Determination and correlation of solubility and thermodynamic properties of l-methionine in binary solvents of water + (methanol, ethanol, acetone)

• The solubility data of l-methionine in three different binary mixed solvents were experimentally determined.
• The experimental solubility data of l-methionine were correlated by three models.
• Almost all studied solutions show good agreement with the “like dissolves like” empirical rule.
• Thermodynamic properties of l-methionine dissolution process were calculated and studied.

The solubility of l-methionine in three different binary mixed solvents of water + (methanol, ethanol, acetone) were experimentally measured by gravimetric method from T = (283.15 to 313.15) K (P = 0.1 MPa). The experimental data indicate that the solubility of l-methionine in the binary mixed solvents increases with the increasing temperature and decreases with the rise of molar concentration of organic solvents. The modified Apelblat model, the λh model and the CNIBS/R–K model were used to correlate the experimental data, and all of the models provided good fitting to the data. Furthermore, the mixing thermodynamic properties of l-methionine in different binary solvent mixtures were also calculated and discussed. The results indicate that the mixing process of l-methionine in the investigated solvents is endothermic and spontaneous. The experimental solubility and correlation equations can be used as essential data and simulation models in the purification and separation of l-methionine.