Abstract
At KIGAM, the pilot plants have been developed and demonstrated two processes for recycling NdFeB waste magnets and manufacturing scraps. The former process uses thermal oxidation as a pretreatment before. The latter does caustic digestion and the thermal oxidation process. About 35% of the iron in feed was co-leached with REEs upon leaching of thermally oxidized products. Therefore, the separation process of REEs and non-REEs was carried out using the double-salt precipitation method to produce a high purity REEs solution applicable for solvent extraction. Instead, the leaching yield of iron upon leaching of caustic digestion and thermal oxidation products showed a value of 0.01%. Thus, the high purity REEs solution was obtained and directly applied to solvent extraction. Finally, REEs compounds of 99.9% or above could be obtained by solvent extraction using mixer settler and precipitation from raffinate and strip** solutions.
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Acknowledgements
The research was supported by the Energy Resource Technology Develo** Project of Korea Institute of Energy Technology Evaluation and Planning (KETEP) grant funded by Ministry of Trade, Industry, and Energy of Korea (MOTIE).
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Chung, K.W., Yoon, HS., Kim, CJ., Kim, R., Lim, B. (2022). KIGAM Technology for the Recovery of NdFeB Waste Magnet and Manufacturing Scraps. In: Lazou, A., Daehn, K., Fleuriault, C., Gökelma, M., Olivetti, E., Meskers, C. (eds) REWAS 2022: Develo** Tomorrow’s Technical Cycles (Volume I). The Minerals, Metals & Materials Series. Springer, Cham. https://doi.org/10.1007/978-3-030-92563-5_74
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DOI: https://doi.org/10.1007/978-3-030-92563-5_74
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