Adsorptive Li+ mining from liquid resources by H2TiO3: Equilibrium, kinetics, thermodynamics, and mechanisms

Metatitanic acid (H2TiO3) is an emerging lithium ion sieve (LIS) that can potentially replace the well-known manganese-based LIS. Systematic adsorption studies on the effects of solution pH, solid/liquid ratio, temperature, and feed concentration were conducted. H+ accumulation critically limited the Li+ capacity (qe), but was circumvented under optimal conditions. Li+ adsorption was Langmuir-type and followed pseudo-second-order rate model; thermodynamic parameters reveal its feasibility, spontaneity, and endothermicity. H2TiO3 was highly stable and reusable; its highest qe (94.5 mg g−1) is superior over other known LIS. Li+ was effectively recovered from seawater, demonstrating its high industrial potential for aqueous Li+ mining.