Recovery and separation of rare earth elements by molten salt electrolysis

Tai-qi Yin; Yun Xue; Yong-de Yan; Zhen-chao Ma; Fu-qiu Ma; Mi-lin Zhang; Gui-ling Wang; Min Qiu

doi:10.1007/s12613-020-2228-4

Volume 28 Issue 6

Jun. 2021

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Article Navigation > International Journal of Minerals, Metallurgy and Materials > 2021 > 28(6): 899-914

Tai-qi Yin, Yun Xue, Yong-de Yan, Zhen-chao Ma, Fu-qiu Ma, Mi-lin Zhang, Gui-ling Wang, and Min Qiu, Recovery and separation of rare earth elements by molten salt electrolysis, Int. J. Miner. Metall. Mater., 28(2021), No. 6, pp. 899-914. https://doi.org/10.1007/s12613-020-2228-4

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Tai-qi Yin, Yun Xue, Yong-de Yan, Zhen-chao Ma, Fu-qiu Ma, Mi-lin Zhang, Gui-ling Wang, and Min Qiu, Recovery and separation of rare earth elements by molten salt electrolysis, Int. J. Miner. Metall. Mater., 28(2021), No. 6, pp. 899-914. https://doi.org/10.1007/s12613-020-2228-4

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Invited review

Recovery and separation of rare earth elements by molten salt electrolysis

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Corresponding authors:
Yun Xue E-mail: xueyun@hrbeu.edu.cn

Yong-de Yan E-mail: y5d2006@hrbeu.edu.cn
Received: 6 June 2020; Revised: 18 November 2020; Accepted: 19 November 2020; Available online: 26 November 2020

Abstract

Abstract

With the increasing demand of rare earth metals in functional materials, recovery of rare earth elements (REEs) from secondary resources has become important for the green economy transition. Molten salt electrolysis has the advantages of low water consumption and low hazardous waste during REE recovery. This review systematically summarizes the separation and electroextraction of REEs on various reactive electrodes in different molten salts. It also highlights the relationship between the formed alloy phases and electrodeposition parameters, including applied potential, current, and ion concentration. Moreover, the feasibility of using LiF–NaF–KF electrolyte to recover REEs is evaluated through thermodynamic analysis. Problems related to REE separation/recovery the choice of electrolyte are discussed in detail to realize the low-energy and high current efficiency of practical applications.
- rare earth element;
- molten salt;
- reactive electrode;
- electrochemical separation

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