Thermal properties of n-pentadecane, n-heptadecane and n-nonadecane in the solid/liquid phase change region

• Thermal properties of n-pentadecane, n-heptadecane and n-nonadecane in both solid and liquid phases are reported.
• Thermal conductivities of both solid and liquid phases were measured by the hot wire technique.
• Heat capacity, enthalpies and temperatures of transition were measured by Differential Scanning Calorimetry.
• X-Ray diffraction study was used to characterize the two solid phases of the studied odd-numbered n-alkanes.
• The results are useful in the design of PCM (Phase Change Materials) for energy recovery and/or storage.

The thermal properties including the thermal conductivity (λ), the specific heat (cp), the melting and crystallization temperatures together with their corresponding transition heat enthalpies of the odd-numbered linear alkane hydrocarbons n-pentadecane, n-heptadecane and n-nonadecane were measured in both the solid and liquid phases using the transient hot wire and the differential scanning calorimetry (DSC) techniques. The obtained results were compared with available literature data. Discussions were based also on the X-ray diffraction spectra of the three n-alkanes carried out at different temperatures and including both solid and liquid phases. A discontinuity of λ is observed at the solid - liquid phase transition of the three n-alkane hydrocarbons.