Determination and correlation of solubility and solution thermodynamics of valnemulin hydrogen tartrate in different pure solvents

The solubility of valnemulin hydrogen tartrate in five pure solvents was determined in temperature range of 278.15 K to 333.15 K by using a static analytical method. Five thermodynamic models were used to correlate the experimental solubility data. The correlated results were analyzed and compared with experimental results. It was found that the correlated results were in good agreement with the experimental results. By using the Van’t Hoff equation, the dissolution enthalpy and entropy of valnemulin hydrogen tartrate in different solvents were calculated. The mixing thermodynamic properties of valnemulin hydrogen tartrate, including the mixing Gibbs energy, the mixing enthalpy and entropy, as well as the infinite-dilution activity coefficient and the excess enthalpy, were determined by using the Wilson model and the experimental solubility data.