Solubility of maleic anhydride in methanol + (acetone, ethyl acetate) from 278.15 to 323.15 K

The solubilities of maleic anhydride in methanol + (acetone, ethyl acetate) mixed solvents were measured within the temperature range of 278.15-323.15 K at atmospheric pressure by the gravimetric method. The solubility of maleic anhydride in those mixed solvents increased with increasing temperature, but the rate of solubility is different. In addition, the solubility of maleic anhydride also increased with the increasing mass fraction of methanol. The experimental data were well-correlated with the modified Apelblat equation, the λh equation and the van't Hoff equation. Moreover, the calculated solubilities shown good agreement with the experimental results. It was found that the modified Apelblat equation could obtain the better correlation results than the other two models. The thermodynamic properties of the solution process, including the enthalpy, and entropy were calculated by the van't Hoff analysis and they were positive. What's more, the experimental data and model parameters would be useful for optimizing the process of purification of maleic anhydride in industry.