An integrated hydrometallurgical route for recycling SmCo magnets from production waste
- 1Department of Materials Engineering, Synthesis and Recycling (4MAT), Université Libre de Bruxelles Avenue FD Roosevelt 50, CP165/63 1050 Brussels Belgium [email protected].
- 2Department of Metallurgy, Faculté Polytechnique, Université de Lubumbashi Democratic Republic of Congo.
- 3Department of Metallurgical and Materials Engg., IIT Kharagpur Kharagpur WB 721302 India.
Abstract
Conventional hydrometallurgical processes for recycling waste SmCo magnets often require substantial reagent consumption and remain cost-intensive, particularly when solvent extraction is employed as a downstream separation step. In the present study, an integrated hydrometallurgical route was developed for the recovery of samarium, cobalt, and copper from SmCo magnet production scrap. More than 99% of samarium, cobalt and iron from the SmCo magnet scrap were leached with sulfuric acid, whereas copper remained in the leaching residue. Samarium was subsequently recovered selectively from the leachate as a high-purity sodium-samarium double sulfate using sodium sulfate as the precipitating agent. Importantly, we developed a selective iron removal step as an integral part of the flowsheet wherein the Fe(ii) present in the solution was oxidized to Fe(iii) using MnO₂, followed by selective precipitation of Fe(iii), aided by MnO. The resulting purified solution, enriched in cobalt and manganese, is suitable for electrowinning wherein cathodic cobalt formation can be simultaneously accompanied with anodic MnO₂ deposition. Overall, the integrated hydrometallurgical process developed in this study is facile, scalable and suitable for recycling complex SmCo magnet production scrap with high iron impurity.
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BibTeX
@article{heritier2026integrated,
title = {{An integrated hydrometallurgical route for recycling SmCo magnets from production waste}},
author = {Tshipeshi Makina Héritier and Muthukumar Volga and Arundhati Jena and Chenna Rao Borra and Mwema Mutamba Edouard and Prakash Venkatesan},
journal = {RSC advances},
year = {2026},
month = nov,
doi = {10.1039/d6ra08919d},
url = {https://europepmc.org/article/PMC/PMC13725791},
note = {CC BY-NC},
}
RIS
TY - JOUR
TI - An integrated hydrometallurgical route for recycling SmCo magnets from production waste
AU - Tshipeshi Makina Héritier
AU - Muthukumar Volga
AU - Arundhati Jena
AU - Chenna Rao Borra
AU - Mwema Mutamba Edouard
AU - Prakash Venkatesan
PY - 2026
DA - 2026/11/02
JO - RSC advances
DO - 10.1039/d6ra08919d
UR - https://europepmc.org/article/PMC/PMC13725791
AB - Conventional hydrometallurgical processes for recycling waste SmCo magnets often require substantial reagent consumption and remain cost-intensive, particularly when solvent extraction is employed as a downstream separation step. In the present study, an integrated hydrometallurgical route was developed for the recovery of samarium, cobalt, and copper from SmCo magnet production scrap. More than 99% of samarium, cobalt and iron from the SmCo magnet scrap were leached with sulfuric acid, whereas copper remained in the leaching residue. Samarium was subsequently recovered selectively from the leachate as a high-purity sodium-samarium double sulfate using sodium sulfate as the precipitating agent. Importantly, we developed a selective iron removal step as an integral part of the flowsheet wherein the Fe(ii) present in the solution was oxidized to Fe(iii) using MnO₂, followed by selective precipitation of Fe(iii), aided by MnO. The resulting purified solution, enriched in cobalt and manganese, is suitable for electrowinning wherein cathodic cobalt formation can be simultaneously accompanied with anodic MnO₂ deposition. Overall, the integrated hydrometallurgical process developed in this study is facile, scalable and suitable for recycling complex SmCo magnet production scrap with high iron impurity.
SN - 2046-2069
ER -