Thermodynamics Research Center / ThermoML | Thermochimica Acta

ABSTRACT

The interactions of two alkyl acetoacetates ( methyl acetoacetate, and ethyl acetoacetate) in aqueous solutions of an ionic liquid, 1-butyl-3-methylimidazolium bromide [bmim][Br] as a function of temperature have been investigated by combination of volumetric and acoustic methods. The density, and speed of sound, of methyl acetoacetate, ethyl acetoacetate in aqueous 1-butyl-3-methyllimidazolium bronmide solutions have been measured in the temperature interval T = (288.15, 293.15, 298.15, 303.15, and 308.15) K and atmospheric pressure. These data have been used to calculate apparent molar volumes ( ), and apparent molar adiabatic compressibility ( ) of these mixtures at all the five temperatures. The standard partial molar volumes ( ), standard partial molar volumes of transfer ( ), standard partial molar adiabatic compressibility ( ), and standard partial molar adiabatic compressibility ( ) of transfer have been determined for these alkyl acetoacetate solutions from these density and speed of sound data. The resulting values of , , , and for transfer of alkyl acetoacetates from water to aqueous ionic liquid solutions have been interpreted in terms of solute + solvent interactions. Later, the temperature dependence of the apparent molar volume was used to calculate apparent molar expansivity and the Hepler's constant values, to confirm the conclusions obtained from volumetric and speed of sound properties.