Klein T, Piszko M, Lang M, Mehler J, Schulz P, Rausch MH, Giraudet C, Koller TM, Fröba AP (2020)
Publication Language: English
Publication Type: Journal article, Original article
Publication year: 2020
Book Volume: 65
Pages Range: 4116–4129
Journal Issue: 8
Ionic liquids (ILs) are interesting working fluids in many areas of chemical and energy engineering such as gas separation, catalysis, or energy storage. For the optimum design of related processes and apparatuses, the diffusion coefficient of gases dissolved in ILs is necessary, yet is often only known for a few selected gases. In this work, the thermal and mutual diffusivities in binary mixtures consisting of the gases hydrogen, helium, nitrogen, carbon monoxide, carbon dioxide, or krypton dissolved in the homologous series of the ILs [EMIM][NTf2], [HxMIM][NTf2], or [DcMIM][NTf2] were investigated by dynamic light scattering (DLS) and equilibrium molecular dynamics (EMD) simulations for temperatures between (298 and 423) K at conditions close to infinite dilution of the dissolved gas. Here, the Fick diffusion coefficient determined by DLS can be compared with the self-diffusion coefficient of the dissolved gases predicted by EMD simulations. For the latter, selected force fields (FFs) for the ILs available in literature were tested, for which the most suitable FF was modified by scaling the partial charges of all atoms with an IL-specific factor using experimental data for density, viscosity, and the self-diffusion coefficient of the pure ILs. On the basis of the modified FF, agreement of the calculated gas self-diffusion coefficients and the experimental Fick diffusion coefficients with an average absolute relative deviation of 12% was found. The Fick diffusion coefficient increases with decreasing molecular weight of the dissolved gas, with the exception of hydrogen and helium, which show an inverse behavior. In contrast to the trends observed for binary mixtures of the above gases dissolved in n-alkanes or 1-alcohols of varying alkyl chain length, the diffusion coefficients of the mixtures with the different ILs investigated in this study were found to be not significantly affected by the solvent viscosity.
APA:
Klein, T., Piszko, M., Lang, M., Mehler, J., Schulz, P., Rausch, M.H.,... Fröba, A.P. (2020). Diffusivities in Binary Mixtures of [AMIM][NTf2] Ionic Liquids with the Dissolved Gases H2, He, N2, CO, CO2, or Kr Close to Infinite Dilution. Journal of Chemical and Engineering Data, 65(8), 4116–4129. https://dx.doi.org/10.1021/acs.jced.0c00430
MLA:
Klein, Tobias, et al. "Diffusivities in Binary Mixtures of [AMIM][NTf2] Ionic Liquids with the Dissolved Gases H2, He, N2, CO, CO2, or Kr Close to Infinite Dilution." Journal of Chemical and Engineering Data 65.8 (2020): 4116–4129.
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