Synthesis of doped titanium-based lithium adsorbents with excellent stability and adsorption performance by solid state reactions

Titanium-based lithium-ion sieves (LTO) are often employed for lithium recovery from solutions due to their high adsorption uptake. To further reduce the Ti dissolution loss rate and enhance the adsorption performance of LTO, metal-doping was conducted using solid-state reactions in this work, and the effects of incorporated metal elements and doping amounts were investigated. The results indicated that, the doping of 5 % tungsten (W), zirconium (Zr) or cerium (Ce) significantly reduces the titanium dissolution rate from 1.52 % (without doping) to 0.77 %, 1.1 %, and 1.17 % respectively, while the doping of iron (Fe) and molybdenum (Mo) increases the Ti dissolution rate. Simultaneously, the dissolution rates of W, Zr, and Ce (0.15 %, 0.27 %, and 0.66 %) are also significantly lower than those of Fe and Mo (14 % and 24 %). In addition to the record-breaking reduction in the titanium dissolution rate, W doping also substantially enhances the saturated adsorption capacity of lithium to 48 mg g⁻¹ (at 30 °C), 1.37 times that of the undoped LTO (35 mg g⁻¹), demonstrating great potential for lithium recovery.