Su Xiang, Wang Yanliang, Guo Xiangguang, Dong Yamin, Gao Yun, Sun Xiaoqi
CAS Key Laboratory of Design and Assembly of Functional Nanostructures, and Fujian Key Laboratory of Nanomaterials, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002, PR China; University of Chinese Academy of Sciences, Beijing 100039, PR China.
CAS Key Laboratory of Design and Assembly of Functional Nanostructures, and Fujian Key Laboratory of Nanomaterials, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002, PR China.
Waste Manag. 2018 Aug;78:992-1000. doi: 10.1016/j.wasman.2018.07.004. Epub 2018 Jul 17.
Recovery of secondary resources including waste SmCo magnets contributes to easing the natural resources and environmental issues. For the development of recovery technologies, an ionic liquid (IL)-based precipitation route based on [trihexyl(tetradecyl)phosphonium][benzene-1,4-dioxydiacetate] ([P][BDOAC]) is presented. The slow release of [BDOAC] from [P][BDOAC] increases the kinetics difference in the formations of precipitates, and makes the precipitates contain less impurity. While cobalt-rich solution is obtained with no loss, precipitation efficiency of Sm(III) and Cu(II) reaches 96.8% and 100% respectively. Afterwards, Cu(II) is removed using aqueous ammonia and pure Cu(II) (96.4% precipitation efficiency) is obtained by adjusting the pH of cuprammonium complex solution. The proposed process without volatile diluent reveals higher separation factors of Sm/Co, Cu/Co and Sm/Cu. Lower acidities are efficient for the complete stripping of Sm(III) and Cu(II) from their precipitates. SmCl and CuCl solutions are obtained both with the high purities. Moreover, the IL-based precipitant can be regenerative. It is shown that the strategy is efficient for recovering and separating Sm, Co and Cu from the simulated leaching solution of waste SmCo magnets.
包括废钐钴磁体在内的二次资源回收有助于缓解自然资源和环境问题。为了开发回收技术，提出了一种基于[三己基（十四烷基）鏻][苯-1,4-二氧二乙酸酯]（[P][BDOAC]）的离子液体（IL）沉淀路线。[BDOAC]从[P][BDOAC]中的缓慢释放增加了沉淀物形成过程中的动力学差异，并使沉淀物含有更少的杂质。在无损失地获得富钴溶液的同时，Sm(III)和Cu(II)的沉淀效率分别达到96.8%和100%。之后，使用氨水去除Cu(II)，通过调节铜氨络合溶液的pH值获得纯Cu(II)（沉淀效率96.4%）。所提出的无挥发性稀释剂的工艺显示出更高的Sm/Co、Cu/Co和Sm/Cu分离因子。较低的酸度对于从沉淀物中完全反萃Sm(III)和Cu(II)是有效的。均获得了高纯度的SmCl和CuCl溶液。此外，基于IL的沉淀剂可以再生。结果表明，该策略对于从废钐钴磁体的模拟浸出液中回收和分离Sm、Co和Cu是有效的。
