Solubility and thermodynamic analysis of 1,6-Hexanediol in (methanol + dimethyl adipate) and (n-butanol + dimethyl adipate) binary solvents from 283.15 K to 303.15 K

The solubility of 1,6-Hexanediol in (methanol + dimethyl adipate (DMA)), (n-butanol + DMA) binary solvents was measured by the dynamic method under 0.1 MPa. The studies were carried out at different mass fractions of methanol or n-butanol from 283.15 K to 303.15 K. The solubility of 1,6-Hexanediol in binary solvents increases with increasing temperature and mass fraction of methanol or n-butanol. In a fixed temperature and fixed mass fraction of methanol or n-butanol, the solubility of 1,6-Hexanediol in (methanol + DMA) is greater than in (n-butanol + DMA). In addition, the experimental solubility data were correlated by Jouyban-Acree model, Van't Hoff-Jouyban-Acree model, modified Apelblat-Jouyban-Acree model and Sun model, in which the Sun model shows the best agreement with the experimental solubility data. The maximum of relative average deviation (RAD) and the root-mean-square deviation (RMSD) between the experimental and calculated solubility were 5.85 × 10− 2 and 3.80 × 10− 2, respectively. Additionally, the thermodynamic properties (including enthalpy, Gibbs energy and entropy) were also obtained, and the results show that the dissolution of 1,6-Hexanediol in the two binary solvents is an endothermic process.