In regards to the unique properties of lithium, lithium separation with high purity is crucial in various industries. Due to the close radii of alkali and alkaline earth metals, this is important to choose a technique with appropriate properties for ion separation in aqueous medium. Among the available methods for lithium enrichment, polymer inclusion membrane (PIM) system has features that meet the needs. In this study, a PIM containing green polyol as the base polymer, 12-Crown-4 (12C4) as the carrier and 1-butyl-3-methylimidazolium chloride (BMIMCl) ionic liquid was synthesized to separate lithium ion from an aqueous solution of Li⁺, Na⁺, K⁺, Ca^2+, and Mg²⁺. Also, the zeolitic imidazolate framework type ZIF-8 was employed in the membrane structure to improve Li⁺ enrichment process. Characterization techniques such as FTIR, AFM and SEM, verified that ZIF-8 was added to the PIM structure. The results showed that ZIF-8 nanoparticles increased the hydrophobicity and the roughness of PIM that resulted in more selectivity. In addition, this type of MOF has regular porosity that is a suitable pathway for ion transport across the membrane. This feature increases the ion flux of synthesized PIMs. In the optimum combination of membranes, lithium ion flux was 45.7 × 10⁻³ mmol⋅cm⁻²⋅h⁻¹ and 63 × 10⁻³ mmol⋅cm⁻²⋅h⁻¹ without ZIF-8 and with ZIF-8 nanoparticles, respectively. Also, polyvinylidene fluoride (PVDF), polyvinyl chloride (PVC), and cellulose acetate (CA) were employed as base polymer of PIM to evaluate the effect of polymer on the ion flux. The lithium flux of these polymers was 47.2 × 10⁻³ mmol⋅cm⁻²⋅h⁻¹, 44.3 × 10⁻³ mmol⋅cm⁻²⋅h⁻¹, and 24.98 × 10⁻³ mmol⋅cm⁻²⋅h⁻¹ that are respectively related to PVDF, PVC and CA base PIMs.

关于锂的独特性质，高纯度的锂分离在各个行业中至关重要。由于碱金属和碱土金属的半径很近，因此选择一种具有适当特性的水介质中离子分离技术非常重要。在可用的富集锂的方法中，聚合物包裹膜（PIM）系统具有满足需求的功能。在这项研究中，合成了一种PIM，包含绿色多元醇作为基础聚合物，12-Crown-4（12C4）作为载体和1-丁基-3-甲基咪唑鎓氯化物（BMIMCl）离子液体，以从水溶液中分离锂离子。 Li ⁺，Na ⁺，K ⁺，Ca ²⁺和Mg ²⁺。另外，在膜结构中采用ZIF-8型沸石咪唑酸盐骨架来改善Li ⁺富集过程。诸如FTIR，AFM和SEM的表征技术验证了ZIF-8已添加到PIM结构中。结果表明，ZIF-8纳米颗粒增加了PIM的疏水性和粗糙度，从而提高了选择性。另外，这种类型的MOF具有规则的孔隙率，这是离子跨膜传输的合适途径。此功能增加了合成PIM的离子通量。在膜的最佳组合中，锂离子通量为45.7×10 ^-3 mmol·cm ^-2· h ^-1和63×10 ^-3 mmol·cm ^-2· h ^-1不含ZIF-8和含ZIF-8纳米颗粒。此外，聚偏二氟乙烯（PVDF），聚氯乙烯（PVC）和醋酸纤维素（CA）被用作PIM的基础聚合物，以评估聚合物对离子通量的影响。这些聚合物的锂通量为47.2×10 ^-3 mmol⋅cm ^-2 ⋅h ^-1，44.3×10 ^-3 mmol⋅cm ^-2 ⋅h ^-1，和24.98×10 ^-3 mmol⋅cm ^-2 ⋅h ^-1，分别与PVDF，PVC和CA基本PIM相关。