Chen Xue, Wang Chenyang, Li Mao, Zhang Dexiu, Wei Yinmao
Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of Ministry of Education, College of Chemistry & Materials Science, Northwest University, Xi'an , 710069, China.
Mikrochim Acta. 2025 Apr 17;192(5):304. doi: 10.1007/s00604-025-07162-5.
Developing adsorbents capable of extracting rare earth element (REE) in harsh acidic solution is a challenging issue in the recycle of REE from secondary resources. In this work, porous polystyrene resin was facile modified with tris(2-aminoethyl)amine followed by methylenebis(phosphonic dichloride) to create a polydentate phosphonate-functionalized adsorbent for this purpose. The adsorption properties of four REE ions (Ce, Nd, Gd, and Dy) were investigated in terms of affinity constants, selectivity, and recovery. The adsorption mechanism of adsorbent for REE ions is regarded as the strong chelation interaction provided by the phosphonate ligand, which was verified by the experiments of acid and salt effects, thermodynamic and kinetic analysis. By using the diluted digest solution of a permanent magnet as model of strong acidic sample (1 mol/L HCl), the batch adsorption method generates high recovery ranging from 58.1 to 100% toward five REE ions (Y, Ce, Nd, Gd, and Dy), while the simulated continuous column bed enhances their total contents from 35.4% in the original digest solution to 88.9% in the eluent. In conclusion, the adsorbent indicates an excellent extraction ability in harsh acidic solution, and the recycle of REE using this adsorbent can predictably reduce alkali consumption to neutralize digest solution of secondary resources and improve greenness in manufacture.
开发能够在强酸性溶液中萃取稀土元素（REE）的吸附剂是从二次资源中回收REE面临的一个具有挑战性的问题。在这项工作中，多孔聚苯乙烯树脂先用三（2-氨基乙基）胺进行简便改性，然后用亚甲基双（膦酰二氯）处理，以制备用于此目的的多齿膦酸酯官能化吸附剂。从亲和常数、选择性和回收率方面研究了四种REE离子（Ce、Nd、Gd和Dy）的吸附性能。吸附剂对REE离子的吸附机制被认为是膦酸酯配体提供的强螯合相互作用，这通过酸和盐效应实验、热力学和动力学分析得到了验证。以永磁体的稀释消化液作为强酸性样品（1 mol/L HCl）的模型，采用分批吸附法对五种REE离子（Y、Ce、Nd、Gd和Dy）的回收率高达58.1%至100%，而模拟连续柱床将它们在原始消化液中的总含量从35.4%提高到洗脱液中的88.9%。总之，该吸附剂在强酸性溶液中表现出优异的萃取能力，使用这种吸附剂回收REE可以预期减少用于中和二次资源消化液的碱消耗，并提高制造过程的绿色度。
