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Rare metals preparation by electro-reduction of solid compounds in high-temperature molten salts

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Abstract

Direct electro-reduction of solid compounds in molten salts is a simple and straightforward electrolytic metallurgical method, which outperforms traditional pyrometallurgical methods such as carbothermic and metallothermic reductions in terms of economic viability, energy efficiency and carbon footprint. To better highlight the features of the direct electro-reduction of solid compounds in molten salts in extraction of rare metals, the scope of this paper is focused on the know-how of the cathodic process of the direct electro-reduction of solid compounds in molten salts in extraction of rare refractory metals including Ti, Zr, Hf, V, Nb, Ta, Mo and W, and rare disperse metals including Ga and Ge. In line with an introduction of the basic concept of the method, the characteristics of reaction paths in different systems are summarized and the corresponding strategy on tailoring energy efficiency and microstructure of electrolytic products are rationalized. The economic competence of the method might be enhanced by extending the method to controllable production of rare metals with high added values, well-defined microstructure and intriguing functionality.

Graphical Abstract

Direct electro-reduction of solid compounds in high-temperature molten salts emerges as an affordable, green, and controllable preparation of rare metals, in which, reaction paths show a significant influence on energy efficiency, composition/microstructure of electrolytic products and the economic competence of the process.

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Acknowledgments

This project was financially supported by the National Natural Science Foundation of China (Nos. 51325102 and 21203141), the Natural Science Foundation of Ningxia (No. NZ14001), the West Light Foundation of The Chinese Academy of Sciences and the Young-Talent Chenguang Project of Wuhan City.

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  1. School of Resource and Environmental Sciences, Hubei International Scientific and Technological Cooperation Base of Sustainable Resource and Energy, Wuhan University, Wuhan, 430072, China

    Wei Xiao & Di-Hua Wang

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  1. Wei Xiao
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Correspondence to Di-Hua Wang.

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Xiao, W., Wang, DH. Rare metals preparation by electro-reduction of solid compounds in high-temperature molten salts. Rare Met. 35, 581–590 (2016). https://doi.org/10.1007/s12598-016-0778-4

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  • DOI: https://doi.org/10.1007/s12598-016-0778-4

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