Leaching of rare earth elements from NdFeB magnets without mechanical pretreatment by sulfuric (H2SO4) and hydrochloric (HCl) acids

dc.contributorAalto-yliopistofi
dc.contributorAalto Universityen
dc.contributor.authorKlemettinen, Anna
dc.contributor.authorŻak, Andrzej
dc.contributor.authorChojnacka, Ida
dc.contributor.authorMatuska, Sabina
dc.contributor.authorLeśniewicz, Anna
dc.contributor.authorWełna, Maja
dc.contributor.authorAdamski, Zbigniew
dc.contributor.authorKlemettinen, Lassi
dc.contributor.authorRycerz, Leszek
dc.contributor.departmentDepartment of Chemical and Metallurgical Engineering
dc.contributor.departmentWrocław University of Science and Technology
dc.contributor.departmentMetallurgy (MTG)
dc.date.accessioned2021-12-31T13:57:17Z
dc.date.available2021-12-31T13:57:17Z
dc.date.issued2021-12
dc.descriptionFunding Information: Acknowledgments: Authors would like to thank the Wroclaw Research Center EIT+ for the financial support. The work was also co-financed by statutory activity subsidy from the Polish Ministry of Science and Higher Education for the Faculty of Chemistry of Wroclaw University of Science and Technology. Funding Information: This work was supported by Wroclaw Research Center EIT+ within the project ?The Application of Nanotechnology in Advanced Materials?NanoMat? (POIG 01.01.02-02-002/08). Publisher Copyright: © 2021 by the authors. Licensee MDPI, Basel, Switzerland.
dc.description.abstractA simplified approach for rare earth elements leaching from NdFeB (neodymium-iron-boron) magnets was investigated. The possibility of simplifying the magnet recycling process by excluding grinding, milling and oxidative roasting unit operations was studied. Attempts to skip the demagnetization step were also conducted by using whole, non-demagnetized magnets in the leaching process. The presented experiments were conducted to optimize the operating conditions with respect to the leaching agent and its concentration, leaching time, leaching temperature and the form of the feed material. The use of hydrochloric and sulfuric acids as the leaching agents allowed selective leaching of NdFeB magnets to be achieved while leaving nickel, which is covering the magnets, in a solid state. The application of higher leaching temperatures (40 and 60◦ C for sulfuric acid and 40◦ C for hydrochloric acid) allowed us to shorten the leaching times. When using broken demagnetized magnets as the feed material, the resulting rare earth ion concentrations in the obtained solutions were significantly higher compared to using whole, non-demagnetized magnets.en
dc.description.versionPeer revieweden
dc.format.extent18
dc.format.mimetypeapplication/pdf
dc.identifier.citationKlemettinen , A , Żak , A , Chojnacka , I , Matuska , S , Leśniewicz , A , Wełna , M , Adamski , Z , Klemettinen , L & Rycerz , L 2021 , ' Leaching of rare earth elements from NdFeB magnets without mechanical pretreatment by sulfuric (H 2 SO 4 ) and hydrochloric (HCl) acids ' , Minerals , vol. 11 , no. 12 , 1374 . https://doi.org/10.3390/min11121374en
dc.identifier.doi10.3390/min11121374
dc.identifier.issn2075-163X
dc.identifier.otherPURE UUID: 5f62cc08-24dd-46c2-b2a3-fd4a86efbd4c
dc.identifier.otherPURE ITEMURL: https://research.aalto.fi/en/publications/5f62cc08-24dd-46c2-b2a3-fd4a86efbd4c
dc.identifier.otherPURE LINK: http://www.scopus.com/inward/record.url?scp=85120606459&partnerID=8YFLogxK
dc.identifier.otherPURE FILEURL: https://research.aalto.fi/files/77128691/CHEM_Klemettinen_et_al_Leaching_of_rare_earth_elements_2021_Minerals.pdf
dc.identifier.urihttps://aaltodoc.aalto.fi/handle/123456789/111986
dc.identifier.urnURN:NBN:fi:aalto-2021123111126
dc.language.isoenen
dc.publisherMultidisciplinary Digital Publishing Institute (MDPI)
dc.relation.ispartofseriesMineralsen
dc.relation.ispartofseriesVolume 11, issue 12en
dc.rightsopenAccessen
dc.subject.keywordExtractive metallurgy
dc.subject.keywordRare earth elements
dc.subject.keywordRecycling
dc.subject.keywordUrban mining
dc.titleLeaching of rare earth elements from NdFeB magnets without mechanical pretreatment by sulfuric (H2SO4) and hydrochloric (HCl) acidsen
dc.typeA1 Alkuperäisartikkeli tieteellisessä aikakauslehdessäfi
dc.type.versionpublishedVersion
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