ABSTRACT

The speed of sound in the ionic liquid (IL) N-methyl-2-hydroxyethylammonium propionate (m2HEAPr) was measured at atmospheric pressure, and over the range of temperatures T = (293.15 to 343.15) K. The speed of sound and density were also measured for aqueous mixtures of the ionic liquid throughout the entire concentration range at temperatures T = (298.15 to 333.15) K and atmospheric pressure. The excess molar volume, excess isentropic compressibility, excess speed of sound, apparent molar volume, and isentropic apparent molar compressibility were calculated from the values of the experimental density and speed of sound. The results were analyzed and are discussed from the point of view of structural changes in the aqueous medium. All the above mentioned properties were correlated with selected analytical functions. The Jouyban Acree model was used to correlate the density of the mixtures studied with the temperature. The model accuracy was evaluated by calculating the absolute average deviation (AAD) for the correlation, which is 0.4%. The speed of sound of the m2HEAPr was predicted with the Wu et al. model with a maximum deviation of 2%. The molar compressibility of m2HEAPr and their aqueous mixtures was calculated from the Wada s model. To the authors knowledge, this is the first time this model is applied to these systems. The results demonstrate that the molar compressibility calculated from Wada s model is almost a linear function of mole fraction and can be considered as temperature independent for a fixed mole fraction over the whole composition range.

Compounds

#	Formula	Name
1	H2O	water
2	C6H15NO3	2-hydroxy-N-methylethanaminium propionate

Datasets

The table above is generated from the ThermoML associated json file (link above). POMD and RXND refer to PureOrMixture and Reaction Datasets. The compound numbers are included in properties, variables, and phases, if specificied; the numbers refer to the table of compounds on the left.
Type	Compound-#	Property	Variable	Constraint	Phase	Method	#Points
POMD	2	Speed of sound, m/s ; Liquid	Temperature, K; Liquid	Pressure, kPa; Liquid Frequency, MHz; Liquid	Liquid	Single path-length method	11
POMD	1 2	Mass density, kg/m3 ; Liquid	Temperature, K; Liquid Mole fraction - 2; Liquid	Pressure, kPa; Liquid	Liquid	Vibrating tube method	96
POMD	1 2	Speed of sound, m/s ; Liquid	Temperature, K; Liquid Mole fraction - 2; Liquid	Pressure, kPa; Liquid Frequency, MHz; Liquid	Liquid	Single path-length method	96

Thermodynamics Research Center / ThermoML | Journal of Chemical Thermodynamics

Volumetric and acoustical properties of aqueous mixtures of N-methyl-2-hydroxyethylammonium propionate at T = (298.15 to 333.15) K

Li, Y.[Yang], Figueiredo, E. J. P.[Eduardo J. P.], Santos, M. J. S. F.[Mario J.S.F.], Santos, J. B.[Jaime B.], Talavera-Prieto, N. M. C.[Nieves M. C.], Carvalho, P. J.[Pedro J.], Ferreira, A. G. M.[Abel G. M.], Mattedi, S.[Silvana]

ABSTRACT