镧钐渣焙烧变质协同熔盐电化学法分离稀土La/Sm研究  

Study on the separation of rare earth La/Sm by roasting modification of lanthanum samarium slag and electrochemical method of molten salt

作　　者：黄浩添 王旭[1] 廖春发[1] 钱勇辉 赖江源 HUANG Haotian;WANG Xu;LIAO Chunfa;QIAN Yonghui;LAI Jiangyuan(Faculty of Materials,Metallurgy and Chemistry,Jiangxi University of Science and Technology,Ganzhou 341000,Jiangxi,China)

机构地区：[1]江西理工大学材料冶金化学学部,江西赣州341000

出　　处：《有色金属科学与工程》2025年第2期163-170,共8页Nonferrous Metals Science and Engineering

基　　金：国家自然科学基金资助项目(52074134,52174335)。

摘　　要：稀土金属镧热还原渣中La元素再生利用对稀土二次资源高值利用具有重要意义。本文主要研究镧钐渣(LaSlag)焙烧变质和(LiF-LaF_(3))_(eut).氟化物熔盐载体中电化学还原分离La/Sm规律,探索阴极电流密度和温度对(LiF-LaF_(3))_(eut).-LaSlag电还原参数(槽电压、反电动势和过电位)的影响,为优化还原外部条件提供依据。结果表明:镧钐渣在不低于823 K条件下,经焙烧改性可全部脱氢转型为稳定的稀土镧/钐氧化物。在温度1 223~1 323 K范围内,当(LiF-LaF_(3))_(eut).-LaSlag体系电还原过程阴极电流密度在低于4.0 A/cm^(2)范围内递增时,体系的槽电压、过电位也逐渐增加,阳极效应周期则逐渐缩短;当电流密度高于4.0 A/cm^(2)后,体系的槽电压、过电位和阳极效应周期趋于稳定。当阴极电流密度一定时,阴极过电位和阳极效应周期影响较小,低于1 273 K时体系槽电压和反电动势随温度升高而小幅度降低,温度高于1 273 K时则趋于稳定。The regeneration and utilization of La in its thermal reduction slag of rare earth metal are of great significance for the high-value utilization of rare earth secondary resources.In this paper,the roasting modification of lanthanum samarium slag (LaSlag) and the electrochemical reduction separation mechanisms of La/Sm in (LiF-LaF_(3))_(eut) fluoride molten salt carrier were studied.The effect of cathode current density and temperature on the (LiF-LaF_(3))_(eut).-LaSlag electroreduction parameters (cell voltage,back electromotive force and overpotential) was explored to provide a basis for optimizing external reduction conditions.The results showed that all the lanthanum-samarium slag could be dehydrogenated to stable rare-earth lanthanum-samarium oxides by roasting modification at no less than 823 K.Within the temperature range of 1 223~1 323 K,during the electroreduction process of the(LiF-LaF_(3))eut.-LaSlag system,as the cathode current density increased within the range of less than 4.0 A/cm^(2),the cell voltage and overpotential of the system also gradually increased,while the anode effect period progressively shortened.When the current density was higher than 4.0 A/cm^(2),its three electroreduction parameters tended to be stable.As the cathode current density remained constant,the effect of cathode overpotential and anode effect period was relatively small.Below 1 273 K,the cell voltage and back electromotive force decreased slightly with the increase in temperature,while they tended to be stable at temperatures above 1 273 K.

关 键 词：镧钐渣 稀土La/Sm 熔盐 反电动势 过电位 

分 类 号：TF845[冶金工程—有色金属冶金]