Innovative lithium recovery technique from seawater by using world-first dialysis with a lithium ionic superconductor

Hoshino, Tsuyoshi

Lithium (Li) procurement is becoming a matter of importance worldwide. Herein, I propose a method for recovering Li from seawater by using world-first dialysis, wherein Li only permeates from the negative electrode side to the positive electrode side through a Li ionic superconductor functioning as a Li separation membrane (LISM). Measurements of the Li ion concentration at the positive electrode side as a function of dialysis duration showed that the Li concentration increased to approximately 7% after 72 h with no applied electric voltage. Moreover, other ions in the seawater did not permeate the LISM. With both ends of the LISM bound with a negative and positive electrode, hydrated Li ion was transformed to Li ion only because Li ion can permeate through the LISM. This new recovery method shows good energy efficiency and is easily scalable and is thus suitable for the industrialized mass production of Li in South American countries, which have briny water containing Li.