Synthesis of microencapsulated palmitic acid with titania shell for thermal energy storage systems

Nowadays, increasing energy consumption and the shortage of fossil fuels is a worrying issue for human society. Phase change materials (PCMs) which are used for thermal energy storage, are able to store a large amount of latent heat at their phase change temperature1. Encapsulation of phase change materials as micro/nano-capsules prevents thermal dissipation2. Fatty acids are one of the organic phase change materials that have a different melting temperature range that can be used depending on the application3. In this work, we prepared PCM microcapsules which contain PA (palmitic acid) as core and TiO2 as shell materials. Microcapsules were synthesized using a sol-gel method, which is a physical-chemical method by changing the value of pH in the range of 9-10. The particle size and microstructure of microencapsulated phase change material (MPCM) were investigated by scanning electronic microscope (SEM). Fourier transformation infrared spectroscope (FT-IR) that examined chemical structure, illustrated that palmitic acid was well microencapsulated in TiO2 shell. The thermal leakage test showed negligible leakage. The results show that microcapsules have good thermal stability and can be used to store thermal energy in a temperature range of 62-65°C.

کلیدواژه ها:

Phase change materials ، Thermal energy storage ، Palmitic acid ، TiO2 ، Sol-gel