Optimization of Ion Migration During Lithium‐Ion Recovery Through Electrodialysis by Numerical Simulations

ABSTRACT Electrodialysis plays an important role in lithium extraction from brine. A two‐dimensional mathematical model for steady electrolyte transport during electrodialysis desalination is constructed in this study to uncover the mechanism of lithium‐ion transfer and forecast the behavior of electrodialysis. The effects of ionic charge number, ion diffusion coefficient, applied voltage, and channel flow rate on mass transfer are examined by analyzing the distributions of the lithium‐ion concentration, electric potential, and flux in an electrodialysis device. Results demonstrate that an increase in the ionic charge number resulted in an increase in both the electromigration flux and the total flux. Ionic charge is the primary factor influencing ion flux. The larger the diffusion coefficient, the greater the total transfer flux and electromigration flux of Li + . High applied voltages and channel flow rates are beneficial for increasing the overall Li + transfer flux. Furthermore, model validity is confirmed by comparing simulation results with experimental electrodialysis data. This study aims to develop a complete model for lithium recovery through electrodialysis by rationalizing and integrating previously neglected assumptions. It elucidates the sensitivity of the electrodialysis process to various parameters and provides guidelines for optimizing design, material selection, and operating conditions. Furthermore, the model can be employed to narrow the parameter range for experimental investigations of selectivity, thereby offering theoretical guidance and data references to facilitate the process optimization of electrodialysis‐based lithium‐ion recovery.