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

Abstract Metatitanic acid (H 2 TiO 3 ) 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 ( q e ), 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. H 2 TiO 3 was highly stable and reusable; its highest q e (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.