A novel Co-doped H2TiO3 spinning composite for efficient lithium recovery from alkaline lithium precipitation mother liquor

Abstract

The efficient recovery of lithium from the alkaline mother liquor with high Na/Li ratios after Li2CO3 precipitation by adsorption has received extensive attention. However, synthesizing composite adsorbents with excellent adsorption capacity and rate still faces huge challenges. In this work, we synthesized a novel Co-doped Li2TiO3 lithium ion sieve (LTO-1/32Co) using the calcination method. After converting to Co-doped H2TiO3 (HTO-1/32Co) by pickling, the adsorption capacity of the material was 1.4 times higher than that of conventional H2TiO3. To realize the industrial application of the powdered HTO-1/32Co, it was coated with polysulfone (PSF) by the wet spinning method. The saturated adsorption capacity of the material could reach 60.79 mg·g−1, which was at the forefront of reported composite adsorbents. When the adsorbent was applied for lithium recovery from lithium precipitation mother liquor, the adsorption capacity could reach 40.12 mg·g−1, and the equilibrium time was only 50 min. The elution rate of Li+ could be maintained at 90.56 % with the dissolution loss of Ti no more than 0.43 % after six cycles. The developed fibrous composite adsorbent exhibits excellent adsorption/desorption performance and cyclic stability, making it a competitive candidate for efficient lithium recovery from lithium precipitation mother liquor and other lithium-rich alkaline brine resources.