The role of chemical additives to the phase change process of CaCl₂.6H₂O to optimize its performance as latent heat energy storage system

CaCl₂.6H₂O is one of salt hydrate based phase change material (PCM) which is suitable for room air-temperature stabilizer because it has the melting temperature just above the human comfort zone temperature (T_m ∼ 29 ^oC) and a relatively large heat entalphy (AH ∼ 190 kJ/kg). This paper reports the role of the type of chemical additives to PCM CaCl₂.6H₂O to the phase change process throughout the solidification process or heat release in order to optimize its performance as latent heat energy storage system. In this research we used several kinds of chemical additive, namely SrCl₂.6H₂O (1.0 wt%), BaCO₃ (0.5 wt%), and K₂CO₃ (0.5 wt%). In terms of its latent time for phase change process the order the effectiveness of those chemical additives are reduced from SrCl₂.6H₂O, BaCO₃and K₂CO₃. We found that this is also related to their role in suppression supercooling and phase separation effects which occurs during crystallization process of CaCl2.6H2O.