Thermal conductivity and thermal diffusivity of Pyrrolidinium-Basedlonic liquids at atmospheric pressure

The thermal conductivity of two pyrrolidinium-based ionic liquids (ILs) 1-propyl-1-methylpyrrolidinium bis(trifluoromethanesulfonyl)imide (short name is [C(3)C(1)pyr][NTf2]) and 1-butyl-1-methylpyrrolidinium bis(trifluoromethanesulfonyl)imide (short name is [C4C1]pyr][NTf2]) have been measured over the temperature range from (279-438) K at atmospheric pressure. Measurements were made using the steady-state hot-wire technique. The combined expanded uncertainty of the temperature and thermal conductivity measurements at the 95% confidence level with a coverage factor of k=2 is estimated to be 0.02 K and 3.2%, respectively. The measured thermal conductivities (A) together with our previously reported heat capacity (C-p) and density (rho) data were used to calculate thermal diffusivity (a) of the ILs using well-known thermodynamic relation a = lambda/rho Cp.The new measured values of the thermal conductivity have been also used to check the reliability and accuracy of the various predictive methods (generalized model, group contribution method). (C) 2018 Elsevier B.V. All rights reserved.