NaCl和LiF对低温铝电解电流效率的影响  

Effect of NaCl and LiF on current efficiency of low temperature aluminum electrolysis

作　　者：薛正铎 郭不拘 牛子儒 张元坤 刘爱民 石忠宁 Xue Zhengduo;Guo Buju;Niu Ziru;Zhang Yuankun;Liu Aimin;Shi Zhongning(Northeastern University School of Metallurgy,Shenyang 110819,China;Northeastern University State Key Laboratory of Rolling and Automation,Shenyang 110819,China)

机构地区：[1]东北大学冶金学院,沈阳110819 [2]东北大学轧制技术及连轧自动化国家重点实验室,沈阳110819

出　　处：《材料与冶金学报》2024年第1期16-22,共7页Journal of Materials and Metallurgy

基　　金：国家自然科学基金项目(52074084)。

摘　　要：低温铝电解是铝电解工艺的重要研究方向,熔盐体系的组成对电解温度和电流效率影响较大.为了获得较优的低温熔盐体系组成,在NaF-AlF_(3)-CaF_(2)-Al_(2)O_(3)熔盐体系中添加NaCl和LiF,在840~880℃下电解4 h,分别分析添加剂和Al_(2)O_(3)的质量分数对电流效率的影响.结果表明:添加10%(质量分数,下同)NaCl时电流效率为72.5%,与传统NaF-AlF_(3)-CaF_(2)-Al_(2)O_(3)熔盐体系电解4 h的电流效率相比提高了16.4%;添加2.5%NaCl-7.5%LiF,5%NaCl-5%LiF,7.5%NaCl-2.5%LiF时电流效率约为68%;添加10%LiF时电流效率为57.8%;当Al_(2)O_(3)质量分数为2%时,NaF-AlF_(3)-5%CaF_(2)-10%NaCl-5%LiF熔盐体系电解2 h的电流效率为48.1%,与Al_(2)O_(3)质量分数为3%时的电流效率相比提高了5.2%.Low temperature aluminum electrolysis is an important research area for energy saving in aluminum electrolysis technology.The composition of the molten salt has a significant effect on the electrolysis temperature and current efficiency.In order to obtain the optimal low-temperature molten salt systems,NaCl and LiF have been added to the NaF-AlF_(3)-CaF_(2)-Al_(2)O_(3)molten salt systems,and the electrolysis has been conducted at 840~880℃for 4 h.The influences of additive and alumina mass fraction on the current efficiency have been analyzed.The results show that when 10%(mass fraction,the same as below)NaCl is added the current efficiency is 72.5%,which is 16.4%higher than that of the traditional NaF-AlF_(3)-CaF_(2)-Al_(2)O_(3)molten salt system.When 2.5%NaCl-7.5%LiF,5%NaCl-5%LiF,and 7.5%NaCl-2.5%LiF are added,the current efficiency is approximately 68%.When 10%LiF is added,the current efficiency is 57.8%.When the mass fraction of Al_(2)O_(3)is 2%,the current efficiency during NaF-AlF_(3)-5%CaF_(2)-10%NaCl-5%LiF molten salt systems electrolysis for 2 h is 48.1%,which is 5.2%higher than that of the Al_(2)O_(3)with the mass fraction of 3%.

关 键 词：低温铝电解 电流效率 NACL LIF 

分 类 号：TF572[冶金工程—钢铁冶金]