Solubility Measurement, Data Correlation, and Solvent Effects of 1-Adamantanecarboxylic Acid in 9 Pure Solvents and Ethanol + Ethyl Acetate Binary Solvent Mixtures from 293.15 to 333.15 K

The solubility of 1-adamantanecarboxylic acid (1-ACA) was experimentally determined in 9 pure solvents and ethanol + ethyl acetate binary mixtures over the temperature range of 293.15–333.15 K using the gravimetric method. The solubility of 1-ACA increased with increasing temperature in all investigated solvents, and the solvent dissolving capability generally followed the order of alcohols > esters > acetonitrile. In ethanol + ethyl acetate mixtures, the solubility exhibited a maximum at an ethanol mass fraction of 0.40, indicating a significant cosolvent effect. The experimental solubility data were correlated using three semiempirical models and three activity coefficient models. The modified Apelblat model showed the best correlation performance, with average relative deviations of 1.1961% and 0.9131% for pure and mixed solvent systems, respectively. Dissolution in pure solvents was analyzed using the “like-dissolves-like” principle and Hansen solubility parameters. KAT-LSER analysis indicated that solvent cohesive energy and dispersion interactions were the dominant factors affecting 1-ACA solubility. The obtained solid–liquid equilibrium data provide valuable information for solvent selection and crystallization process optimization of 1-ACA.