Ionic liquids have been proposed as green and powerful solvents. Recently ionic liquids have been applied for the removing of sulfur and nitrogen compounds from fuels [1,2]. One of the issues to solve is the regeneration of the ionic liquid after the extraction process. CO2 has been proposed for such regeneration [1,3] because of the very low solubility of the ionic liquids in supercritical CO2; therefore it can be selective for the sulfur compounds [4]. Basic information about phase equilibria and volumetric behavior data are scarce for mixtures involving ionic liquids, sulfur compounds, fuel compounds and CO2 for the understanding of all the phenomena involved in the mentioned separations. In this work, compressed liquid densities were measured for the binary mixtures composed by 1-ethyl-3-methylimidazolium [Emim] chloride + octane and for ternary mixtures composed by [Emim] chloride + octane + CO2 at temperatures from 313 to 363 K and pressures up to 25 MPa. Experimental densities were correlated using two empirical equations [5,6].

Keywords: Density; Ionic liquids, Octane, CO2;

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[5] A. Zúñiga-Moreno, L. A. Galicia-Luna, and L. E. Camacho-Camacho “Compressed Liquid Densities and Excess Volumes of CO2 + Decane Mixtures from (313 to 363) K and Pressures up to 25 MPa.” J. Chem. Eng. Data 2005, 50, 1030-1037.

[6] A. Zúñiga-Moreno, L. A. Galicia-Luna, F. F. Betancourt-Cárdenas. “Compressed Liquid Densities and Excess Volumes of CO2 + Thiophene Binary Mixtures from 313 to 363 K and Pressures up to 25 MPa.” Accepted at Fluid Phase Equilib. 2005.