Solubility Measurement and Thermodynamic Modeling for o-Toluenesulfonamide in 16 Solvents from T = 273.15 to 323.85 K

The solid–liquid equilibrium data of o-toluenesulfonamide in 16 pure organic solvents, including methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, n-pentanol, isopentanol, acetone, ethyl acetate, acetonitrile, cyclohexanone, cyclopentanone, methyl acetate, ethyl formate, and dichloromethane, were measured by a static gravimetric method with the temperature ranging from 273.15 to 323.85 K under atmospheric pressure. The results showed that the solubility of o-toluenesulfonamide increased with the increasing temperature in all the solvents studied. The experimental solubility data were correlated by the modified Apelblat equation, λh equation, nonrandom two-liquid (NRTL) equation, and Wilson equation. All the models could be well employed, and the NRTL model gave the best fitting results.