Synthesis of Li+ adsorbent (H2TiO3) and its adsorption properties

H2TiO3 was obtained from the acid-modified adsorbent precursor Li2TiO3, which was synthesized by a solid-phase reaction between TiO2 and Li2CO3. The extraction ratio of Li+ from Li2TiO3 was 98.86%, almost with no Ti4+ extracted. The effects of lithium titanium ratio, calcining temperature and time were investigated on the synthesis of Li2TiO3. Li2TiO3, H2TiO3 and the adsorbed Li+ adsorbent were characterized by XRD and SEM. The lithium adsorption properties were investigated by the adsorption kinetics and adsorption isotherm. The results indicate that H2TiO3 has an excellent adsorptive capacity for Li+. Two simplified kinetic models including the pseudo-first-order and pseudo-second-order equations were selected to follow the adsorption processes. The rate constants of adsorption for these kinetic models were calculated. The results show that the adsorption process can be described by the pseudo-second-order equation, and the process is proved to be a chemical adsorption. The adsorption process that H2TiO3 adsorbs Li+ in LiCl solution well fits the Langmuir equation with monolayer adsorption.