School of Environmental & Safety Engineering, Changzhou University, Changzhou, PR China.
School of Chemistry & Chemical Engineering, Jiangsu University, Zhenjiang, PR China.
J Hazard Mater. 2018 Jul 5;353:496-504. doi: 10.1016/j.jhazmat.2018.04.022. Epub 2018 Apr 13.
Rare earth elements (REEs) are critical materials to many cutting-edge technologies but are difficult to separate from one another because of their chemical similarity. We present ionic imprinted mesoporous bilayer films (IIBFs) as an ideal adsorbent for selective separation of neodymium (Nd) and dysprosium (Dy) from sintered neodymium magnets. IIBFs were prepared according to dual-template docking oriented ionic imprinting (DTD-OII). Due to different imprinted compositions of bilayer films, IIBFs exhibited high specific surface area, fast binding equilibrium, and Janus properties for simultaneous selective adsorption of different rare earth ions, which made our imprinted bilayer mesoporous films a specialized adsorbent for adsorption of Nd(III) and Dy(III) at the same time. The adsorption capacities of optimized IIBFs were 17.50 mg g for Dy(III) and 12.15 mg g for Nd(III) at pH = 4.0. Moreover, we grafted thermo-responsive polymer on the one surface of IIBFs to realize controlled release of Nd(III) and Dy(III) by temperature. IIBFs demonstrate a high degree of reusability by cycling experiments by DTD-OII, which develop their promising applications for the REE recycling and separation industry.
稀土元素 (REEs) 是许多前沿技术的关键材料，但由于它们的化学相似性，彼此难以分离。我们提出了离子印迹介孔双层膜 (IIBF)，作为从烧结钕磁铁中选择性分离钕 (Nd) 和镝 (Dy) 的理想吸附剂。IIBF 是根据双模板对接定向离子印迹 (DTD-OII) 制备的。由于双层膜的印迹组成不同，IIBF 表现出高比表面积、快速结合平衡和 Janus 特性，可同时选择性吸附不同的稀土离子，这使得我们的印迹双层介孔膜成为同时吸附 Nd(III) 和 Dy(III) 的专用吸附剂。优化后的 IIBF 在 pH=4.0 时对 Dy(III) 的吸附容量为 17.50mg/g，对 Nd(III) 的吸附容量为 12.15mg/g。此外，我们在 IIBF 的一个表面接枝了温敏聚合物，通过温度实现了 Nd(III) 和 Dy(III) 的控制释放。通过 DTD-OII 的循环实验，IIBF 表现出了很高的可重复使用性，这为 REE 的回收和分离行业的发展提供了广阔的应用前景。
