Characterization and Reliability of Caprylic Acid-Stearyl Alcohol Binary Mixture as Phase Change Material for a Cold Energy Storage System

Hamza Ayaz; Veerakumar Chinnasamy; Honghyun Cho

doi:10.3390/ma14237418

Characterization and Reliability of Caprylic Acid-Stearyl Alcohol Binary Mixture as Phase Change Material for a Cold Energy Storage System

Materials (Basel). 2021 Dec 3;14(23):7418. doi: 10.3390/ma14237418.

Authors

Hamza Ayaz¹, Veerakumar Chinnasamy², Honghyun Cho²

Affiliations

¹ Graduate School, Chosun University, 309 Pilmundaero, Gwangju 61452, Korea.
² Department of Mechanical Engineering, Chosun University, 309 Pilmundaero, Gwangju 61452, Korea.

Abstract

This study reports the in-depth investigation of the thermophysical properties and thermal reliability of caprylic acid-stearyl alcohol (CA-SA) eutectic phase change material (PCM) for cooling applications. The phase diagram of CA-SA showed a eutectic point at a 90:10 molar ratio. The onset melting/freezing temperature and latent heat of fusion of caprylic acid-stearyl alcohol from the differential scanning calorimetry (DSC) were 11.4 °C/11.8 °C and 154.4/150.5 J/g, respectively. The thermal conductivity for the prepared eutectic PCM in the solid phase was 0.267 W/m.K (0 °C), whereas, in the liquid phase, it was 0.165 W/m.K (20 °C). In addition, the maximum relative percentage difference (RPD) marked at the end of 200 thermal cycles was 5.2% for onset melting temperature and 18.9% for phase change enthalpy. The Fourier transform infrared spectroscopy (FT-IR) result shows that the eutectic PCM holds good chemical stability. Corrosion tests showed that caprylic acid-stearyl alcohol could be a potential candidate for cold thermal energy storage applications.

Keywords: cold thermal energy storage (CTES); corrosion test; fatty acid; fatty alcohol; phase change material (PCM); thermal reliability.