Solubility of Dimethyl 2,2′-Azobis(2-methylpropionate) in 15 Pure Solvents and in a Methanol plus Water Binary Solvent System

The solubility of dimethyl 2,2'-azobis(2-methylpropionate) (AIBME) was determined in 15 pure solvents, including cyclohexane, dichloromethane, diethyl ether, acetone, tetrahydrofuran, ethyl acetate, tetrachloromethane, acetonitrile, methylbenzene, methanol, ethanol, n-propyl alcohol, isopropanol, n-butyl alcohol, and iso-butyl alcohol, and in a binary solvent system (methanol + water at the temperature range from 253.15 to 293.15 K at atmospheric pressure. Between 278.15 and 293.15 K, the solubility of AIBME is more sensitive to temperature in alcohol solvents than in other solvents. However, the solubility of AIBME in nonalcoholic solvents decreased more rapidly than in alcohol solvents below 278.15 K. The AIBME solubility in the binary solvent system (methanol + water is positive to temperature and the initial mole fraction of methanol. The measured solubility data of AIBME in pure solvents were correlated by the modified Apelblat equation, the lambda h equation, the nonrandom two-liquid (NRTL) model, and the Wilson model. The measured solubility data of AIBME in binary solvent systems were correlated by the modified Apelblat equation, the nonrandom two-liquid (NRTL) model, and the Wilson model. Among the four models, the NRTL model is the best model to fit the solubility of AIBME, especially in alcohol solvents. In addition, the mixing properties of AIBME in 15 pure solvents, including standard mixing Gibbs energy, mixing enthalpy, and mixing entropy, were calculated and discussed. The results provide useful information for practical optimization of AIBME crystallization processes.