Facile synthesis of degradable CA/CS imprinted membrane by hydrolysis polymerization for effective separation and recovery of Li⁺

Lithium resources are attractive for different applications because of their specific properties. Therefore, it is more significant to find a cost-effective and environment-friendly method to selective adsorption and recovery of Li⁺. In this work, a renewable and easy degradable CA/CS hybrid membrane was modified with polydopamine as adhesion layer to anchored TiO₂. The simple imprinting process could be realized by hydrolysis polymerization. The adsorption process followed Langmuir isotherm model and pseudo-second-order kinetic equation were researched in detail. The results displayed the maximum adsorption capacity is 20.08 mg g⁻¹ for Li⁺. The selectivity factors of Li⁺ to Na⁺, K⁺, Mg²⁺ and Ca²⁺ are 1.78, 2.43, 2.60 and 3.61, respectively, which mainly attributed to imprinting effect. The LIICMs also exhibited the superior reusability and durability. Thus, the LIICMs provide a powerful tool for selective separation and recovery of Li⁺ from mixed solutions.