Abstract: The present application discloses a lithium extraction method for an alkaline solution, in which a lithium adsorption material is used in an alkaline environment. Lithium ions in the alkaline solution are adsorbed, the lithium adsorption material is replaced with an alkaline high-lithium low-impurity solution, and then an acid solution is used for desorption, so that a high-lithium salt solution having higher lithium content can be obtained. Lithium concentration can reach 5 g/L or more, and the high-lithium salt solution can enter a bipolar membrane system for electrolysis, thereby preparing an alkaline high-lithium low-impurity solution and an acid solution for replacement and desorption of the lithium adsorption material. In the method provided by the present application, lithium in an alkaline solution is adsorbed by resin, and the lithium is preliminarily separated from sodium and potassium.

Abstract: A method for lithium adsorption in a carbonate- and/or sulfate-containing solution, comprising using an aluminum-based lithium adsorbent for adsorption of lithium ions in the carbonate- and/or sulfate-containing solution, after the adsorption is saturated, using a weakly acidic high-concentration salt solution to transform the adsorbent, desorbing the transformed adsorbent by means of a low-concentration salt solution or water, and entering the next cycle for operation.