Preparation, Characterization, and Adsorption Performance of H2TiO3 Lithium Ion Sieves with Homogeneous Nanoparticles: Kinetics, Thermodynamics, and Mechanism Analysis

Abstract Li 2 TiO 3 precursor with layered structure is successfully prepared by template‐free method using anatase TiO 2 and Li 2 CO 3 , followed by the treatment of dilute hydrochloric acid, which leads to obtaining H 2 TiO 3 lithium ion sieve nanoparticles with uniform dispersion and small size. The adsorption performance and mechanism of the H 2 TiO 3 are being studied. The experimental results show that the H 2 TiO 3 lithium ion sieve has a large BET specific surface area (19.10 m 2 g −1 ) and good thermal stability. At the same time, it also has a high adsorption rate and adsorption capacity (55.13 mg g −1 ) towards Li + in solution due to its high dispersibility and uniformity of particle size, which can expose more adsorption sites in LiCl solution. The adsorption capacity of the H 2 TiO 3 lithium ion sieve can reach 46.63 mg g −1 , which achieves 84.58% of the equilibrium adsorption capacity. The equilibrium adsorption parameters follow the Langmuir model perfectly, demonstrating that Li + undergoes monolayer adsorption. The results of thermodynamic and kinetic analysis show that the adsorption behavior of H 2 TiO 3 is spontaneous and conforms to the pseudo‐second‐order kinetic model, indicating the adsorption process is controlled by chemosorption. In addition, after five adsorption/desorption cycles, the H 2 TiO 3 lithium ion sieve still shows a high adsorption capacity of 46.15 mg g −1 , and the dissolution loss of titanium is only 0.14%, which shows that the cycle stability is excellent. XPS and zeta potential analyses illustrate that the adsorption mechanism of Li + on the H 2 TiO 3 is an ion exchange reaction between Li + and H + , combined with the electrostatic attraction of the adsorbent surface. Additionally, the adsorption performance of H 2 TiO 3 lithium ion sieve in West Taijinaier Salt Lake brine was tested, and the adsorbent material proves itself is a perspective candidate for lithium extraction from aqueous lithium resources.