Advanced Lithium Extraction Membranes Derived from Tagged-modification of Polyamide Networks

Angew Chem Int Ed Engl. 2023 Oct 5:e202312795. doi: 10.1002/anie.202312795. Online ahead of print.ABSTRACTEfficient 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 trade-off. This work reported a "tagged-modification" chemistry to tackle the challenge. A mixture of 3-bromo-trimethylpropan-1-aminium bromide (E1) and 3-aminopropyl-trimethylazanium (E2) was designed to modify polyethylenimine - trimesoyl chloride (PEI-TMC) membranes. E1 and E2 reacted with the PEI and TMC, respectively, and thus, membrane properties (hydrophilicity, pore sizes, charge) were untangled and intensified simultaneously. Permeance (34.3 L m-2 h-1 bar-1) and Mg2+/Li+ selectivity (23.2) of modified membranes are ~4 times and ~2 times higher than the pristine membrane, and 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.PMID:37796136 | DOI:10.1002/anie.202312795
Source: Angewandte Chemie - Category: Chemistry Authors: Source Type: research