Preparation of phase change materials for low temperature applications and investigation of their thermal properties

The depletion of mineral fuels, also known as fossil fuels, the fact that they take centuries to regenerate, as well as the damage they cause to the ecosystem, have been evaluated by various researchers for years. In the continuation of these researches, the tendency to alternative sources is increasing day by day. Alternative sources are hydro, geothermal, solar, wind, wood, plant residues, biomass, tides and waves. It is of great importance for the world that these resources are renewable and significantly reduce carbon emissions. However, the dependence of renewable energy sources on natural conditions causes discontinuous production. For this reason, scientists have turned to ways to store the energies they have obtained with renewable sources and the waste energies that cannot be used at present. Energy storage for these purposes can be expressed as the conservation of energy in different ways, such as electricity, heat or chemicals, in the device or storage area. Thermal storage is an energy storage method in which sensible heat storage (with temperature change only), latent heat storage (through phase change) or both can be done. Of these, the heat given or received by the material during the phase change with latent heat storage (GID) is realized with materials called phase change material (FDM) within the material, which have the appropriate heat capacity and can absorb or release energy by changing the phase at a certain temperature value. In this study, it is aimed to prepare a new composite phase change material for use in low temperature energy applications. For this, a new latent heat storage material was produced by impregnating the capric acid-based composite phase change materials into granular pumice in a single step by impregnation method. In this context, the thermal, morphological and chemical properties of the prepared capric acid added composite FDM; It was investigated by Differential Scanning Calorimetry (DSC), Scanning Electron Microscopy (SEM) and Fourier Transform Infrared (FT-IR) spectroscopy analysis. The latent heat of melting of the obtained composite material was found to be 36.18 kJ/kg, and the peak temperatures of melting and crystallization were found to be 31.14 °C and 25.32 °C, respectively. As a result, it is evaluated that the obtained composite PCM may be a suitable candidate for various practical application areas at low-medium temperatures.