Design of selective collectors for extraction of valuable metals

Design of selective collectors for extraction of valuable metals by separation of target minerals from mine tailings.

This project aims at developing a resource efficient and environmentally friendly way to separate titanite and apatite in tailings, recover valuable metal ions, e.g. Rare Earth Elements (REE), from titanite and apatite in the tailings and at the same time use the titanite and apatite to produce titanium phosphate (TiP) ion-exchangers for purification and extraction of metal ions from aqueous solutions.

The tailings material to study is provided to us from the Aitik mine (Boliden AB).

It is important to know which Ti-, P- and REE-bearing minerals that are present and their respective amounts. Therefore, in the first part of the project, a methodology for mineralogical characterisation of mine tailings by different microscopy methods is developed.

The second part of the project involves separation of minerals in the tailings material from Aitik. Minerals have different surface geometry so by using a collector with two functional groups, selectivity may be induced by matching distances. Collectors with different distances between their functional groups will be synthesized in our lab from amino acids and will therefore be non-toxic.
The third part of the project involves finding a way to recover different Rare Earth Elements (REE) present in the tailings. Since all REE have very similar properties efficient and selective separation must be able to target the very small differences that still exist. Important properties are closely connected to the structure of a material so if we can gain a fundamental understanding of structure-property relationships for different REE ligand systems, with a combination of molecular scale experimental and ab-initio computational methods we can predict and design suitable recovery processes and functional ligands.

The fourth part of the project is about synthesising cheap and efficient titanium phosphate (TiP) ion-exchange sorbents for extracting metal ions from aqueous solution. Amorphous TiP sorbents are known to efficiently sorb (heavy) metal ions from aqueous solutions through ion-exchange, even at trace levels, and can be synthesized from titanite and phosphoric acid (which can be made from apatite).

High risk project CAMM2
Project leader Anna-Carin Larsson
Participants Anuttam Patra, Christina Wanhainen, Mylene Trublet, Vasantha Gowda and Oleg Antzutkin.