Skip to content
Licensed Unlicensed Requires Authentication Published by De Gruyter June 24, 2020

A Theoretical Study of the Temperature Gradient Effect on the Soret Coefficient in n-Pentane/n-Decane Mixtures Using Non-Equilibrium Molecular Dynamics

  • Xiaoyu Chen , Ruquan Liang EMAIL logo , Yong Wang , Ziqi Xia , Lichun Wu , Yang Liang and Gan Cui

Abstract

The effect of the temperature gradient on the Soret coefficient in n-pentane/n-decane (n-C5/n-C10) mixtures was investigated using non-equilibrium molecular dynamics (NEMD) with the heat exchange (eHEX) algorithm. n-Pentane/n-decane mixtures with three different compositions (0.25, 0.5, and 0.75 mole fractions, respectively) and the TraPPE-UA force field were used in computing the Soret coefficient (ST) at 300 K and 1 atm. Added/removed heat quantities (ΔQ) of 0.002, 0.004, 0.006, 0.008, and 0.01 kcal/mol were employed in eHEX processes in order to study the effect of different thermal gradients on the Soret coefficient. Moreover, a phenomenological description was applied to discuss the mechanism of this effect. Present results show that the Soret coefficient values firstly fluctuate violently and then become increasingly stable with increasing ΔQ (especially in the mixture with a mole fraction of 0.75), which means that ΔQ has a smaller effect on the Soret coefficient when the temperature gradient is higher than a certain thermal gradient. Thus, a high temperature gradient is recommended for calculating the Soret coefficient under the conditions that a linear response and constant phase are ensured in the system. In addition, the simulated Soret coefficient obtained at the highest ΔQ within three different compositions is in great agreement with experimental data.

Award Identifier / Grant number: 51676031

Award Identifier / Grant number: 51976087

Funding statement: The present work was supported financially by the National Natural Science Foundation of China (grant numbers 51676031 and 51976087).

References

[1] C. Ludwig, Diffusion zwischen ungleich erwarten orten gleich zusammengestzter losungen, Sitzungsber. Math.-Naturwiss. Cl. Kaiserlichen Akad. Wiss.20 (1856), 539.Search in Google Scholar

[2] C. Soret, Sur l’état d’équilibre que prend au point de vue de sa concentration une dissolution saline primitivement homohéne dont deux parties sont portées à des températures différentes, Arch. Sci. Phys. Nat.2 (1979), 48–61.Search in Google Scholar

[3] M. Eslamian and M. Z. Saghir, Modeling of DNA thermophoresis in dilute solutions using the non-equilibrium thermodynamics approach, J. Non-Equilib. Thermodyn.37 (2012), 63–76.10.1515/jnetdy.2011.026Search in Google Scholar

[4] M. Siemer, T. Marquardt, G. V. Huerta and S. Kabelac, Local entropy production rates in a polymer electrolyte membrane fuel cell, J. Non-Equilib. Thermodyn.42 (2017), 1–30.10.1515/jnet-2016-0025Search in Google Scholar

[5] V. Bustos and M. Mayorga, Non-equilibrium thermodynamics of magnetic colloids with tunable dipolar interactions, J. Non-Equilib. Thermodyn.35 (2010), 35–50.10.1515/jnetdy.2010.003Search in Google Scholar

[6] A. Palumbo, A. Valenti and G. Lebon, Thermodynamics of suspensions of polymeric chains in dilute solutions, J. Non-Equilib. Thermodyn.35 (2010), 181–194.10.1515/jnetdy.2010.010Search in Google Scholar

[7] L. Hadji, Modeling convection onset in colloidal suspensions of particles, J. Non-Equilib. Thermodyn.36 (2011), 203–227.10.1515/JNETDY.2011.013Search in Google Scholar

[8] K. Binder, Spinodal decomposition in confined geometry, J. Non-Equilib. Thermodyn.23 (1998), 1–44.Search in Google Scholar

[9] P. Burgos-Madrigal, D. F. Mendoza and M. L. D. Haro, On entropy generation and the effect of hear and mass transfer coupling in a distillation process, J. Non-Equilib. Thermodyn.43 (2017), 57–74.10.1515/jnet-2017-0039Search in Google Scholar

[10] V. M. Barragan and S. Kjelstrup, Thermo-osmosis in membrane systems: A review, J. Non-Equilib. Thermodyn.42 (2017), 217–236.10.1515/jnet-2016-0088Search in Google Scholar

[11] E. E. Michaelides, Transport properties of nanofluids: A critical review, J. Non-Equilib. Thermodyn.38 (2013), 1–79.10.1515/jnetdy-2012-0023Search in Google Scholar

[12] J. M. Ortiz-Zarate, F. Garcia-Lopez and J. I. Mengual, The effect of unstirred layers on thermoosmosis, J. Non-Equilib. Thermodyn.14 (1989), 267–278.10.1515/jnet.1989.14.3.267Search in Google Scholar

[13] M. Marcoux and P. Costeseque, Study of transversal dimension influence on species separation in thermogravitational diffusion columns, J. Non-Equilib. Thermodyn.32 (2007), 289–298.10.1515/JNETDY.2007.021Search in Google Scholar

[14] P. Blance, M. M. Bou-Ali, J. K. Platten, J. A. Madariaga, P. Urteaga and C. Santamaria, Thermodiffusion coefficient for binary liquid hydrocarbon mixtures, J. Non-Equilib. Thermodyn.32 (2007), 309–317.10.1515/JNETDY.2007.023Search in Google Scholar

[15] G. Meriguet, G. Demouchy, E. Dubois, R. Perzynski and A. Bourdon, Experimental determination of the Soret coefficient of ionic ferrofluids: influence of the volume fraction and ionic strength, J. Non-Equilib. Thermodyn.32 (2007), 271–279.10.1515/JNETDY.2007.019Search in Google Scholar

[16] A. Abbasi, M. Z. Saghir and M. Kawaji, Theoretical and experimental comparison of the Soret effect for binary mixtures of toluene and n-hexane, and benzene and n-heptane, J. Non-Equilib. Thermodyn.35 (2010), 1–14.10.1515/jnetdy.2010.001Search in Google Scholar

[17] A. Abbasi, M. Z. Saghir and M. Kawaji, An improved thermodiffusion model for ternary mixtures using Fujita’s free volume theory, J. Non-Equilib. Thermodyn.36 (2011), 259–272.10.1515/JNETDY.2011.016Search in Google Scholar

[18] M. Eslamian and M. Z. Saghir, A critical review of thermodiffusion models: role and significance of the heat of transport and the activation energy of viscous flow, J. Non-Equilib. Thermodyn.34 (2009), 97–131.10.1515/JNETDY.2009.007Search in Google Scholar

[19] G. Galliero, M. Bugal, B. Duguay and F. Montel, Mass effect on thermodiffusion using molecular dynamics, J. Non-Equilib. Thermodyn.32 (2007), 251–258.10.1515/JNETDY.2007.017Search in Google Scholar

[20] M. R. Toosi and M. H. Pevrovi, Influence of molecular parameters on the thermodiffusion and thermal conductivity in binary mixtures of diatomic fluids using NEMD, J. Non-Equilib. Thermodyn.34 (2009), 61–74.10.1515/JNETDY.2009.004Search in Google Scholar

[21] M. Zhang and F. Muller-Plathe, Reverse nonequilibrium molecular-dynamics calculation of the Soret coefficient in liquid benzene/cyclohexane mixtures, J. Chem. Phys.123 (2005), 124502.10.1063/1.2042427Search in Google Scholar PubMed

[22] C. Nieto-Draghi, J. B. Avalos and B. Rousseau, Computing the Soret coefficient in aqueous mixtures using boundary driven nonequilibrium molecular dynamics, J. Chem. Phys.122 (2005), 114503.10.1063/1.1863872Search in Google Scholar PubMed

[23] A. Perronace, C. Leppla, F. Leroy, B. Rousseau and S. Wigand, Soret and mass diffusion measurements and molecular dynamics simulations of n-pentane-n-decane mixtures, J. Chem. Phys.116 (2002), 3718–3729.10.1063/1.1436473Search in Google Scholar

[24] S. H. Mozaffari, S. Srinivasan and M. Z. Saghir, Thermodiffusion in binary and ternary hydrocarbon mixtures studied using a modified heat exchange algorithm, Therm. Sci. Eng. Prog.4 (2017), 168–174.10.1016/j.tsep.2017.10.001Search in Google Scholar

[25] S. Antoun, M. Z. Saghir and S. Srinivasan, An improved molecular dynamics algorithm to study thermodiffusion in binary hydrocarbon mixtures, J. Chem. Phys.148 (2018), 104507.10.1615/IHTC16.mpe.024664Search in Google Scholar

[26] F. A. Furtado, A. J. Silveira, C. R. A. Abreu and F. W. Tavares, Non-equilibrium molecular dynamics used to obtain Soret coefficients of binary hydrocarbon mixtures, Braz. J. Chem. Eng.32 (2015), 683–698.10.1590/0104-6632.20150323s00003445Search in Google Scholar

[27] P. Wirnsberger, D. Frenkel and C. Dellago, An enhanced version of the heat exchange algorithm with excellent energy conservation properties, J. Chem. Phys.143 (2015), 124104.10.1063/1.4931597Search in Google Scholar PubMed

[28] Z. A. Makrodimitri, D. J. M. Unruh and I. G. Economou, Molecular simulation of diffusion of hydrogen, carbon monoxide, and water in heavy n-alkanes, J. Phys. Chem. B115 (2011), 1429–1439.10.1021/jp1063269Search in Google Scholar PubMed

[29] T. Ikeshoji and B. Hafskjold, Non-equilibrium molecular dynamics calculation of heat conduction in liquid and through liquid-gas interface, Mol. Phys.81 (1994), 251–261.10.1080/00268979400100171Search in Google Scholar

[30] F. Bresme, B. Hafskjold and I. Wold, Nonequilibrium molecular dynamics study of heat conduction in ionic systems, J. Phys. Chem. B100 (1996), 1879–1888.10.1021/jp9512321Search in Google Scholar

[31] M. G. Martin and J. I. Siepmann, Transferable potentials for phase equilibria. 1. United-atom description of n-Alkanes, J. Phys. Chem. B102 (1998), 2569–2577.10.1021/jp972543+Search in Google Scholar

[32] W. M. Brown, P. Wang, S. J. Plimpton and A. N. Tharrington, Implementing molecular dynamics on hybrid high performance computers – short range forces, Comput. Phys. Commun.182 (2011), 898–911.10.1016/j.cpc.2010.12.021Search in Google Scholar

[33] G. Pranami and M. H. Lamm, Estimating error in diffusion coefficients derived from molecular dynamics simulations, J. Chem. Theory Comput.11 (2015), 4586–4592.10.1021/acs.jctc.5b00574Search in Google Scholar PubMed

[34] S. Kjelstrup, D. Bedeaux, I. Inzoli and J. M. Simon, Criteria for validity of thermodynamic equations from non-equilibrium molecular dynamics simulations, Energy33 (2008), 1185–1196.10.1016/j.energy.2008.04.005Search in Google Scholar

[35] E. Fishman, Self-diffusion in liquid normal pentane and normal heptane, J. Phys. Chem.59 (1955), 469–472.10.1021/j150527a022Search in Google Scholar

[36] M. Gehrig and H. Lentz, Values of p(V,T) for n-pentane in the range 5 to 250 MPa and 313 to 643 K, J. Chem. Thermodyn.11 (1979), 291–300.10.1016/0021-9614(79)90154-XSearch in Google Scholar

[37] J. W. Mutoru, W. Smith, C. S. O’Hern and A. Firoozabadi, Molecular dynamics simulations of diffusion and clustering along critical isotherms of medium-chain n-alkanes, J. Chem. Phys.138 (2013), 563.10.1063/1.4773282Search in Google Scholar PubMed

[38] P. Blanco, P. Polyakov, M. M. Bou-Ali and S. Wiegand, Thermal diffusion and molecular diffusion values for some alkane mixtures: A comparison between thermogravitational column and thermal diffusion forced Rayleigh scattering, J. Phys. Chem. B112 (2008), 8340–8345.10.1021/jp801894bSearch in Google Scholar PubMed

[39] J. W. Moore and R. M. Wellek, Diffusion coefficients of n-heptane and n-decane in n-alkanes and n-alcohols at several temperatures, J. Chem. Eng. Data19 (1974), 136–140.10.1021/je60061a023Search in Google Scholar

[40] J. A. Young, n-Pentane, J. Chem. Educ.86 (2009), 26.10.1021/ed086p26Search in Google Scholar

[41] I. M. Smallwood, n-Decane, Handbook of Organic Solvent Properties11 (1996), 23–25.10.1016/B978-0-08-052378-1.50010-4Search in Google Scholar

[42] G. Galliero, H. Bataller, J. P. Bazile, J. Diaz, F. Croccolo, H. Hoang, et al., Thermodiffusion in multicomponent n-alkane mixtures, NPJ Microgravity3 (2017), 20.10.1038/s41526-017-0026-8Search in Google Scholar PubMed PubMed Central

[43] A. D. M. David, M. M. Bou-Ali, J. A. Madariaga and C. Santaria, Mass effect on the Soret coefficient in n-alkane mixtures, J. Chem. Phys.140 (2014), 084503.10.1063/1.4865936Search in Google Scholar PubMed

[44] M. Chacha, D. Faruque, M. Z. Saghir and J. C. Legros, Solutal thermodiffusion in binary mixture in the presence of g-jitter, Int. J. Therm. Sci.41 (2002), 899–911.10.1016/S1290-0729(02)01382-0Search in Google Scholar

Received: 2019-10-15
Revised: 2020-05-12
Accepted: 2020-06-09
Published Online: 2020-06-24
Published in Print: 2020-10-25

© 2020 Walter de Gruyter GmbH, Berlin/Boston

Downloaded on 25.4.2024 from https://www.degruyter.com/document/doi/10.1515/jnet-2019-0082/html
Scroll to top button