【摘要】 锂离子吸附剂/聚合物复合纳米纤维膜是近年来盐湖卤水提锂领域的新兴材料，具有绿色环保、可重复利用等优势，未来有望成为该领域的最佳选择。本研究将钛基锂离子吸附剂(LTO)、铝基锂离子吸附剂(LDH)分别与聚偏氟乙烯(PVDF)、聚乳酸(PLA)和聚氯乙烯(PVC)3种聚合物单独混合，采用静电纺丝技术制备了不同种类的LTO/聚合物、LDH/聚合物复合纳米纤维膜；利用0.2 mol/L HCl对LTO/聚合物复合纳米纤维膜酸洗脱锂，得到具有锂离子吸附位点的钛基锂离子吸附剂(HTO)/聚合物纳米纤维膜。实验探究了聚合物种类、混合溶液浓度、锂离子吸附剂占比及锂离子吸附剂类型对所得复合纤维膜结构与吸附性能的影响。结果表明，3种聚合物中，PVDF更适合与锂离子吸附剂混合进行静电纺丝，所得复合纤维膜中纤维直径均匀，且纤维对吸附剂的包覆效果较好；当电纺溶液中PVDF的质量分数为18%,HTO与PVDF质量比为70%时，制备的HTO/PVDF复合纳米纤维膜中纤维直径均一且纤维对吸附剂的包覆效果好。2种吸附剂/PVDF复合膜均具有优异的锂离子吸附效果，其中70%HTO/18%PVDF复合纤维膜的锂离子吸附容量为55.84 mg/g, 70%LDH/18%PVDF复合纳米纤维膜的锂离子吸附容量达到99.81 mg/g。更多还原

【Abstract】 Lithium-ion adsorbent/polymer composite nanofiber membranes are emerging materials in the field of lithium extraction from salt lake brine, with advantages such as being environmentally friendly and reusable, and are expected to become the preferred choice in this field in the future. In this study, titanium-based lithium-ion adsorbent(LTO) and aluminum-based lithium-ion adsorbent(LDH) were separately mixed with three polymers: polyvinylidene fluoride(PVDF), polylactic acid(PLA), and polyvinyl chloride(PVC), and different types of LTO/polymer and LDH/polymer composite nanofiber membranes were prepared using electrospinning technology. The LTO/polymer composite nanofiber membranes were acid-leached with 0.2 mol/L HCl to remove lithium, obtaining titanium-based lithium-ion adsorbent(HTO)/polymer nanofiber membranes with lithium-ion adsorption sites. The effects of polymer type, mixed solution concentration, adsorbent ratio, and adsorbent type on the structure and adsorption performance of the resulting composite fiber membranes were investigated. Results indicated that among the three polymers, PVDF was more suitable for mixing with lithium-ion adsorbents for electrospinning, producing composite fiber membranes with uniform fiber diameter and good adsorbent encapsulation. When the mass fraction of PVDF in the electrospinning solution was 18% and the HTO/PVDF mass ratio was 70%, the resulting HTO/PVDF composite nanofiber membrane exhibited uniform fiber diameter and effective encapsulation of the adsorbent. Both adsorbent/PVDF composite membranes demonstrated excellent lithium-ion adsorption, with the 70%HTO/18%PVDF composite fiber membrane achieving an adsorption capacity of 55.84 mg/g and the 70%LDH/18%PVDF composite nanofiber membrane achieving 99.81 mg/g.更多还原