Solid–liquid equilibria in the LiOH –ethanol–water system: Solubility measurements and thermodynamic modeling

The demand for LiOH is driven by the growth of the electric vehicle industry. Evaporative crystallization of LiOH·H 2 O is energy intensive, whereas ethanol‐based antisolvent crystallization has emerged as a more sustainable alternative. From a process design perspective, the crystallization yield depends on the ethanol dosage, and thermodynamic modeling of solid–liquid equilibria requires reliable equilibrium data for parameterization. However, existing LiOH solubility data in ethanol–water mixtures are limited to 298.15 K and low ethanol mass fractions (≤0.589). We addressed this gap by measuring LiOH solubilities in ethanol–water mixtures across the full range of ethanol mass fractions from 298.15 to 328.15 K and applying the Pitzer–Lorimer method for thermodynamic modeling. Solubilities at all solvent compositions were used for parameter fitting, resulting in a model with a mean relative deviation from the data of 2.19%. This work also provides a transferable workflow for future process optimization using other antisolvents in LiOH crystallization.