Isobaric volumetric heat capacities (?p) of the ionic liquids 1-hexyl (or octyl)-3-methylimidazolium bis(trifluoromethylsulfonyl)imide, [C6mim][Tf2N] and [C8mim][Tf2N], have been measured in the temperature range of 323 ? T/K ? 573 with a Tian-Calvet type differential calorimeter at a pressure of 10 MPa. Isobaric massic (cp) and molar (Cp) heat capacities were calculated from the ?p values using densities estimated from literature data. The present Cp values increase approximately linearly with temperature over the investigated range. Where comparison is possible, the present results are in excellent agreement with literature data obtained by adiabatic calorimetry but disagree markedly (by up to 7 %) with those measured by differential scanning calorimetry. Both compounds show evidence of decomposition at T 535 K, which is in approximate agreement with recent slow scan thermogravimetric measurements but is about 85 K lower than suggested by previous fast scan data.
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
Heat capacity at constant pressure per volume, J/K/m3 ; Liquid
Temperature, K; Liquid
Pressure, kPa; Liquid
Liquid
Tian-Calvet differential microcalorimeter
20
POMD
2
Heat capacity at constant pressure per volume, J/K/m3 ; Liquid