Simple, cheap sorbent opens door for lithium recovery

diagram of Environmental impact assessment of Li2SO4 production via CMI aluminum hydroxide sorbent cycle vs standard Li2CO3 production by evaporation and precipitation. Feed for both methods is a leachate obtained from domestic mine tailings.
Environmental impact assessment of Li2SO4 production via CMI aluminum hydroxide sorbent cycle vs standard Li2CO3 production by evaporation and precipitation. Feed for both methods is a leachate obtained from domestic mine tailings.

CMI researchers from Oak Ridge National Laboratory and Arizona State University conducted the research for this highlight.

Achievement
High lithium sorption capacity of 5.5 meq/g in >86% extraction from a sulfate leachate of domestic mine tailings achieved with amorphous aluminum hydroxide.

Significance and impact

  • Avoids new mining and pre-evaporation of leachate.
  • Sorbent loads Li fast and selectively, releases Li in water, and is reusable, follows circular-economy model. 
  • Life-cycle analysis predicts significant environmental advantage of this system compared to that of conventional evaporation-precipitation process.
  • High-temperature solution calorimetry demonstrates the enthalpy stability order as gibbsite > bayerite > amorphous Al(OH)3, revealing advantage of the latter. 

Hub Targets Addressed
Unlocking unconventional resources. Highly selective separation from complex sources.