Thermodynamics Research Center / ThermoML | International Journal of Thermophysics

Thermal Conductivity of Ionic Liquids: Measurement and Prediction

Froba, A. P.[Andreas P.], Rausch, M. H.[Michael H.], Krzeminski, K., Assenbaum, D.[Daniel], Wasserscheid, P.[Peter], Leipertz, A.[Alfred]
Int. J. Thermophys. 2010, 31, 11-12, 2059-2077
ABSTRACT
This study reports thermal-conductivity data for a series of [EMIM] (1-ethyl-3-methylimidazolium)-based ionic liquids (ILs) having the anions [NTf2] (bis(trifluoromethylsulfonyl)imide), [OAc] (acetate), [N(CN)2] (dicyanimide), [C(CN)3] (tricyanomethide), [MeOHPO2] (methylphosphonate), [EtSO4] (ethylsulfate), or [OcSO4] (octylsulfate), and in addition for ILs with the [NTf2]-anion having the cations [HMIM] (1-hexyl-3-methylimidazolium), [OMA] (methyltrioctylammonium), or [BBIM] (1,3-dibutylimidazolium). Measurements were performed in the temperature range between (273.15 and 333.15) K by a stationary guarded parallelplate instrument with a total measurement uncertainty of 3 % (k = 2). For all ILs, the temperature dependence of the thermal conductivity can well be represented by a linear equation. While for the [NTf2]-based ILs, a slight increase of the thermal conductivity with increasing molar mass of the cation is found at a given temperature, the [EMIM]- based ILs show a pronounced, approximately linear decrease with increasing molar mass of the different probed anions. Based on the experimental data obtained in this study, a simple relationship between the thermal conductivity,molar mass, and density is proposed for the prediction of the thermal-conductivity data of ILs. For this, also densities were measured for [EMIM][OAc], [EMIM][C(CN)3], and [HMIM][NTf2]. Themean absolute percentage deviation of all thermal-conductivity data for ILs found in the literature from the proposed prediction is about 7 %. This result represents a convenient simplification in the acquisition of thermal conductivity information for the enormous amount of structurally different IL cation/anion combinations available.
Compounds
# Formula Name
1 C8H11F6N3O4S2 1-ethyl-3-methylimidazolium bis((trifluoromethyl)sulfonyl)imide
2 C8H14N2O2 1-ethyl-3-methylimidazolium acetate
3 C8H11N5 1-ethyl-3-methylimidazolium dicyanamide
4 C10H11N5 1-ethyl-3-methyl-1H-imidazolium tricyanomethanide
5 C7H15N2O3P 1-ethyl-3-methylimidazolium methyl phosphonate
6 C8H16N2O4S 1-ethyl-3-methylimidazolium ethyl sulfate
7 C14H28N2O4S 1-ethyl-3-methylimidazolium octyl sulfate
8 C12H19F6N3O4S2 1-hexyl-3-methylimidazolium bis[(trifluoromethyl)sulfonyl]imide
9 C27H54F6N2O4S2 methyltrioctylammonium 1,1,1-trifluoro-N-[(trifluoromethyl)sulfonyl]methanesulfonamide
10 C13H21F6N3O4S2 1,3-dibutyl-1H-imidazolium bis((trifluoromethyl)sulfonyl)amide
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
  • 1
  • Thermal conductivity, W/m/K ; Liquid
  • Temperature, K; Liquid
  • Pressure, kPa; Liquid
  • Liquid
  • Parallel plate method
  • 9
  • POMD
  • 2
  • Thermal conductivity, W/m/K ; Liquid
  • Temperature, K; Liquid
  • Pressure, kPa; Liquid
  • Liquid
  • Parallel plate method
  • 9
  • POMD
  • 2
  • Refractive index (Na D-line) ; Liquid
  • Temperature, K; Liquid
  • Pressure, kPa; Liquid
  • Liquid
  • Standard Abbe refractometry
  • 4
  • POMD
  • 2
  • Mass density, kg/m3 ; Liquid
  • Temperature, K; Liquid
  • Pressure, kPa; Liquid
  • Liquid
  • VIBTUB:UFactor:4
  • 18
  • POMD
  • 3
  • Thermal conductivity, W/m/K ; Liquid
  • Temperature, K; Liquid
  • Pressure, kPa; Liquid
  • Liquid
  • Parallel plate method
  • 9
  • POMD
  • 4
  • Thermal conductivity, W/m/K ; Liquid
  • Temperature, K; Liquid
  • Pressure, kPa; Liquid
  • Liquid
  • Parallel plate method
  • 9
  • POMD
  • 4
  • Refractive index (Na D-line) ; Liquid
  • Temperature, K; Liquid
  • Pressure, kPa; Liquid
  • Liquid
  • Standard Abbe refractometry
  • 4
  • POMD
  • 4
  • Mass density, kg/m3 ; Liquid
  • Temperature, K; Liquid
  • Pressure, kPa; Liquid
  • Liquid
  • VIBTUB:UFactor:4
  • 19
  • POMD
  • 5
  • Thermal conductivity, W/m/K ; Liquid
  • Temperature, K; Liquid
  • Pressure, kPa; Liquid
  • Liquid
  • Parallel plate method
  • 9
  • POMD
  • 6
  • Thermal conductivity, W/m/K ; Liquid
  • Temperature, K; Liquid
  • Pressure, kPa; Liquid
  • Liquid
  • Parallel plate method
  • 9
  • POMD
  • 7
  • Thermal conductivity, W/m/K ; Liquid
  • Temperature, K; Liquid
  • Pressure, kPa; Liquid
  • Liquid
  • Parallel plate method
  • 9
  • POMD
  • 8
  • Thermal conductivity, W/m/K ; Liquid
  • Temperature, K; Liquid
  • Pressure, kPa; Liquid
  • Liquid
  • Parallel plate method
  • 9
  • POMD
  • 8
  • Mass density, kg/m3 ; Liquid
  • Temperature, K; Liquid
  • Pressure, kPa; Liquid
  • Liquid
  • VIBTUB:UFactor:4
  • 18
  • POMD
  • 8
  • Refractive index (Na D-line) ; Liquid
  • Temperature, K; Liquid
  • Pressure, kPa; Liquid
  • Liquid
  • Standard Abbe refractometry
  • 4
  • POMD
  • 9
  • Thermal conductivity, W/m/K ; Liquid
  • Temperature, K; Liquid
  • Pressure, kPa; Liquid
  • Liquid
  • Parallel plate method
  • 9
  • POMD
  • 10
  • Thermal conductivity, W/m/K ; Liquid
  • Temperature, K; Liquid
  • Pressure, kPa; Liquid
  • Liquid
  • Parallel plate method
  • 9