A closed-loop process for selective lithium recovery from brines via electrochemical and precipitation

Abstract

With the growing demand for lithium from electric vehicles, efficient recovery of lithium from brines is attracting more attention. However, it is difficult to produce high purity lithium carbonate (Li2CO3) from brine in a rapid and energy-efficient manner. In this work, a closed-loop process was developed to recover lithium from brine and produce high-purity Li2CO3. The lithium in the brine was first selectively recovered by Electrochemical Deintercalation/Intercalation system (EDIs), and then a high concentration of lithium solution was obtained by precipitation, which replaced the traditional time-consuming evaporation process. The lithium yield of each step was above 87%, and the purity of Li2CO3 reached the battery-grade standard after three times washing. In addition, the Fe3+ and PO43- used in the process can be reused, and basically no waste residue was generated. This research has potential applications in the rapid concentration of low Li+ concentration solution obtained from brine and the preparation of high purity Li2CO3.