Oxidative dissolution of metals in organic solvents: a critical review

Dissolution of metals in organic solvents is relevant to various applications, such as metal extraction from ores or secondary resources, surface etching, and separation of metals from other compounds. Organic solvents can offer a solution when aqueous systems fail. SOLVOMET/SIM² researchers have now published a critical review paper in the high-impact journal “Chemical Reviews” (IF = 52) on the oxidative dissolution of metals in such organic solvents.


Dissolution of metals in organic solvents is relevant to various application fields. Organic solvents for dissolution of metals can offer a solution when aqueous systems fail, such as separation of metals from metal oxides, because both metal and metal oxide could co-dissolve in aqueous acidic solutions.

Chemical Reviews

This review critically discusses organic media (conventional molecular organic solvents, ionic liquids, deep-eutectic solvents and supercritical carbon dioxide) for oxidative dissolution of metals in different application areas. The reaction mechanisms of dissolution processes are discussed for various lixiviant systems, which generally consist of oxidising agents, chelating agents and solvents.

The different types of organic leaching systems, together with the studied oxidative dissolution of metals in the corresponding systems, are summarised in Figure 1.

The aim of this review is to give an overview of the emerging research field of oxidative dissolution of metals in organic solvents. By highlighting the oxidation reaction mechanisms, this review can be helpful for the development of new efficient, environmentally-benign and economic processes for the dissolution of metals in their elemental state for various applications.

Figure 1. Overview of the organic leaching systems and the metals that have been studied for oxidative dissolution in the corresponding leaching systems.

Biography Sharron Li

Xiaohua Li started her postdoc research with Prof. Koen Binnemans at KU Leuven (SOLVOMET Group) from November 2016, after obtaining her doctor degree from university of Twente in the Netherlands. Since September 2019, she has been working on her FWO postdoctoral grant to develop new ionic liquid-based aqueous biphasic system for rare-earth metal recovery. Her main research interests include solvent extraction, oxidative dissolution of metals, metal recovery, aqueous biphasic system and ionic liquids.

Full reference paper

Li, X.; Binnemans, K. Oxidative Dissolution of Metals in Organic Solvents. Chem. Rev. 2021. https://doi.org/10.1021/acs.chemrev.0c00917

Acknowledgements

The research leading to these results received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 Research and Innovation Programme: Grant Agreement 694078—Solvometallurgy for critical metals (ERC SOLCRIMET). The research was also funded by a postdoctoral grant of the Research Foundation Flanders (FWO) to X. Li (12ZA520N).