Steady-state Measurements of Ternary Mixtures in Thermogravitational Microcolumn Using Optical Digital Interferometry

Identifier:  imarina:9162271

Handle: https://hdl.handle.net/20.500.11797/imarina9162271

Authors:  Šeta B; Lapeira E; Gavalda J; Bou-Ali MM; Ruiz X

Abstract:
© 2021, The Author(s), under exclusive licence to Springer Nature B.V. part of Springer Nature. Steady-state measurements in a thermogravitational microcolumn using optical digital interferometry are presented here for the first time in the literature in the case of ternary mixtures. These measurements enabled the subsequent obtaining of thermodiffusion coefficients of a ternary mixture once convection reaches the steady-state. The ternary mixture used was the benchmark one, tetrahydronaphthalene (THN) – isobutylbenzene (IBB) and n-dodecane (nC12) with mass fraction of 0.8-0.1-0.1 respectively. Contrast factors due to the change in the concentration field were measured and compared with the corresponding ones in the literature. Uncertainty in the results was found to be of similar order of magnitude as in the case of Selectable Optical Diagnostic Instrument (SODI), which means that the condition number of that contrast factor matrix is almost equal to the present one. Final values of thermodiffusion coefficients were compared with the results reported from other optical techniques, as well as with the results obtained by the traditional long opaque thermogravitational columns (TGC). Some proposals were then made in order to improve accuracy reducing the condition number of the contrast factor matrix.