Heat capacity, thermal conductivity and thermal diffusivity of aqueous sulfolane solutions

In this work, the thermal properties including molar heat capacity, thermal conductivity, and thermal diffusivity of aqueous sulfolane solutions were measured at temperatures ranging from (303.15 to 353.15) K and atmospheric pressure. The measurements were carried out for the entire range of mole fractions of sulfolane in water. Molar excess heat capacities as well as excess thermal conductivities and excess thermal diffusivities were calculated from the experimental values and correlated as a function of mole fraction and temperature using the Redlich–Kister equation. Employing the heat capacity, thermal conductivity and thermal diffusivity of pure water as the solvent, the corresponding experimental values obtained for the investigated solutions were also correlated with temperature and concentration by a modified Setchenow equation. Results show comparable accuracy of both models in correlating all three experimental thermal properties.