Lithium (Li) batteries play an important role in powering the modern world. The demand of Li continuously grows as technologies advance and new applications emerge. It is critical to establish a U.S. domestic lithium supply chain. While Li can be produced via traditional chemical separation technologies, it has been reported that direct lithium extraction using membrane technologies is more economically viable and environmentally friendly. The primary challenge lies in low selectivity of Li+ over other competing ionic species such as sodium (Na+) and potassium (K+) due to similar size and charge. Crown ethers are promising for selective lithium separation as they can form complexes with Li+ through an ion-dipole interaction, and electrodialysis using crown ether-based polymer membranes enables a continuous extraction and transport of Li+ from source brines to product water with high efficiency.
In this talk, we will present design and synthesis of crown ether-based molecules for Li separation membrane development, which is guided by atomic-scale computational models. The crown ether-based polymer and membrane fabrications will also be presented.