Abstract
Dehydrated ammonium carnallite was synthesized with bischofite from salt lake and ammonium chloride solution in a 1:1 molar ratio of MgCl2:NH4Cl, dehydrated at 160°C for about 4 h. The yield was above 85%. The product was then mixed with solid-state ammonium chloride with a 1:4 mass ratio for the further dehydration at 410°C. The decomposition of NH4Cl made a pressure of NH3 at 30.5 kPa to prevent the hydrolysis of ammonium carnallite. The anhydration of magnesium chloride was achieved at 700°C. The results showed that anhydrous magnesium chloride contains magnesium oxide in an amount that was less than 0.1% by weight. XRD pattern and SEM micrograph showed a good dispersion of ammonium carnallite and anhydrous magnesium chloride crystals with well-distributed big grains, just enough to meet the need for the production of magnesium metal in the electrolysis process.
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References
Yang Yuchun. The application of magnesium in automotive. Nonferrous Metals, 1999, 5, 45–49
Nishkawa Y. Development of electric products using magnesium alloy. Func Mater, 1999, 19(6): 21–27
Luo A., Renaud J., Nakatsugawa I. Magnesium casting for automobile applications. JOM, 1995, 47(7): 28–31
Gong Tao. Existing problem and further developing direction of magnesium industry in china. Light Metals, 1999, (5): 44–46
Shekhovtsov G., Shchegolev V., Devyatkin V., Tatakin A., Zabelin I. Magnesium electrolytic production process. TMS Annual Meeting, 2000, 31–34
Han Fengwen. The way to deal with a situation and corresponding suggestions of magnesium industry in china. Light Metals, 1999, (7): 40–44
Hu Zhongfeng. On technical scheme of Qinghai salt lake magnesium plant. Nonferrous MetalsDesign, 2003, 30(3): 15–18
Zhang Weiying. Methods of reducing production costs and saving energy consumption on production of magnesium by electrolysis. Nonferrous Mining Metallurgy, 1996, (4): 42–43
Shi Changxu, Li Hengde, Wang Dianzuo, Li Yiyi, Zuo Tieyong. A proposal on accelerating development of metallic magnesium industry in china. Meter Rev, 2001, 15(4): 5–6
Kipouros G. J., Sadoway D. R. A thermochemical analysis of the production of anhydrous MgCl2. J Light Metals, 2001, 1, 111–117
Chen Jianjun, Ma Yutao. Development and prospect of dehydration on bischofite. J Salt Lake Res, 1998, 6(2): 63–68
Berg C., Beyer M., Achatz U., Joos S., Niedner-Schatteburg G., Bondybey V.E. Stability and reactivity of hydrated magnesium cations. Cheml Phys, 1998, 239, 379–392
Wang Jishun, Gao Shiyang, Liu Zhutang. On the isothermal solubities of HCl-MgCl2-H2O and LiCl-MgCl2-H2O systems at −10°C. Chin J Appl Chem 1992, 9(4): 91–94
Dolezal H., Dehydration of Magnesium Chloride, US: 3962408, 1976, 6, 08
Xu Riyao, A Handbooks for Extractive Metallurgy of Nonferous Metals-Magnesium, Beijing: Metallurgical Industry Press, 1992, 111
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Translated from Chinese Journal of Applied Chemistry, 2005, 22(8) (in Chinese)
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Zhou, N., Chen, B., He, X. et al. Preparation of anhydrous magnesium chloride in a gas-solid reaction with ammonium carnallite. Front. Chem. China 1, 384–388 (2006). https://doi.org/10.1007/s11458-006-0046-5
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DOI: https://doi.org/10.1007/s11458-006-0046-5