Li Xiaohua, Binnemans Koen
KU Leuven, Department of Chemistry, Celestijnenlaan 200F, P.O. Box 2404, B-3001 Leuven, Belgium.
Chem Rev. 2021 Apr 28;121(8):4506-4530. doi: 10.1021/acs.chemrev.0c00917. Epub 2021 Mar 16.
Dissolution of metals in organic solvents is relevant to various application fields, such as metal extraction from ores or secondary resources, surface etching or polishing of metals, direct synthesis of organometallic compounds, and separation of metals from other compounds. Organic solvents for dissolution of metals can offer a solution when aqueous systems fail, such as separation of metals from metal oxides, because both the metal and metal oxide could codissolve in aqueous acidic solutions. 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 oxidizing agents, chelating agents, and solvents. Different oxidizing agents for dissolution of metals are reviewed such as halogens, halogenated organics, donor-acceptor electron-transfer systems, polyhalide ionic liquids, and others. Both chemical and electrochemical processes are included. The review can guide researchers to develop more efficient, economic, and environmentally friendly processes for dissolution of metals in their elemental state.
金属在有机溶剂中的溶解与各种应用领域相关，例如从矿石或二次资源中提取金属、金属的表面蚀刻或抛光、有机金属化合物的直接合成以及从其他化合物中分离金属。当水体系无法实现时，用于溶解金属的有机溶剂可以提供一种解决方案，例如从金属氧化物中分离金属，因为金属和金属氧化物都可能在酸性水溶液中共溶。本文综述批判性地讨论了在不同应用领域中用于金属氧化溶解的有机介质（传统分子有机溶剂、离子液体、低共熔溶剂和超临界二氧化碳）。讨论了各种浸出剂体系（通常由氧化剂、螯合剂和溶剂组成）溶解过程的反应机理。综述了用于溶解金属的不同氧化剂，如卤素、卤代有机物、供体-受体电子转移体系、多卤化物离子液体等。其中包括化学和电化学过程。该综述可以指导研究人员开发更高效、经济和环境友好的方法来溶解单质态的金属。
