffusion coefficients of carbon dioxide, nitrogen, and water in MOFs. The metal-organic frameworks studied are copper trimesate (Cu-BTC), zinc terephthalate (IRMOF1), and MIL-47, which belongs to the Materials of the Institute Lavoisier series. Diffusion coefficients are determined by the mean-square displacement method derived by Albert Einstein. The diffusion coefficients of each component in the flue gas are analyzed to examine the effect of temperature in diffusion coefficients and study the motion of the gases in the MOF. At thermal equilibrium, the radial distribution function of carbon dioxide, nitrogen, and water are obtained to find the position of atoms with respect to the metal sites of the MOFs. The selectivity for carbon dioxide in a gas mixture composed of carbon dioxide, nitrogen, and water is determined at room temperature. The selectivity for carbon dioxide in flue gas is found by considering the amount adsorbed of carbon dioxide with respect to the amount adsorbed of nitrogen and the molar fractions of carbon dioxide and nitrogen in the flue gas. To account for the molecular interactions between the molecules in the flue gas and the metal-organic frameworks, van der Waals forces are accounted in this study. The Lennard Jones potential parameters for each atom in the metal-organic framework are obtained from the Dreiding force field. Location of carbon dioxide, nitrogen, and water relative to the metal atom in the MOF is observed using Material Studio 5.5 and Visual Molecular Dynamics. Based on the computational results, MIL-47 has the highest selectivity for carbon dioxide in gas mixture at room temperature because carbon dioxide strongly interacts with vanadium metal. Cu-BTC also shows high selectivity for carbon dioxide, whereas IRMOF-1 has lower selectivity for carbon dioxide.
Subjectmetal-organic frameworks, selectivity of carbon dioxide
flue gas streams
Mera, Hilda 1989- (2012). Separation of Carbon Dioxide from Nitrogen and Water in Flue Gas Streams. Honors and Undergraduate Research. Available electronically from