Systems and methods for electrochemical extraction of a target ion

A system for electrochemical extraction of a target ion, the system comprising:

• at least one set of alternating sorbent chambers and eluate chambers defined by a plurality of alternating ion exchange membranes, the plurality of alternating ion exchange membranes being:
• at least one set of alternating anion exchange membranes and cation exchange membranes, or at least one set of alternating bipolar membranes and cation exchange membranes;
• wherein each of the ion exchange membranes forms a boundary between the alternating sorbent chambers and eluate chambers;
• wherein each of the ion exchange membranes are in electrochemical and liquid communication with a neighboring pair of sorbent chambers and eluate chambers;
• wherein each of the sorbent chambers further contains a target ion-selective sorbent;
• a pair of terminal electrodes;
• and
• a power source;
• wherein the pair of terminal electrodes and the power source are configured to apply an electrical field across the alternating sorbent chambers and eluate chambers when a closed circuit is formed between the pair of terminal electrodes and power source;
• wherein, during operation, the system is configured to sequentially operate an adsorption stage and a desorption stage;
• wherein, during the adsorption stage:
• the pair of terminal electrodes are not connected to the power source, such that no electrical field is applied across the alternating sorbent chambers and eluate chambers,
• each sorbent chamber is configured to receive a feed solution comprising the target ion, thereby contacting the target ion-selective sorbent with the feed solution, such that the target ion-selective sorbent selectively adsorbs the target ion from the feed solution;
• subsequently, during the desorption stage:
• each sorbent chamber is configured to receive a diluate solution;
• each eluate chamber is configured to receive a receiving solution;
• wherein the diluate solution and receiving solution each have an initially low concentration of the target ion;
• a closed circuit is formed between the pair of terminal electrodes and the power source, such that the pair of terminal electrodes and the power source are configured to apply an electrical field across the alternating sorbent chambers and eluate chambers;
• such that the target ion adsorbed by the target ion-selective sorbent elutes from the target ion-selective sorbent to the receiving solution, thereby forming a target ion recovery solution.