Lithium recovery with LiTi₂O₄ ion-sieves

Area of Science:

• Materials Science
• Chemical Engineering
• Environmental Science

Background:

• Lithium recovery from natural water sources is crucial for sustainable energy.
• Developing selective and efficient ion-sieves is key for lithium extraction.
• Existing methods face challenges with selectivity and regeneration.

Purpose of the Study:

• To investigate the feasibility of using protonated lithium titanium oxide ion-sieves for lithium recovery from saltwater.
• To evaluate the stability and reusability of the ion-sieves.
• To assess the potential for integrating this method with desalination.

Main Methods:

• Utilized protonated lithium titanium oxide (LiTi2O4) as an ion-sieve material.
• Performed repeated lithium ion (Li+) / proton (H+) exchange experiments.
• Analyzed material stability using Li-7 magic angle spinning solid-state magnetic resonance.
• Quantified lithium capture capacity and titanium dissolution.

Main Results:

• Achieved lithium capture capacities up to 9.5 mg/g through repeated Li+/H+ exchanges.
• Confirmed structural integrity of lithium within the ion-sieves after multiple cycles.
• Demonstrated negligible titanium dissolution (<0.1%), minimizing secondary contamination.
• Recovered captured lithium in the form of lithium carbonate (Li2CO3).

Conclusions:

• Protonated lithium titanium oxide ion-sieves offer a stable and selective method for lithium recovery from saltwater.
• The developed process minimizes contamination and allows for efficient lithium capture and recovery.
• This technology holds promise for integration with existing desalination plants for co-production of lithium and freshwater.