Solubility Determination and Thermodynamic Analysis of Clioquinol in Ten Pure Solvents and Three Binary Solvents at 273.15 to 318.15 K

The solubility of clioquinol in ten different pure solvents─specifically methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, acetonitrile, ethyl acetate, toluene, and acetone─as well as in three binary mixtures containing methanol combined with acetone, ethyl acetate, or toluene was determined using the static equilibrium method combined with HPLC. The temperature range under ambient pressure was from 273.15 to 318.15 K. Data revealed that clioquinol demonstrated maximum solubility in toluene and minimum in methanol as the temperature rose. In binary solvent systems, clioquinol solubility increased with the molar ratio of the more effective solvent. The solubility figures obtained from pure solvents were correlated using the Modified Apelblat model, the λh model, and the CNIBS/R-K model, while the Jouyban–Acree model and the SUN model were applied for the binary solvent mixtures. Thermodynamic model accuracy was verified through relative average deviation (RAD) and root-mean-square deviation (RMSD) calculations of the fitting outcomes. Finally, the KAT-LSER model was utilized to examine how solvent characteristics impact pure solvent solubility.