Inorganic Chemicals Industry >

2024 , Vol. 56 >Issue 2: 51 - 56

DOI: https://doi.org/10.19964/j.issn.1006-4990.2023-0147

Research & Development

Study on electrochemical properties of magnesium chloride molten salt hydrates

  • DONG Mingzhe ,
  • LI Kexin ,
  • YE Xiushen ,
  • MA Zhen ,
  • LI Shengting ,
  • LI Quan ,
  • WU Zhijian
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  • 1.Key Laboratory of Comprehensive and Highly Efficient Utilization of Salt-lake Resources，Qinghai Institute of Salt-lakes，Chinese Academy of Sciences，Xining 810008，China
    2.Key Laboratory of Salt-lake Resources Chemistry of Qinghai Province，Xining 810008，China
    3.Qinghai Salt Lake Industry Co. ，Ltd. ，Golmud 816000，China
    4.University of Chinese Academy of Sciences，Beijing 100049 China

Received date: 2023-03-16

  Online published: 2024-02-06

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Abstract

Molten salt hydrates（MSHs） are inorganic salt melts in general，in which the molar ratio of water-to-salt is less than or equal to the hydration number or coordination number of the cation.To comprehend the dehydration procedure and mechanism of inorganic salt hydrates thoroughly，it is essential to study their characteristics.The conductivity of the MgCl2-H2O system at various temperatures was measured，as well as the lowest temperature at which the system with different compositions existed in liquid form.By employing the cyclic voltammetry technique，the electrochemical characteristics of the MgCl2-H2O and MgCl2-KCl-H2O systems were comprehensively investigated.The conductivity was increased initially and then was steadily decreased when the water content of the MgCl2-H2O system was decreased at the same temperature.The conductivity was gradually increased when the temperature was increased at the same water content in dilute solution.The conductivity was decreased with the decrease of water content in concentrated solutions or MSHs at the same temperature；The anodic and cathodic currents in the MgCl2-H2O system were dramatically increased with increasing water content after reaching the oxidation or reduction potential in cyclic voltammetry tests.The concentration of Cl- in the molten salt hydrate system was increased after adding KCl，and Cl- replaced some water molecules in the hydrated magnesium ions，making hydrogen reduction easier.In the dehydration of MgCl2·6H2O，the addition of Cl- could decrease the hydrolysis reaction of MgCl2·6H2O，making it more conducive to dehydration of MgCl2·6H2O.

Key words： magnesium chloride; molten salt hydrate; conductivity; cyclic voltammetry

Cite this article

DONG Mingzhe , LI Kexin , YE Xiushen , MA Zhen , LI Shengting , LI Quan , WU Zhijian . Study on electrochemical properties of magnesium chloride molten salt hydrates[J]. Inorganic Chemicals Industry, 2024 , 56(2) : 51 -56 . DOI: 10.19964/j.issn.1006-4990.2023-0147

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