Diffusivities of Ternary Mixtures of n-Alkanes with Dissolved Gases by Dynamic Light Scattering

Journal article
(Original article)


Publication Details

Author(s): Heller A, Giraudet C, Makrodimitri ZA, Fleys MSH, Chen J, van der Laan GP, Economou IG, Rausch MH, Fröba AP
Journal: Journal of Physical Chemistry B
Publisher: AMER CHEMICAL SOC
Publication year: 2016
Volume: 120
Journal issue: 41
Pages range: 10808-10823
ISSN: 1520-6106
eISSN: 1520-5207
Language: English


Abstract


Theoretical approaches suggest that dynamic light scattering (DLS) signals from low-molecular-weight ternary mixtures are governed by fluctuations in temperature as well as two individual contributions from fluctuations in concentration that are related to the eigenvalues of the Fick diffusion matrix. Until now, this could not be proven experimentally in a conclusive way. In the present study, a detailed analysis of DLS signals in ternary mixtures consisting of n-dodecane (n-C12H26) and n-octacosane (n-C28H58) with dissolved hydrogen (H-2), carbon monoxide (CO), or water (H2O) as well as of n-C12H26 or n-C28H58 with dissolved H-2 and CO is given for temperatures up to 523 K and pressures up to 4.1 MPa. Thermal diffusivities of pure n-C12H26 and n-C28H58 as well as thermal and mutual diffusivities of their binary mixtures being the basis for the ternary mixtures with dissolved gas were studied for comparison purposes. For the investigated ternary mixtures, three individual signals could be distinguished in the time-resolved analysis of scattered light intensity by using photon correlation spectroscopy (PCS). For the first time, it could be evidenced that these signals are clearly associated with hydrodynamic modes. In most cases, the fastest mode observable for ternary mixtures is associated with the thermal diffusivity. The two further modes obviously related to the molecular mass transport are observable on different time scales and comparable to the modes associated with the concentration fluctuations in the respective binary mixtures. Comparison of the experimental data with results from molecular dynamics simulations revealed very good agreement.



FAU Authors / FAU Editors

Fröba, Andreas Paul Prof. Dr.-Ing.
Lehrstuhl für Advanced Optical Technologies - Thermophysical Properties
Giraudet, Cédric Dr.
Erlangen Graduate School in Advanced Optical Technologies
Heller, Andreas
Lehrstuhl für Advanced Optical Technologies - Thermophysical Properties
Rausch, Michael Heinrich Dr.-Ing.
Lehrstuhl für Advanced Optical Technologies - Thermophysical Properties


External institutions with authors

National Centre for Scientific Research (NCSR) "Demokritos"


How to cite

APA:
Heller, A., Giraudet, C., Makrodimitri, Z.A., Fleys, M.S.H., Chen, J., van der Laan, G.P.,... Fröba, A.P. (2016). Diffusivities of Ternary Mixtures of n-Alkanes with Dissolved Gases by Dynamic Light Scattering. Journal of Physical Chemistry B, 120(41), 10808-10823. https://dx.doi.org/10.1021/acs.jpcb.6b08117

MLA:
Heller, Andreas, et al. "Diffusivities of Ternary Mixtures of n-Alkanes with Dissolved Gases by Dynamic Light Scattering." Journal of Physical Chemistry B 120.41 (2016): 10808-10823.

BibTeX: 

Last updated on 2018-10-08 at 18:23