Thermodynamics Research Center / ThermoML | Journal of Chemical Thermodynamics

ABSTRACT

The interactions of alkoxyalkanols with the ionic liquid 1-butyl-3-methylimidazolium bromide [bmim][Br] as a function of temperature were investigated by combination of volumetric and acoustic methods. The density, q, and speed of sound, u, of ethylene glycol monomethyl ether, diethylene glycol monomethyl ether, and triethylene glycol monomethyl ether (0.00 1.01 mol kg 1) in aqueous 1-butyl-3- methylimidazolium bromide solutions ranging from pure water to 0.29 mass% of ionic liquid have been measured at T = (288.15, 298.15 and 308.15) K and atmospheric pressure. The apparent molar volume (V/) and adiabatic compressibility (K/,S) of alkoxyalkanols in aqueous ionic liquid solution were determined at the measured temperatures. The partial molar volume oV0 /P and partial molar adiabatic compressibility oK0 uP of alkoxyalkanols at infinite dilution were evaluated. Transfer volumes oDV0 /P and transfer adiabatic compressibility (DK0 /) at infinite dilution from water to aqueous ionic liquid solution were also calculated. The temperature dependence of the apparent molar volume was used to calculate apparent molar expansivity (/0E ) and the Hepler s constant values, o@2V0 /=@T2P. The results were explained on the basis of competing patterns of interactions of co-solvent and the solute.