| Popis: |
Scandium (Sc) is one of the key elements in the green economy due to its use in fuel cells and as alloying metal for aluminium, but the scandium market is not working in the sense that very little is offered at a high price making it impossible to gain use of the metal. Scandium is a rare earth element (REE) and as such, it is not very rare, but the concentration of it is always low making it a challenge to produce scandium at low cost. Compared with the other REE, Sc3+ is a much smaller ion giving it properties closer to Al3+, Fe3+, and Zr4+. We therefore often do not find Sc together with the other REE, but instead in titanium-, aluminium-, and zirconium-containing minerals. Processes involving Sc separation are different from the usual REE processes. Exploitation of the mineral davidite is used as an example of small deposits, which may be utilized through efficient mining whereas other large operations like recovery from bauxite residues (red mud) are considered for comparison. |
