Compounding MgCl2·6H2O with NH4Al(SO4)2·12H2O or KAl(SO4)2·12H2O to Obtain Binary Hydrated Salts as High-Performance Phase Change Materials

Molecules

Xiaoming Fang¹  Ziye Ling¹  Wanchun Sun¹  Yan Zhou¹  Zhengguo Zhang¹  Jinxin Feng¹ 

[1] Key Laboratory of Enhanced Heat Transfer and Energy Conservation, The Ministry of Education, School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou 510640, China;

关键词: latent heat storage;    phase change material;    magnesium chloride hexahydrate;    aluminum ammonium sulfate dodecahydrate;    aluminum potassium sulfate dodecahydrate;   

DOI  :  10.3390/molecules24020363

来源: DOAJ

【 摘 要 】

Developing phase change materials (PCMs) with suitable phase change temperatures and high latent heat is of great significance for accelerating the development of latent heat storage technology to be applied in solar water heating (SWH) systems. The phase change performances of two mixtures, NH₄Al(SO₄)₂·12H₂O-MgCl₂·6H₂O (mixture-A) and KAl(SO₄)₂·12H₂O-MgCl₂·6H₂O (mixture-B), were investigated in this paper. Based on the DSC results, the optimum contents of MgCl₂·6H₂O in mixture-A and mixture-B were determined to be 30 wt%. It is found that the melting points of mixture-A (30 wt% MgCl₂·6H₂O) and mixture-B (30 wt% MgCl₂·6H₂O) are 64.15 °C and 60.15 °C, respectively, which are suitable for SWH systems. Moreover, two mixtures have high latent heat of up to 192.1 kJ/kg and 198.1 kJ/kg as well as exhibit little supercooling. After 200 cycles heating-cooling experiments, the deviations in melting point and melting enthalpy of mixture-A are only 1.51% and 1.20%, respectively. Furthermore, the XRD patterns before and after the cycling experiments show that mixture-A possesses good structure stability. These excellent thermal characteristics make mixture-A show great potential for SWH systems.

【 授权许可】

Unknown