Advanced Lithium Extraction Membranes Derived from Tagged-Modification of Polyamide Networks |
| |
Authors: | Huawen Peng Xufei Liu Yafei Su Jiapeng Li Prof Qiang Zhao |
| |
Institution: | Key Laboratory of Material Chemistry for Energy Conversion and Storage, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, 430074 Wuhan, P.?R. China |
| |
Abstract: | Efficient Mg2+/Li+ separation is crucial to combating the lithium shortage worldwide, yet current nanofiltration membranes suffer from low efficacy and/or poor scalability, because desirable properties of membranes are entangled and there is a trade-off. This work reports a “tagged-modification” approach to tackle the challenge. A mixture of 3-bromo-trimethylpropan-1-aminium bromide (E1) and 3-aminopropyltrimethylazanium (E2) was designed to modify polyethylenimine – trimesoyl chloride (PEI-TMC) membranes. E1 and E2 reacted with the PEI and TMC, respectively, and thus, the membrane properties (hydrophilicity, pore sizes, charge) were untangled and intensified simultaneously. The permeance (34.3 L m?2 h?1 bar?1) and Mg2+/Li+ selectivity (23.2) of the modified membranes are about 4 times and 2 times higher than the pristine membrane, and they remain stable in a 30-days test. The permeance is the highest among all analogous nanofiltration membranes. The tagged-modification method enables the preparation of large-area membranes and modules that produce high-purity lithium carbonate (Li2CO3) from simulated brine. |
| |
Keywords: | Anti Trade-Off Interfacial Polymerization Lithium Extraction Nanofiltration Tagged-Modification |
|
|