The effect of solvents on solid-liquid phase equilibrium of Dimethyl sulfone

Abstract The structure and properties of Dimethyl sulfone (DMSO2) were investigated in both solid state and solution phase. In particular, the effect of four categories of solvent properties including hydrogen bonding donor and acceptor propensity, solvent polarity and cohesive energy density on solid-liquid phase equilibrium of DMSO2 were examined in detail. The intermolecular interactions derived from Hirshfeld surface analysis demonstrate that the C H⋯O interactions are dominant in crystal packing of DMSO2. The equilibrium solubility of DMSO2 was then determined in twelve monosolvents including water, straight and branch chain lower alcohols, and esters using gravimetrical method in the temperature ranging from 283.15 to 323.15 K. As expected, the solubility data is positively correlated with temperature, and DMSO2 bears the highest solubility in methyl acetate among all studied solvents. Further, it was found that the solubility of DMSO2 shows good correlation with cohesive energy density or the polarity of solvents except for the two lower alcohols of branch chain. The latter is likely due to other factors of solvent molecule involved such as steric hindrance, shape and size. Finally, the experimental data were well fitted by four thermodynamic models, and the modified Apelblat equation achieves the best fitting performance.