Vapor Pressures of the 1-Butyl-3-methylimidazolium Bromide + Water, 1-Butyl-3-methylimidazolium Tetrafluoroborate + Water, and 1-(2-Hydroxyethyl)-3-methylimidazolium Tetrafluoroborate + Water Systems

Abstract

This work presents the vapor pressures of the following binary imidazolium-based ionic liquid (IL) + water solutions: 1-butyl-3-methylimidazolium bromide ([bmim][Br]) + water, 1-butyl-3-methylimidazolium tetrafluoroborate ([bmim][BF4]) + water, and 1-(2-hydroxyethyl)-3-methylimidazolium tetrafluoroborate ([hydemim][BF4]) + water. Vapor pressures were measured by using the boiling-point method in the temperature range of (304.8 to 475.2) K and in the concentration range of (20.0 to 80.0) mol % of ILs and were correlated with an Antoine-type equation. The resulting average absolute deviations (AAD) between the experimental and calculated values were found to be (0.419, 1.16, and 0.682) % for the [bmim][Br] + water, [bmim][BF4] + water, and [hydemim][BF4] + water solutions, respectively.