Deep eutectic solvents for separation and purification applications in critical metal metallurgy: Recent advances and perspectives

Shuo Chen; Shengpeng Su; Yanfang Huang; Bingbing Liu; Hu Sun; Shuzhen Yang; Guihong Han

doi:10.1007/s12613-024-2923-7

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Shuo Chen, Shengpeng Su, Yanfang Huang, Bingbing Liu, Hu Sun, Shuzhen Yang, and Guihong Han, Deep eutectic solvents for separation and purification applications in critical metal metallurgy: Recent advances and perspectives, Int. J. Miner. Metall. Mater.,(2025). https://doi.org/10.1007/s12613-024-2923-7

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Shuo Chen, Shengpeng Su, Yanfang Huang, Bingbing Liu, Hu Sun, Shuzhen Yang, and Guihong Han, Deep eutectic solvents for separation and purification applications in critical metal metallurgy: Recent advances and perspectives, Int. J. Miner. Metall. Mater.,(2025). https://doi.org/10.1007/s12613-024-2923-7

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Review

Deep eutectic solvents for separation and purification applications in critical metal metallurgy: Recent advances and perspectives

+ Author Affiliations

Corresponding author:
Guihong Han E-mail: hanguihong@zzu.edu.cn
Received: 1 November 2023; Revised: 16 April 2024; Accepted: 18 April 2024; Available online: 19 April 2024

Abstract

Abstract

Solvent extraction, a separation and purification technology, is crucial in critical metal metallurgy. Organic solvents commonly used in solvent extraction exhibit disadvantages, such as high volatility, high toxicity, and flammability, causing a spectrum of hazards to human health and environmental safety. Neoteric solvents have been recognized as potential alternatives to these harmful organic solvents. In the past two decades, several neoteric solvents have been proposed, including ionic liquids (ILs) and deep eutectic solvents (DESs). DESs have gradually become the focus of green solvents owing to several advantages, namely, low toxicity, degradability, and low cost. In this critical review, their classification, formation mechanisms, preparation methods, characterization technologies, and special physicochemical properties based on the most recent advancements in research have been systematically described. Subsequently, the major separation and purification applications of DESs in critical metal metallurgy were comprehensively summarized. Finally, future opportunities and challenges of DESs were explored in the current research area. In conclusion, this review provides valuable insights for improving our overall understanding of DESs, and it holds important potential for expanding separation and purification applications in critical metal metallurgy.
- deep eutectic solvents;
- preparations;
- properties;
- separation and purification;
- critical metal metallurgy

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