Eur. Phys. J. E (2017) 40: 36
https://doi.org/10.1140/epje/i2017-11520-x

Regular Article

Soret coefficient of the n-dodecane-n-hexane binary mixture under high pressure

¹ MGEP Mondragon Goi Eskola Politeknikoa, Mechanical and Industrial Manufacturing Department, Loramendi 4, Apartado 23, 20500, Mondragon, Spain
² Univ. Pau & Pays Adour, CNRS, TOTAL, LFCR-IPRA, UMR5150, 1 allée du Parc Montaury, 64600, Anglet, France
³ CNES Centre National d’Études Spatiales, 2 place Maurice Quentin, 75 039, Paris Cedex 01, France

^* e-mail: mbouali@mondragon.edu

Received: 30 September 2016
Accepted: 27 February 2017
Published online: 31 March 2017

Abstract

In the present work, the Soret coefficient has been determined at high pressure for a binary hydrocarbon mixture by combining the thermogravitational column and the dynamic near-field imaging techniques. The analyzed mixture is an iso-massic n -dodecane-n -hexane mixture at 298.15K. The molecular diffusion coefficient has been measured up to 20MPa by means of the dynamic analysis of the light scattered by non-equilibrium concentration fluctuations. With a cylindrical thermogravitational column the thermodiffusion coefficient was determined from 0.1MPa to 10MPa. Density, as well as, mass expansion and thermal expansion have been measured with a high pressure densimeter. Dynamic viscosity at up to 20MPa has been determined with a high pressure viscometer. This work shows the decreasing tendency of both the molecular diffusion and the thermodiffusion coefficient with increasing pressure.