Mutual and Thermal Diffusivities in Mixtures of Cyclohexane, n-Hexadecane, n-Octacosane, or n-Hexanoic Acid with Carbon Dioxide Obtained by Dynamic Light Scattering and Molecular Dynamics Simulations

Piszko M, Lenahan F, Friedl L, Klein T, Fröba AP (2022)

Publication Language: English

Publication Type: Journal article, Original article

Publication year: 2022

Journal

Journal of Chemical and Engineering Data American Chemical Society

Book Volume: 67

Pages Range: 3059-3076

Journal Issue: 10

DOI: 10.1021/acs.jced.2c00487

Abstract

The present work reports Fick diffusion coefficients D11 in the saturated liquid phases of binary mixtures of cyclohexane, n-hexadecane, noctacosane, or n-hexanoic acid and dissolved carbon dioxide (CO2) as a function of composition. D11 is experimentally determined by dynamic light scattering (DLS) and predicted by equilibrium molecular dynamics (EMD) simulations within or close to saturation conditions at temperatures between 303 and 423 K and CO2 mole fractions xCO2 up to 0.99. Thermal diffusivity data obtained simultaneously by DLS are reported as well. The mixture composition of the liquid phases is experimentally determined by polarization-difference Raman spectroscopy (PDRS). The combination of PDRS experiments and EMD simulations, where the latter allows a direct insight into or the detection of changes of the fluid structure, is used to investigate the influence of the phase behavior and the resulting fluid structure on D11. The behavior of the experimentally determined D11 and that obtained from EMD simulations by the independent calculation of the Maxwell-Stefan diffusivity and the thermodynamic factor show generally good agreement. Distinct structural changes are reflected by the thermodynamic factors, which are between about 0.35 and 1.4. D11 as a function of xCO2 at a given temperature is nearly constant in mixtures of n-hexanoic acid and CO2 due to the opposing kinetic and thermodynamic contributions to D11. Pronounced composition-dependent behaviors are observed in the other mixtures due to the proximity to a liquid-liquid miscibility gap or the mixtures' critical line.

Authors with CRIS profile

Maximilian Piszko Institute of Advanced Optical Technologies - Thermophysical Properties (AOT-TP) Frances Lenahan Institute of Advanced Optical Technologies - Thermophysical Properties (AOT-TP) Tobias Klein Institute of Advanced Optical Technologies - Thermophysical Properties (AOT-TP) Andreas Paul Fröba Institute of Advanced Optical Technologies - Thermophysical Properties (AOT-TP)

Additional Organisation(s)

Erlangen Graduate School in Advanced Optical Technologies

Related research project(s)

Characterization of molecular diffusion in liquids with dissolved gases July 1, 2019 - June 30, 2023

How to cite

APA:

Piszko, M., Lenahan, F., Friedl, L., Klein, T., & Fröba, A.P. (2022). Mutual and Thermal Diffusivities in Mixtures of Cyclohexane, n-Hexadecane, n-Octacosane, or n-Hexanoic Acid with Carbon Dioxide Obtained by Dynamic Light Scattering and Molecular Dynamics Simulations. Journal of Chemical and Engineering Data, 67(10), 3059-3076. https://dx.doi.org/10.1021/acs.jced.2c00487

MLA:

Piszko, Maximilian, et al. "Mutual and Thermal Diffusivities in Mixtures of Cyclohexane, n-Hexadecane, n-Octacosane, or n-Hexanoic Acid with Carbon Dioxide Obtained by Dynamic Light Scattering and Molecular Dynamics Simulations." Journal of Chemical and Engineering Data 67.10 (2022): 3059-3076.

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