| About this Abstract |
| Meeting |
2024 TMS Annual Meeting & Exhibition
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| Symposium
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Scandium Extraction and Use in Aluminum Alloys
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| Presentation Title |
Behavior of Yttrium and Other Impurities in the Production of Scandium Oxide from Bauxite Residue |
| Author(s) |
Alexander Suss, Alexander Kozyrev, Natalia Kuznetsova, Alexander Damaskin, Sergey Pishchalniko, Andrey V. Panov, Sergey Ordon, Oleg Milshin |
| On-Site Speaker (Planned) |
Andrey V. Panov |
| Abstract Scope |
Bauxites in the North of European Russia are characterized by a high scandium content (up to 350 ppm calculated as Sc2O3). Most of scandium is imbedded into the structure of aluminum-containing minerals, as well as into zircon ZrSiO4 and apatite. These minerals break down during the pressure digestion of the bauxites, so scandium is re-precipitated and sorbed on the surface of bauxite residue particles. UC RUSAL has develop and pilot tested the extraction of scandium oxide from bauxite residue using a sodium bicarbonate solution that enables to dissolve up to 50 % of scandium into the solution followed by precipitation of the concentrate and purification to obtain 99.0 % Sc2O3. The extraction uses actual liquors from alumina production and flue gases. Bauxites contain a number of REM elements (e.g. zircon, titanium, hafnium, copper, yttrium, thorium, etc.). Chemical behaviour of said REMs during the sodium bicarbonate digestion is similar to the behaviour of scandium. To obtain pure scandium oxide (2N) (Sc2O3 ≥ 99.0 wt.%) without radioactive impurities effective purification technology was developed. Moreover, resulting mutual neutralisation of some streams allows obtaining a high-grade REM concentrate. The additional advantage of this process lies in reducing the carbon footprint of alumina production due to the use of flue gases containing up to 8 vol.% CO2, as well as alkali neutralisation in the bauxite residue. |
| Proceedings Inclusion? |
Planned: Light Metals |
| Keywords |
Other, |