A feasibility study for the recovery of lithium from salt water with the protonated lithium titanium oxide ion-sieves was carried out in this work. Lithium ions (Li+) in LiTi2O4 having a similar ion density with H+ allow repeated exchanges and regeneration with high selectivity. By Li7 magic angle spinning solid-state magnetic resonance, it is apparent that chemical structure of lithium in the ion-sieves is not perturbed during the repeated Li+/H+ exchange processes. As the dissolution of titanium is negligible (< 0.1%), the secondary contamination during the capture process can be minimized. The ion-sieves exhibit lithium capture capacities of up to 9.5 mg/g during the repeated Li+/H+ exchanges with H0.23Li0.77Ti2O4/LiTi2O4 for 24 h, and the captured Li+ may be recovered in the form of Li2CO3. Accordingly, the lithium capture method developed in this work could be integrated with current desalination processes for valuable lithium recovery.
All Science Journal Classification (ASJC) codes
- Aquatic Science