In this study, long chain diesters of fatty alcohols were synthesized for use in thermal energy storage applications. Long-chain diesters of adipic acid were proposed for the first time in this study to be used as phase change material (PCM). For this purpose, ditetradecyl adipate (DTA) and dioctadecyl adipate (DOA) were synthesized as novel solid-liquid PCMs by means of the direct esterification reaction of adipic acid with 1-tetradecanol and 1-octadecanol. The reaction was yielded at around 90% as an average at the end of 6 hours. The DTA and DOA were characterized chemically using FT-IR and 1HNMR techniques as the energy storage properties, total enthalpy, and specific heat (Cp) capacity values were determined by DSC analysis. Melting temperatures and enthalpies of DTA and DOA were measured as 44 and 60 C respectively; and 142.4 and 186.2 Jg-1 respectively. Total enthalpy calculation showed the latent heat storage capacity along with sensible heat capacity of fatty alcohols and long-chain diesters between 0 and 80 C. Cp values of fatty alcohols and long-chain diesters also calculated for solid and liquid phase separately. TGA analysis was performed to determine thermal stability of the esters. DTA and DOA compounds were found stable up to 248.3 and 342.5 C respectively. Thermal cycling test was applied to the materials and it was found that DTA and DOA are both found stable after 1000 times accelerated thermal cyclings. According to the results obtained, DTA and DOA with high energy storage capacity are promising to be used as new solid-liquid PCMs in thermal energy storage applications for medium temperature applications.
Primary Language | English |
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Journal Section | Natural Sciences |
Authors | |
Publication Date | March 22, 2020 |
Submission Date | January 2, 2020 |
Acceptance Date | January 31, 2020 |
Published in Issue | Year 2020 |