REN Xuetan 1, HOU Laiguang 2, LIU Yanchun 2, ZENG Lingke 3
（1.School of Materials Science and Engineering, Southwest University of Science and Technology, Mianyang, Sichuan
621010, China; 2. Guangzhou Redsun Gas Appliances Co.,Ltd., Guangzhou, Guangdong 510435, China; 3. School of Materials Science and Engineering, South China University of Technology, Guangzhou, Guangdong 510640, China ）
Abstract: The feasibility of mullite as the matrix for sulfate salts-based phase change materials was studied by analyzing the thermophysical properties of sodium sulfate and potassium sulfate phase change materials such as their thermodynamic stability and saturated vapor pressure. The results indicated sodium sulfate and potassium sulfate are difficult to decompose with low equilibrium constant at 1100℃. Sodium sulfate is a promising phase change material for its low saturated vapor pressure even at 1200℃ ; its mixed molten salts also exhibit very low vapor pressure; the calculated data and the experimental data coincide. The design and calculation of the relevant parameters can benefit the practical application of phase change materials.
Key words: sulfate salts; thermophysical properties; phase change; energy storage