| About this Abstract |
| Meeting |
2025 TMS Annual Meeting & Exhibition
|
| Symposium
|
Aluminum Reduction Technology
|
| Presentation Title |
Theoretical Basis for Future Control of Impurity Elements in Hall-Héroult Cells |
| Author(s) |
Asbjorn Solheim, Ole S Kjos, Sverre Rolseth, Egil Skybakmoen |
| On-Site Speaker (Planned) |
Asbjorn Solheim |
| Abstract Scope |
The theory for behaviour of impurity elements in aluminium electrolysis cells is reviewed, with emphasis on the difference between noble and non-noble elements. Noble elements are transferred from bath to metal by diffusion and reaction at the metal-bath interface, while non-noble elements in bath and metal are at equilibrium. A general expression for the co-variation between the concentration of sodium and other trace elements in the produced metal was derived. While non-noble elements can be removed by oxidation, this is not possible with noble elements. Noble impurities is expected to become an increasing challenge in the future due to increasing concentrations in the raw materials and increasing ratio between recycled metal (alloys) and primary metal. Therefore, new methods are needed for removal of noble impurities, such as removing the fine fraction from the alumina and introduction of electrolytic separation of aluminium and noble elements in scrap. |
| Proceedings Inclusion? |
Planned: Light Metals |
| Keywords |
Aluminum, Other, Other |