A1 Journal article (refereed), original research

One-step recovery of REE oxalates in electro-leaching of spent NdFeB magnets


Open Access publication

Publication Details
Authors: Makarova Irina, Ryl Jacek, Sun Zhi, Kurilo Irina, Górnicka Karolina, Laatikainen Markku, Repo Eveliina
Publisher: Elsevier
Publication year: 2020
Language: English
Related Journal or Series Information: Separation and Purification Technology
Volume number: 251
ISSN: 1383-5866
eISSN: 1873-3794
JUFO-Level of this publication: 2
Open Access: Open Access publication
Location of the parallel saved publication: http://urn.fi/URN:NBN:fi-fe2020092876070

Abstract

Recovery of rare-earth
elements (REEs) from spent NdFeB magnets is receiving great attention because
of high amount of neodymium and potential risk of environmental pollution. In
this study, a novel environment-friendly hydrometallurgical route is proposed
for efficient recovery of REEs during electrochemical leaching with sulfuric
and oxalic acids. With proper adjustment of the electrolyte composition and
operating conditions, effective separation of different elements is observed; a
compact layer of REE oxalates in a purity of up to 93% is obtained on the
cathode, while iron remains in the solution and as solid residue for further
recovery. The mechanisms during the electro-leaching process were subsequently
investigated and we propose that cathodic deposition of the REEs is due to
electrostatic attraction of the REE-oxalate particles on the cathode. With this
finding, selective recovery of REEs from spent magnets can be achieved. This study
provides a new insight on electronic waste recycling by implementing principles
of electrochemistry.


LUT Focus Areas

Last updated on 2020-02-10 at 09:32

Share link