The effect of hydrophilic modification of expanded graphite on the thermophysical properties of magnesium chloride hexahydrate

  • Yecheng Qian
  • Yue Zhang
  • Jinhe SunEmail author
  • Chao Song
  • Yan Jing
  • Fei Shao
  • Yongzhong JiaEmail author
  • Zhengyuan Tao
  • Xingquan Wang
  • Hong Liu


Magnesium chloride hexahydrate, as a phase change materials, is investigated usually to store solar energy. Here, the effect of hydrophilic modification of expanded graphite with Triton X-100 on the thermophysical properties of magnesium chloride hexahydrate was presented. Differential scanning calorimetry, scanning electron microscope, Fourier transform infrared spectroscopy and thermal gravimetric analysis, etc., were used. The magnesium chloride hexahydrate/hydrophilic expanded graphite composite phase change materials had more excellent thermal characteristics than magnesium chloride hexahydrate/expanded graphite composite phase change materials and pure magnesium chloride hexahydrate. The results showed that hydrophilic expanded graphite could better promote the endothermic and exothermic properties of magnesium chloride hexahydrate. After hydrophilic modification, the composites with higher melting enthalpy, better thermal conductivity and less supercooling were obtained. And the leakage test demonstrated that the hydrophilic modification of expanded graphite can reduce the leakage of magnesium chloride hexahydrate powerfully.


Expanded graphite Hydrophilic expanded graphite Magnesium chloride hexahydrate Phase change materials 



The work was supported by the National Key R&D Program of China (No. 2018YFC1903804-02), National Natural Science Foundation of China (20901082, U1407205) and Youth innovation Promotion Association of CAS (2015351).


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Copyright information

© Akadémiai Kiadó, Budapest, Hungary 2019

Authors and Affiliations

  1. 1.Key Laboratory of Comprehensive and Highly Efficient Utilization of Salt Lake Resources, Qinghai Institute of Salt LakesChinese Academy of SciencesXiningChina
  2. 2.Qinghai Engineering and Technology Research Center of Comprehensive Utilization of Salt Lake ResourcesXiningChina
  3. 3.University of Chinese Academy of SciencesBeijingChina
  4. 4.Qinghai UniversityXiningChina
  5. 5.Qinghai Salt Chemicals Supervision and Inspection CenterGeermuChina

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