Phase transition characteristics and supercooling suppression of erythritol with organic salts as nucleating agents

Abstract

The main aim of this paper is to mitigate the supercooling of erythritol using organic salts as nucleating agents. The pure erythritol exhibits significant volume effects and a strong supercooling tendency. When the aspect ratio of the ET is small, a metastable phase transition plateau at 105 °C can be observed, and then, the metastable crystal slowly transforms into a stable crystal. Experimental results reveal that calcium pimelate (CaPi) has a positive influence on the supercooling elimination of erythritol. The 1 % CaPi/erythritol composite phase change material (CPCM) melts at 118 °C and solidifies at 109 °C with the latent heat of 344.86 J/g and 281.8 J/g, respectively. Due to the improved crystallization kinetics, the supercooling phenomenon measured by T-history method is basically eliminated. The melting heat is >300 J/g and the change of phase change temperature is less after 50 cycles. In order to simulate the real environment, the CPCM cools down by room temperature in air, and the chemical stability is good. The thermal conductivity of 1 % CaPi/ET increases by 23.2 %. In total, the CaPi/erythritol CPCM is a new candidate to be used in waste heat recovery, solar energy medium temperature heat collection and other fields.