Extraction of Co and Cu from high As legacy cobalt mine tailings

Electrochemical mediated leaching diagram of cobalt from legacy cobalt mine tailings provided by lixivia
Electrochemical mediated leaching diagram of cobalt from legacy cobalt mine tailings provided by Lixivia 

CMI researchers from Idaho National Laboratory conducted the research for this highlight.

Innovation 
Electrochemically mediated leaching of Co from legacy cobalt mine tailings with immobilization of As.

Achievement

  • 86% of Co and 87% of As were extracted from a legacy mine tailing containing 1.3% Co, 1.8% Cu, and 5.3% As.
  • Operation of the system for 36 hours allowed to isolate 67% of the leached Cu from the leachate to form Cu3As alloy at the cathode. 
  • Over 81% of the remaining As was immobilized as scorodite with a follow-up electrochemical processing.

Significance and Impact
Low-temperature recovery of Co from mine tailings and immobilization of As potentially opens an environmentally friendly pathway for domestic Co production.

Hub Target Addressed 
Unlocking unconventional resources.