Recently, the rapid development of new energy industry has promoted a sharp increase in the demand for lithium (Li). The adsorption method has notably contributed to the recovery of lithium. However, the poor adsorption capacity and selectivity as well as the complicated preparation process of current adsorbents hinder the development of lithium adsorption. Herein, we adopted a simple and green low-temperature phase separation method to fabricate a chitosan (CS) nanofiber membrane. The specific surface area of the prepared membrane is as high as 111.55 m² g⁻¹. Meanwhile, for the sake of high selectivity for Li⁺, we chose 2-(Hydroxymethyl)-12-crown 4-Ether (2H12C4) with a unique cavity structure to graft onto the surface of CS to prepare crown ether (CE) modified chitosan nanofiber membranes (CS-CE). The results show that CS-CE achieved the maximum adsorption capacity of 297 mg g⁻¹ from a high-concentration Li⁺ solution with 1000 mg L⁻¹ at pH 7.0. In a mixed solution coexisting with other interfering metal ions, CS-CE still exhibited a strong affinity for Li⁺. In addition, after 5 cycle experiments, the maximum adsorption capacity of CS-CE for Li⁺ decreased by only 8.8%, which proves the excellent reusability of CS-CE. Overall results suggested that CS-CE can be a promising candidate for the recovery of Li⁺.

近来，新能源产业的快速发展促进了锂（Li）需求的急剧增加。吸附法对锂的回收有显着贡献。然而，不良的吸附容量和选择性以及当前吸附剂的复杂制备过程阻碍了锂吸附的发展。本文中，我们采用一种简单而绿色的低温相分离方法来制备壳聚糖（CS）纳米纤维膜。制备的膜的比表面积高达111.55m ² g ^-1。同时，由于对Li ⁺的高选择性，我们选择具有独特腔结构的2-（羟甲基）-12冠4醚（2H12C4）接枝到CS表面，以制备冠醚（CE）改性的壳聚糖纳米纤维膜（CS-CE）。结果表明，CS-CE在pH 7.0下从1000 mg L ^-1的高浓度Li ⁺溶液中获得的最大吸附容量为297 mg g ^-1。在与其他干扰金属离子共存的混合溶液中，CS-CE仍显示出对Li ⁺的强亲和力。另外，经过5次循环实验，CS-CE对Li ⁺的最大吸附量仅降低了8.8％，证明了CS-CE具有极好的可重复使用性。总体结果表明，CS-CE有望成为恢复锂的有前途的候选者⁺。