Crystal structure of goethite

Neue Publikationen mit Blick auf kritische Metalle

Einige der technologisch wichtigen Metalle sind selten und gelten als kritisch. Diese beiden neuen Publikationen beschäftigen sich mit den thermodynamischen Eigenschaften von Fe-Oxiden, Sulfaten und Arsenaten, die kritische Metalle in ihrer Struktur aufnehmen können. Anhand dieser thermodynamischen Eigenschaften konnte die Gewinnung der Metalle aus natürlichen Materialien oder Abfallprodukten optimiert werden.
Crystal structure of goethite
Foto: Prof. Dr. Juraj Majzlan

New publications on the thermodynamic properties of Fe oxides, sulfates and arsenates

Some of the technologically important metals are also rare in the nature and considered as critical from the point of their accessibility and resources. In our work, we were interested in thermodynamic properties of Fe oxides, sulfates, and arsenates that take up some of the critical metals (indium, gallium, scandium) in their structures. Using these thermodynamic properties, extraction of the metals from natural materials (lateritic profiles) or waste products (red mud from processing of bauxite) could be optimized. We found that in all systems studied, critical metals strongly partition into the aqueous solution whereas Fe prefers the solid phase. The thermodynamic prediction can be imprecise if adsorption of the metals onto the surfaces of the Fe oxides prevails, as suggested by some field studies. More information about our thermodynamic work can be found in two new publications at https://doi.org/10.1016/j.jct.2024.107308Externer Link and https://doi.org/10.1007/s00269-024-01298-1Externer Link.

Crystal structure of goethite

Foto: Prof. Dr. Juraj Majzlan