Solubility Measurement and Correlation of Ceftiofur Sodium Trihydrate in Four Binary Solvent Mixtures

The solubility of ceftiofur sodium trihydrate (CST) in binary solvent mixtures of water + acetonitrile, water + ethanol, water + n-propanol, and water + iso-propanol at temperatures from 273.15 to 313.15 K (P = 0.1 MPa) was measured by a laser dynamic method. The experimental results show that the solubility is positively correlated with temperature. In the four binary solvent systems, the solubility value of CST initially increases first and then decreases with increasing organic solvent composition. The maximum solubility values occur in the molar content of organic solvent of about 0.5 for water + acetonitrile, 0.5 for water + ethanol, 0.4 for water + n-propanol, and 0.4 for water + iso-propanol. The accuracy of experimental results was examined by the Apelblat model, the Van’t-JA model, and the Apel-JA model, and the Apelblat model shows the best fitting performance.