The solubility of cefquinome sulfate in pure and mixed solvents

Solid-liquid equilibrium data of cefquinome sulfate is important to develop industrial crystallization processes for cefquinome sulfate. The solubilities of cefquinome sulfate in five pure solvents （methanol, ethanol, ethylene glycol, acetic acid and water） from 277.15 to 305.15 K and in a binary acetone-water solvent from 278.15 to 293.15 K were measured at atmospheric pressure. The pure-solvent solubility data was correlated to the modified Apelblat and Van＇t Hoff equations whereas the mixed-solvent system data was correlated to the modified Apelblat, Van＇t Hoff, CNIBS/R-K and Jouy- ban-Acree models. It was found that the solubilities of cefquinome sulfate in all tested solvents decreased with the increasing of temperature. In addition, the thermodynamic properties of the dissolution processes, including standard Gibbs free energy, enthalpy and entropy changes, were calculated using the Van＇t Hoff equation. It was found that the dissolution of cefquinome sulfate is exothermic.