Production of high-purity Mg metal from dolomite through novel molten salt electrolysis and vacuum distillation

作     者：Hyeong-Jun Jeoung Tae-Hyuk Lee Jin-Young Lee Kyung-Woo Yi Jungshin Kang 

作者机构：Korea Institute of Geoscience and Mineral Resources124 Gwahak-ro Yuseong-guDaejeon 34132Republic of Korea Department of Materials Science and EngineeringSeoul National University1 Gwanak-roGwanak-guSeoul 08826Republic of Korea Department of Resources EngineeringUniversity of Science and Technology217 Gajeong-ro Yuseong-guDaejeon 34113Republic of Korea School of Materials Science and EngineeringPusan National University2 Busandaehak-roGeumjeong-guBusan 46241Republic of Korea 

出 版 物：《Journal of Magnesium and Alloys》 (镁合金学报（英文）)

年 卷 期：2023年第11卷第4期

页      面：1308-1320页

核心收录：

学科分类：080603[工学-有色金属冶金] 0809[工学-电子科学与技术（可授工学、理学学位）] 08[工学] 0806[工学-冶金工程] 0703[理学-化学] 

基　　金：supported by the National Research Councile of Science and Technology funded by the Korean Ministry of Industry in Korea(Project Nos.:1711173260,22-3803) the Korea Evaluation Institute of Industrial Technology funded by the Korean Ministry of Industry in Korea(Project Nos.:1415179713,20011157). 

主　　题：High-purity magnesium Dolomite Magnesium oxide Electrolytic process Copper metal cathode Vacuum distillation 

摘      要：In this study,a novel Mg production process for producing high-purity Mg metal from dolomite was developed.When the electrolysis of calcined dolomite was conducted using Cu cathode and C anode in MgF_(2)–LiF molten salt at 1083–1173 K by applying an average current of 1.42–1.46 A for 9.50–21.0 h,the current efficiency of 66.4–88.6%was obtained.The produced Mg alloys consisted of MgCu_(2)and Cu(Mg)or MgCu_(2)and CuMg_(2)phases,depending on the Mg concentration in the Mg alloy.When the electrolysis of calcined dolomite was conducted in MgF_(2)–LiF–CaF_(2)molten salt at 1083 K,the current efficiency was 40.9–71.4%,owing to undesired reactions such as electroreduction of Ca^(2+)or/and CO_(3)^(2−)ions.Meanwhile,the current efficiency increased from 40.9%to 63.2%by utilizing a Pt anode,because the occurrence of CO_(3)^(2−)ions in the molten salt was prevented.After vacuum distillation of the obtained Mg alloys at 1300 K for 10 h,Mg metal with a purity of 99.9996–99.9998%was produced.Therefore,the feasibility of this novel process for the production of high-purity Mg metal from dolomite was demonstrated.