Marc Majó, Ricard Sánchez, Pol Barcelona, Jordi García, Ana Inés Fernández and Camila Barreneche.
https://doi.org/10.3390/molecules26040982
Molecules 2021, 26, 982
Quartile Q2, Impact 3.267
The use of adequate thermal energy storage (TES) systems is an efficient way to achieve thermal comfort in buildings reducing the cooling and heating demand. Besides, deploy phase change materials (PCM) to meet and enhance the TES needs is highly effective and widely studied. In this paper, a study of the degradation of two fatty acids is presented, capric and myristic acids, in order to evaluate whether their thermo-physical properties are affected throughout time during service. This was carried out by means of two different types of thermal treatments: degradation at constant temperature (thermal stability test), 60 ºC during 100 h and 500 h, and degradation with heating and cooling cycling (thermal cycling stability), between a temperature range from 15 ºC to 70 ºC with 0.5 ºC/min ramp during 500 and 1000 cycles. Despite no significant changes were measured for myristic acid, experimental results revealed a decrease of melting enthalpy of 6.6% in capric acid thermally treated for 500 h. Evidences of chemical degradation were found that might explain the decrease in thermophysical properties during use.
Table 1. DSC results: melting temperature and melting thermal and cycling stability results. ∆Hm [%] are melting enthalpy variation expressed in % regarding the initial value and ∆Tm [ºC] are temperature increment in the different treatments.
Funding
This research was partially funded by the Ministerio de Economía y Competitividad de España RTI2018-093849-B-C32 (MINECO/FEDER). The authors would like to thank the Catalan Government for the quality accreditation given to their research group (DIOPMA 2017 SGR 0118). DIOPMA is certified agent TECNIO in the category of technology developers from the Government of Catalonia”.
Research line: Materials for Energy
Projects associated: MATCE: Methodology for analysis of thermal energy storage technologies towards a circular economy