Moreno Katherine, Díaz Ximena, Endara Diana, Sánchez Fernando, Aragón-Tobar Carlos F
Department of Extractive Metallurgy, Escuela Politécnica Nacional, Ladrón de Guevara E11-253, P.O. Box 17-01-2759, Quito 170525, Ecuador.
Molecules. 2024 Aug 7;29(16):3742. doi: 10.3390/molecules29163742.
The traditional metallurgical routes for producing lead and zinc from primary sources have a significant environmental footprint. Thus, using less pollutant solvents, such as deep eutectic solvents (DESs), would offer a greener solution in metal extraction. This study explores the use of three DESs based on choline chloride (ChCl) (1:2 ChCl-urea, 1:2 ChCl-ethylene glycol, and 1:2 ChCl-glycerol) for recovering Zn and Pb from a sphalerite-galena concentrate of the mining region in Ecuador. Leaching tests of the concentrate (untreated and roasted at 600 °C) in each DES were conducted (30 °C-24 h). The effect of adding iodine as an oxidizing agent was also evaluated. Recoveries of 2% (Zn) and 14% (Pb) were reported when leaching the untreated concentrate with DES. These recovery values increased to 11% (Zn) and 99% (Pb) after adding iodine during the leaching of the untreated concentrate. Roasting had a similar effect on leaching, increasing the recovery values of Zn (75%) and Pb (90%). Combining roasting as a pretreatment and iodine as an oxidizing agent produced higher Zn recoveries (99%) and Pb (99%). These results were compared to recoveries in acid leaching (HSO and HNO), revealing the potential of DESs as an alternative for metal recovery from primary sources.
从原生矿源生产铅和锌的传统冶金路线对环境影响巨大。因此，使用污染性较小的溶剂，如低共熔溶剂（DESs），在金属提取过程中可提供更环保的解决方案。本研究探索了三种基于氯化胆碱（ChCl）的低共熔溶剂（1:2 ChCl - 尿素、1:2 ChCl - 乙二醇和1:2 ChCl - 甘油）用于从厄瓜多尔矿区的闪锌矿 - 方铅矿精矿中回收锌和铅。对精矿（未处理的和在600℃下焙烧的）在每种低共熔溶剂中进行浸出试验（30℃ - 24小时）。还评估了添加碘作为氧化剂的效果。用低共熔溶剂浸出未处理的精矿时，锌的回收率为2%，铅的回收率为14%。在未处理精矿浸出过程中添加碘后，这些回收率分别提高到11%（锌）和99%（铅）。焙烧对浸出有类似效果，提高了锌（75%）和铅（90%）的回收率。将焙烧作为预处理并结合碘作为氧化剂，锌和铅的回收率更高（锌99%，铅99%）。将这些结果与酸浸（硫酸和硝酸）的回收率进行比较，揭示了低共熔溶剂作为从原生矿源回收金属的替代方法的潜力。
