Li+ enrichment behavior in a sodium sulfate and low carbonate salt lake brine

Abstract

The Laguo salt lake has both carbonate- and sodium-sulfate-type characteristics, and is famous for its resources, such as Li, B, K, Rb and Cs. Accordingly, it may be a potential source of lithium. The concentration of SO42− is known to influence the evaporation process of brine enriched in lithium. Isothermal evaporation experiments show that Li+ precipitates as Li2SO4·H2O, which is very unfavorable for lithium enrichment processes. Therefore, a series of temperature-variation experiments were conducted to effectively control the concentration of SO42− in the brine. The SO42− content was reduced by lowering the brine temperature, and thus the desulfurization target was achieved, and the precipitation of lithium was controlled. At the same time, the Mg/Li, which is known to affect Li extraction, was reduced. From the temperature-variation experiments, we successfully obtained a high-lithium brine can be obtained. Our results should provide a theoretical basis for the enrichment of lithium and the efficient utilization of resources in a composite salt lake brine.