Thermophysical properties of alkyl acetates in aqueous solutions of ionic liquid {1-butyl-3-methylimidazolium bromide [bmim][Br]} at different temperatures

Abstract

The interactions of alkyl esters with the ionic liquid 1-butyl-3-methylimidazolium bromide [bmim][Br] as a function of temperature have been investigated. The density, ρ, and speed of sound, , of alkyl acetates in aqueous 1-butyl-3-methylimidazolium bromide solutions have been measured in the temperature interval T = (288.15, 293.15, 298.15, 303.15 and 308.15) K and atmospheric pressure. The apparent molar volume () and adiabatic compressibility () of alkyl acetates in aqueous ionic liquid solution were determined at the measured temperatures. The partial molar volume and partial molar adiabatic compressibility of esters at infinite dilution have been calculated. Transfer volumes and transfer adiabatic compressibility () at infinite dilution from water to aqueous ionic liquid solution were also calculated and the temperature dependence on the apparent molar volume was used to calculate apparent molar expansivity and the Hepler’s constant values, . The results have been discussed in terms of intermolecular interactions.