Ground based measurement and theoretical calculation of Soret coefficient of binary hydrocarbon mixtures

Measurement of diffusion coefficients is very important for simulation and prediction of oil reservoirs. Recently, a new experimental set up has been built-up in Ryerson University to measure the transport coefficient of transparent liquid mixtures. Laser based optical digital interferometry technique using Mach-Zehnder Interferometer has been used for measuring the diffusion coefficients. This method is non-intrusive, highly accurate and can provide a details 2-D visualization of temperature and concentration field. We have selected five binary liquid mixtures of Decane (C10H22)-Isobutylbenzene (IBB), Decane (C10H22)-1,2,3,4 Tetrahydronaphthalene (THN), Dodecane (C12H26)-Isobutylbenzene (IBB), Dodecane (C12H26)-1,2,3,4 Tetrahydronaphthalene (THN) and Isobutylbenzene (IBB)-1,2,3,4 Tetrahydronaphtha-lene (THN). The mixtures have been prepared from pure C10H22, C12H26, IBB and THN for 50% mass fractions. These five binary mixtures are the representative of binary interactions between alkane, one-ring aromatic and two-ring aromatic hydrocarbons. The thermal design of the diffusion cell as well as data analyzing method has been improved. Comparison of experimental data has been done with two available theocratical expressions such as Firoozabadi et al., and Eslamian and Saghir; both of these expressions are linked with Peng-Robinson equation of state (PR-EOS). Experimental results showed maximum deviation of less than 1% for IBB-C12H26, 2% for THN-IBB and 9% for THN-C12H26 from the available benchmark results.