Solubility Behavior and Data Modeling of l‑Proline in Different Neat and Binary Solvent Systems

The mole fraction solubility data of l-proline in five monosolvents (water, methanol, ethanol, acetone, and acetonitrile) and four binary solvent systems (methanol + acetone, ethanol + acetone, methanol + acetonitrile, and ethanol + acetonitrile) were experimentally measured by gravimetric method at temperatures ranging from 283.15 to 323.15 K. The results showed that l-proline solubility and experimental temperature were positively correlated when the solvent composition was constant. On the basis of the solubility scatter diagrams and our investigation of solvent properties, the solubility behavior of l-proline in the pure and binary solvent systems was influenced by a combination of many factors. The solubility data were correlated by the modified Apelblat model, CNIBS/R-K model, and Apelblat-Jouyban-Acree model. The fitting results were generally acceptable.