Investigating the impact of temperature and concentration on membrane-assisted crystallization of lithium fluoride solution

Lithium fluoride (LiF) is a versatile compound widely used in optics, ceramics, nuclear technology, and lithium-ion batteries due to its excellent electrochemical stability and ionic conductivity. In batteries, LiF forms stable solid electrolyte interphases (SEI), improving performance, efficiency, and longevity. However, the extensive use of batteries raises sustainability concerns due to waste and pollution, driving attention to recycling as a solution for environmental and economic challenges (Ramirez et al., 2024; Battaglia et al., 2022). Recovering critical metals like lithium and cobalt has become essential, with reactive crystallization techniques emerging as key solutions. Membrane-assisted crystallization (MAC) has shown great promise in lithium recovery, utilizing hydrophobic membranes like polypropylene (PP) to selectively transport water vapor while retaining lithium salts, enabling controlled supersaturation and crystallization. This process enhances recovery efficiency and aligns with circular economy principles (Alessandro et al., 2024). Our study uses molecular dynamics (MD) simulations to explore LiF crystallization behavior in MAC systems (Prenesti et al., 2025). Simulations conducted with GROMACS 5.1.4 (Abraham et al., 2015) and VMD 1.9.3 (Humphrey et al., 1996) modeled water using the SPC/E model and ions with the OPLS force field. Systems at varying concentrations were equilibrated under NPT ensembles, followed by 300 ns production runs at different temperatures and 1 atm. Results highlight how hydrophobic membranes influence nucleation and crystal growth under different supersaturation conditions, demonstrating their role in stabilizing nuclei and shaping crystal morphology. These insights pave the way for efficient and sustainable lithium recovery technologies.