Issue 18, 2004

The liquid–liquid coexistence of binary mixtures of the room temperature ionic liquid1-methyl-3-hexylimidazolium tetrafluoroborate with alcohols

Abstract

Precise coexistence curves are reported for the liquid–liquid phase transition of binary solutions of the room temperature ionic liquid (RTIL) 1-methyl-3-hexylimidazolium tetrafluoroborate (C6mim+BF4) in a series of alcohols (1-butanol, 1-pentanol, 2-butanol, and 2-pentanol). The phase diagrams are determined by measuring the temperature dependence of the refractive index in the two phases of samples of critical composition. The critical data of the systems are in the region predicted for the model fluid of equal-sized, charged, hard spheres in a dielectric continuum, the so-called restricted primitive model (RPM). Therefore, the phase transition can be classified as essentially driven by Coulomb interactions. The effective exponents βeff determined are close to the universal Ising value, where the deviations are found to be negative, when the volume fraction or the mass fraction are chosen as concentration variable. The negative values of the first Wegner correction indicate non-uniform crossover from Ising to mean-field criticality. The diameter of the coexistence curves shows the non-analytic temperature dependence typical for Ising systems.

Article information

Article type
Paper
Submitted
20 Apr 2004
Accepted
08 Jul 2004
First published
26 Jul 2004

Phys. Chem. Chem. Phys., 2004,6, 4421-4431

The liquid–liquid coexistence of binary mixtures of the room temperature ionic liquid 1-methyl-3-hexylimidazolium tetrafluoroborate with alcohols

M. Wagner, O. Stanga and W. Schröer, Phys. Chem. Chem. Phys., 2004, 6, 4421 DOI: 10.1039/B404933K

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements