Development of multi-stage column for lithium recovery from an aqueous solution

Spinel lithium manganese oxides (LMOs) are the most effective lithium adsorbent for the recovery of lithium from an aqueous solution with high selectivity. Developing a systematic method to apply LMOs powder will have a profound impact on the effective and practical process of lithium recovery. We previously fabricated a reservoir system in which the LMO powder was packed in the inside of fabric membrane and then tested by dipping it in an aqueous solution. However, this method exhibited lower adsorption capacity compared with that of LMO powder by stirring in an aqueous solution. Here, we demonstrate a new method to selectively recover lithium from an aqueous solution through an integration of several columns filled with LMO powder. Briefly, our system comprises a series of columns equipped with fabric filters that accumulate LMO powder onto the fabric membrane in which the aqueous solution containing Li+ ion is introduced into the system by applying pressure. We report that the multi-stage column (MSC) uniformly packed with LMOs exhibited higher adsorption capacity (30.7 mg·g− 1) compared with that (12.3 mg·g− 1) of a reservoir system at a lithium concentration of 30 mg·L− 1. To confirm the feasibility of the multi-stage column (MSC), we also tested it to the recovery of lithium from Salt Lake, which was artificially manufactured.