Recovery of rare-earth elements from neodymium magnets using molten salt electrolysis

SPECIAL FEATURE: ORIGINAL ARTICLE 3rd 3R International Scientific Conference (3rd 3RINCs 2016)
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Abstract

Rare-earth elements are used in neodymium magnets, and these elements are critical to Japanese industry. In this study, we focused on the electrochemical behavior of neodymium magnets for the recovery of rare-earth elements using molten salt electrolysis. The influence of the rare-earth elemental composition of the neodymium magnets on their anodic polarization behavior and oxidation mechanism was studied. The use of potentiostatic electrolysis enabled selective leaching of rare-earth elements from neodymium magnets in the potential range from −1.8 to −0.8 V. The oxidation potential limits the oxidation stage, enabling rare-earth elements to be leached from mixed neodymium magnets simultaneously.

Keywords

Rare-earth elements Neodymium magnet Electrochemistry Molten salt 
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Notes

Acknowledgements

This work was supported by the Environment Research and Technology Development Fund of the Ministry of the Environment, Japan 3K143005, JSPS KAKENHI Grant No. 24656457, Japan Oil, Gas and Metals National Corporation, the Hori Sciences and Arts Foundation, and the Tokai Foundation for Technology.

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Copyright information

© Springer Japan 2016

Authors and Affiliations

  1. 1.Green Mobility Research Institute, Institutes of Innovation for Future SocietyNagoya UniversityNagoyaJapan
  2. 2.Graduated School of EngineeringNagoya UniversityNagoyaJapan
  3. 3.Institute of Materials and Systems for SustainabilityNagoya UniversityNagoyaJapan

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