Abstract
Electrolytic production of metallic neodymium is carried out in fused fluoride salts containing neodymium oxide. Two major challenges pertaining to neodymium production are (a) low oxide solubility, (b) possibility of anodic fluorine gas evolution if the electrolysis rate exceeds feeding rate of neodymium oxide. In this study, a novel method is proposed in which iron fluoride (FeF3) is used as a fluorinating agent to convert neodymium oxide into neodymium fluoride. Electron Probe Micro Analysis (EPMA) results of as-converted salt show a complete conversion of neodymium oxide into neodymium fluoride. In the electrolysis process, iron is used as a reactive anode with electrochemical dissolution of iron into the melt, thus preventing fluorine gas evolution at the anode. Therefore, the fluorinating agent is constantly regenerated in situ which enables the continuous conversion of neodymium oxide feed. The cathodic product is a Nd–Fe alloy which can be directly used as a master alloy for the production of NdFeB permanent magnets.
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Acknowledgements
This research has received funding from the European Community’s Seventh Framework Programme ([FP7/2007-2013]) under grant agreement no. 607411 (MC-ITN EREAN: European Rare Earth Magnet Recycling Network, Project website: www.erean.eu). This publication reflects only the authors’ view, exempting the Community from any liability.
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Abbasalizadeh, A., Seetharaman, S., Venkatesan, P., Sietsma, J., Yang, Y. (2017). Novel Reactive Anode for Electrochemical Extraction of Rare Earth Metals from Rare Earth Oxides. In: Kim, H., Alam, S., Neelameggham, N., Oosterhof, H., Ouchi, T., Guan, X. (eds) Rare Metal Technology 2017. The Minerals, Metals & Materials Series. Springer, Cham. https://doi.org/10.1007/978-3-319-51085-9_9
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DOI: https://doi.org/10.1007/978-3-319-51085-9_9
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