铝电解过程中锂元素的阴极渗透机理

doi:10.12068/j.issn.1005-3026.2021.01.010

东北大学学报（自然科学版） ›› 2021, Vol. 42 ›› Issue (1): 62-67.DOI: 10.12068/j.issn.1005-3026.2021.01.010

铝电解过程中锂元素的阴极渗透机理

王耀武¹，尤晶²，彭建平¹，狄跃忠¹

(1.东北大学冶金学院，辽宁沈阳110819； 2.辽宁科技学院，辽宁本溪117004)

出版日期:2021-01-15 发布日期:2021-01-13
通讯作者: 王耀武
作者简介:王耀武(1980-)，男，河北保定人，东北大学副教授.
基金资助:
国家重点研发计划项目(2018YFC1901905)；国家自然科学基金资助项目(51704150，51774080).

Cathode Permeation Mechanism of Lithium in Aluminum Electrolysis

WANG Yao-wu¹， YOU Jing²， PENG Jian-ping¹， DI Yue-zhong¹

1. School of Metallurgy， Northeastern University， Shenyang 110819， China; 2. Liaoning Institute of Science and Technology， Benxi 117004， China.

Online:2021-01-15 Published:2021-01-13
Contact: WANG Yao-wu
About author:-
Supported by:
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摘要/Abstract

摘要： 铝电解生产过程中，由于氧化铝中含有少量的氧化锂导致电解质中氟化锂含量升高，锂元素向阴极内衬中渗透.通过X射线衍射分析与扫描电镜分析，对电解质和阴极炭块中锂元素的存在形式进行了研究，探讨了铝电解过程中锂元素的阴极渗透机理.结果表明:电解质中的锂主要以LiNa₂AlF₆形式存在；电解过程中，电解质中的部分锂离子被铝还原为金属锂并进入铝液中，铝液中锂摩尔分数与电解质中的氟化锂摩尔分数成正比；电解质中的锂主要以氟化物形式通过阴极炭块中的开气孔和裂缝向阴极炭块中渗透，铝液中的锂不会通过铝液向阴极炭块内部扩散.

关键词: 铝电解；氟化锂；渗透机理；铝热还原；阴极炭块

Abstract: In the process of aluminum electrolysis， the proportion of lithium fluoride in electrolyte increases gradually due to the existence of a small amount of lithium oxide in alumina， and the lithium element permeates the cathode lining. The existent forms of lithium element in electrolyte and cathode carbon blocks were analyzed by X-ray diffraction and scanning electron microscope， and the cathode permeation mechanism of lithium element in aluminum electrolysis was studied. The results show that the lithium element in electrolyte is primarily in the form of LiNa₂AlF₆. Some lithium ions in molten electrolyte are reduced to lithium metal by aluminum and the Mole fraction of lithium in aluminum liquid is positively related to the Mole fraction of lithium fluoride in electrolyte. The lithium in the electrolyte permeating the cathode carbon blocks through the pores and cracks in the cathode carbon blocks is mainly in the form of fluorides. The lithium in the aluminum liquid cannot diffuse into the cathode carbon blocks.

Key words: aluminum electrolysis； lithium fluoride； permeation mechanism； aluminothermic reduction； cathode carbon blocks

中图分类号:

TF131.1

王耀武，尤晶，彭建平，狄跃忠. 铝电解过程中锂元素的阴极渗透机理[J]. 东北大学学报（自然科学版）, 2021, 42(1): 62-67.

WANG Yao-wu， YOU Jing， PENG Jian-ping， DI Yue-zhong. Cathode Permeation Mechanism of Lithium in Aluminum Electrolysis[J]. Journal of Northeastern University(Natural Science), 2021, 42(1): 62-67.

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铝电解过程中锂元素的阴极渗透机理

Cathode Permeation Mechanism of Lithium in Aluminum Electrolysis

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