Solubility and dissolution thermodynamics of phthalic anhydride in organic solvents at 283–313 K

The solubility of phthalic anhydride was measured at 283–313 K under atmospheric pressure in ethyl acetate, n-propyl acetate, methyl acetate, acetone, 1,4-dioxane, n-hexane, n-butyl acetate, cyclohexane, and dichloromethane. The solubility of phthalic anhydride in all solvents increased with the increasing temperature. The Van’t Hoff equation, modified Apelblat equation, λh equation, and Wilson model were used to correlate the experimental solubility data. The standard dissolution enthalpy, the standard entropy, and the standard Gibbs energy were evaluated based on the Van’t Hoff analysis. The experimental data and model parameters would be useful for optimizing of the separation processes involving phthalic anhydride.