Li_(1.6)Mn_(1.6)O_4/PVDF多孔膜的制备及提锂性能

Preparation of Li_(1.6)Mn_(1.6)O_4/PVDF membrane and its lithium uptaking

自制锂离子筛前驱体Li1.6Mn1.6O4,并将Li1.6Mn1.6O4粒子与高分子树脂PVDF杂化制膜,研究了膜经稀盐酸抽锂后对锂的吸附性能以及多次吸附与脱附性能等。结果表明,膜M-10-55[Li]采用0.5 mol·L-1 HCl溶液抽锂约2 h锂的脱出基本达到平衡,Li+的洗脱率在95%左右,锰的溶损率为3.5%左右。抽锂后得M-10-55[H]对富锂溶液中锂的吸附约12 h达平衡,对锂的吸附容量较高为41 mg·g-1,在第5次吸附时对锂的提取量为35 mg·g-1左右。相比于Na+、K+、Mg2+、Ca2+,该膜对Li+表现出较好的选择性,对于从海水、盐湖卤水等液态锂资源中提取锂有很大的开发潜力。

Spinel-type manganese oxide Li1.6Mn1.6O4 was prepared. It was mixed with poly（vinylidene fluoride） （PVDF） and flat membrane was obtained for recovering lithium from lithium-containing waters by a solvent exchange method. After the membrane was treated with an HCI solution it can uptake lithium. A series of experiments for examining its adsorption and reuse were carried out. Results showed that when membrane M-10-55[Li] was treated with 0.5 mol · L-1 HC1 solution for 2 h, the lithium extraction reached equilibrium and about 95% lithium was extracted, and the rate of manganese dissolution was about 3.5%. The membrane M-10-55[H] obtained showed good performance in adsorption capacity to Li＋ （about 41 mg · g^-1）, and when used for the fifth time it still had an adsorption capacity of 35 mg · g^-1. The membrane can selectively adsorb Li＋ better compared with Na＋, K＋, Mg2＋ and Ca2＋. It is potential to be used in enrichment and recovery of lithium from seawater and other liquid lithium sources.