This article has been reviewed according to Science X's editorial process and policies. Editors have highlighted the following attributes while ensuring the content's credibility:

fact-checked

trusted source

proofread

Researchers realize selective recovery of high-value rare earth elements from waste NdFeB

magnet
Credit: Unsplash/CC0 Public Domain

Recycling high-value rare earth elements from NdFeB waste can save resources, reduce industrial waste, protect the environment and bring considerable economic benefits. However, most traditional recovery methods take a long time to process, have high acid consumption, and low selectivity.

In a study published in Separation and Purification Technology, the research group led by Prof. Yang Fan from Fujian Institute of Research on the Structure of Matter of the Chinese Academy of Sciences proposed a new integrated method for recycling permanent magnet waste by betaine hydrochloride ([Hbet]Cl) solution extraction.

The researchers first carried out leaching experiments on fully roasted magnetic clay samples, and selected [Hbet]Cl as the leaching agent.

They found that when leaching temperature was 200° Celsius, leaching time was eight hours, lixiviant [Hbet]Cl concentration was 0.2 mol/L, and solid–liquid ratio was 1:150 g/ml. They were able to get optimum leaching results of 99.81% Pr, 97.05% Nd, 95.51% Gd, 56.24% Ce and 0.20% Fe, and almost all remained in the residue.

Compared with methods for common lixiviants, the results of the proposed method showed a better leaching rate and selectivity. And the leaching sequence was in line with established chemical properties.

In addition, the researchers revealed that the new lixiviant ([Hbet]Cl) will not reduce the extraction rate of rare earth materials by N, N-di-2-ethylhexyl diglycolamic acid (D2EHDGAA) extractant, and the extraction rate of D2EHDGAA for Nd in [Hbet]Cl solution is significantly improved.

More information: Chang Du et al, Recovery of high-value rare earth elements from waste NdFeB by the water-soluble ammonium salt [Hbet]cl, Separation and Purification Technology (2022). DOI: 10.1016/j.seppur.2022.122946

Citation: Researchers realize selective recovery of high-value rare earth elements from waste NdFeB (2023, February 20) retrieved 5 March 2024 from https://phys.org/news/2023-02-recovery-high-value-rare-earth-elements.html
This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.

Explore further

Mining precious rare-earth elements from coal fly ash with a reusable ionic liquid

14 shares

Feedback to editors