Recovery and separation of gallium, germanium from zinc wastes

Fig. 1: Mineral composition of Tristate tailings. High correlation values were observed between Ga/Ge and Zn concentrations across different size fractions.
Fig. 1: Mineral composition of Tristate tailings. High correlation values were observed between Ga/Ge and Zn concentrations across different size fractions.

CMI researchers from Missouri S&T conducted the activity for this highlight

Innovation
Flowsheet development for selective separation of Ga and Ge from unconventional sources (zinc wastes) of different sources.

Achievement

  • Demonstrated that hemimorphite (Zn silicates) and sphalerite (Zn sulfide) are the major carriers of Ga and Ge in Tristate tailing. Highest concentrations detected in grains < 45 μm. 
  • Demonstrated that Ga can be selectively extracted in a sulfate matrix using oxime-based ligands.

Significance and Impact

  • Potential increase Ga & Ge domestic production.
  • Supply chain diversification. 
  • Robust flowsheets guided by density functional theory (DFT) and ab initio molecular dynamic (AIMD) simulation studies.

Hub Target Addressed
Semiconductors - Capturing gallium and germanium from domestic zinc residues.

Fig. 2: Change in distribution ration vs. pH for Ga, Zn, Fe, and Indium (In) in an oxime/sulfate system. 
Fig. 2: Change in distribution ration vs. pH for Ga, Zn, Fe, and Indium (In) in an oxime/sulfate system.