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 

机构地区：[1]Korea Institute of Geoscience and Mineral Resources,124 Gwahak-ro Yuseong-gu,Daejeon 34132,Republic of Korea [2]Department of Materials Science and Engineering,Seoul National University,1 Gwanak-ro,Gwanak-gu,Seoul 08826,Republic of Korea [3]Department of Resources Engineering,University of Science and Technology,217 Gajeong-ro Yuseong-gu,Daejeon 34113,Republic of Korea [4]School of Materials Science and Engineering,Pusan National University,2 Busandaehak-ro,Geumjeong-gu,Busan 46241,Republic of Korea

出　　处：《Journal of Magnesium and Alloys》2023年第4期1308-1320,共13页镁合金学报（英文）

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).

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.

关 键 词：High-purity magnesium DOLOMITE Magnesium oxide Electrolytic process Copper metal cathode Vacuum distillation 

分 类 号：TF822[冶金工程—有色金属冶金]