Artigo de Periódico
Thermophysical properties of binary mixtures of {ionic liquid 2-hydroxy ethylammonium acetate + (water, methanol, or ethanol)}
Fecha
2011Registro en:
0021-9614
v. 43, n. 7.
Autor
Alvarez, Víctor H.
Silva, Silvana Mattedi e
Martin-Pastor, Manuel
Aznar, Martin
Duro, Miguel Angel Iglesias
Alvarez, Víctor H.
Silva, Silvana Mattedi e
Martin-Pastor, Manuel
Aznar, Martin
Duro, Miguel Angel Iglesias
Institución
Resumen
In this work, density and speed of sound data of binary mixtures of an ionic liquid consisting of {2-
hydroxy ethylammonium acetate (2-HEAA) + (water, methanol, or ethanol)} have been measured
throughout the entire concentration range, from the temperature of (288.15 to 323.15) K at atmospheric
pressure. The excess molar volumes, variations of the isentropic compressibility, the apparent molar volume,
isentropic apparent molar compressibility, and thermal expansion coefficient were calculated from
the experimental data. The excess molar volumes were negative throughout the whole composition
range. Compressibility data in combination with low angle X-ray scattering and NMR measurements
proved that the presence of micelles formed due to ion pair interaction above a critical concentration
of the ionic liquid in the mixtures. The Peng–Robinson equation of state coupled with the Wong–Sandler
mixing rule and COSMO–SAC model was used to predict densities and the calculated deviations were
lower than 3%, for binary mixtures in all composition range.