Thermodynamic models for determination of the solubility of 4-(4-aminophenyl)-3-morpholinone in different pure solvents and (1,4-dioxane + ethyl acetate) binary mixtures with temperatures from (278.15 to 333.15) K

Highlights: • The solubility in pure solvents and in binary mixtures was investigated. • The modified Apelblat equation and other models were used for researching the solubility. • The Gibbs energy, enthalpy and entropy were calculated by the van't Hoff analysis. - Abstract: A gravimetric method was used to measure the solubility of the 4-(4-Aminophenyl)-3-morpholinone under atmospheric pressure in 1,4-dioxane, methanol, tetrahydrofuran, ethanol, ethyl acetate, n-propanol as well as in the (1,4-dioxane + ethyl acetate) binary mixtures from T = (278.15 to 333.15) K. The experiment results have proved that rising temperature leads to increased solubility of the 4-(4-aminophenyl)-3-morpholinone in all selected solvents. The (solid + liquid) equilibrium data in six pure solvents and binary mixtures were correlated with four equations, including the modified Apelblat equation, the Buchowski−Ksiazaczak λh equation, CNIBS/R–K equation and the Jouyban–Acree equation. During the research, the computational values were in good agreement with the experimental results according to the calculations based on all selected equations, and the modified Apelblat equation stood out to be the higher suitable with the higher accuracy. The thermodynamic properties of the solution process, including the Gibbs energy, enthalpy, and entropy were calculated by the van't Hoff analysis. All values of %ξ_H are ⩾60.35% indicated that in each studied solvent the dissolution process of 4-(4-aminophenyl)-3-morpholinone is endothermic.