CMI researchers at Colorado School of Mines conducted the research for this highlight
Innovation
- Inert roasting was used as a selective desulfurization step to upgrade cobaltiferous pyrite, where Co is structurally hosted within the pyrite lattice.
- The treatment increased cobalt (Co) grades through sulfur removal while transforming the sulfide matrix into a calcine for downstream magnetic separation.
Achievement
- Inert roasting increased cobalt grades by up to 15% with negligible cobalt loss and high-purity sulfur co-production.
- Magnetic separation of the roasted calcine yielded a concentrate with 2.09% Co at 82.5% recovery, a 16-74% improvement over prior baselines.
Significance and Impact
- Publication describes a pathway to upgrade cobaltiferous pyrite feedstocks beyond conventional flotation limits.
- Supports improved Co recovery from complex domestic sulfide resources.
Hub Target Addressed
Recovering critical materials from unconventional sources.
