Developing effective technologies for the extraction of lithium from seawater and salt-lake brines is paramount for sustainable lithium reuse in battery industries. Conventional adsorption technology for extracting lithium from brines has been limited due to the low adsorption rate and dissolution of adsorbents. Here, we report a novel flow-type electrochemical lithium recovery system based on mesoporous λ-MnO₂/LiMn₂O₄ modified three-dimensional flow-through graphite felt electrodes. The mesoporous LiMn₂O₄ has a specific surface area of 183 m²/g, which provides a large solid-liquid interface for Li⁺ intercalation and deintercalation of LiMn₂O₄ phases. The three-dimensional graphite felt conductor could support abundant electroactive LiMn₂O₄ adsorbents and enhance the important diffusion and migration effects. In operation, a constant potential was applied on the cells to absorb Li⁺ by mesoporous λ-MnO₂ from brine and desorb Li⁺ from mesoporous LiMn₂O₄ into recovery solution simultaneously. This system is successful to extract lithium of 75 mg/h per gram LiMn₂O₄, with a Li/Mg separation coefficient of 46 and energy consumption of 23.4 Wh/mol. This study highlights the remarkably electrochemical activity, quick mass-transfer kinetics, and excellent stability of the mesoporous LiMn₂O₄@GF electrode, and provides an energy-efficient method for the recovery of Li⁺ from brines with high Mg²⁺/Li⁺ ratios.

开发用于从海水和盐湖盐水中提取锂的有效技术对于电池行业中可持续的锂再利用至关重要。由于低的吸附速率和吸附剂的溶解，限制了从盐水中提取锂的常规吸附技术。这里，我们报告基于中孔λ-MnO的一种新的流式电化学锂回收系统₂ /的LiMn ₂ ö ₄改性三维流通石墨毡电极。介孔LiMn ₂ O ₄的比表面积为183 m ² / g，为Li ⁺嵌入和脱嵌LiMn ₂提供了较大的固液界面O ₄相。三维石墨毡导体可以负载大量的电活性LiMn ₂ O ₄吸附剂，并增强重要的扩散和迁移效果。在操作中，一个恒定的电位被施加在细胞吸收锂⁺由介孔λ-MnO的₂从盐水和解吸锂⁺从孔的LiMn ₂ ö ₄进入恢复溶液同时进行。该系统成功提取了每克LiMn ₂ O ₄ 75 mg / h的锂，Li / Mg分离系数为46，能耗为23.4 Wh / mol。这项研究突出了介孔LiMn ₂ O ₄ @GF电极的显着电化学活性，快速的传质动力学和出色的稳定性，并提供了一种从高Mg ²⁺ / Li盐水中回收Li ⁺的节能方法。⁺比率。