Experimental measurement and thermodynamic models for solid–liquid equilibrium of hyodeoxycholic acid in different organic solvents

Data on corresponding solid–liquid equilibrium of hyodeoxycholic acid (HDCA) in different solvents is essential for a preliminary study of industrial applications. In this paper, the solid–liquid equilibrium of HDCA in methanol, ethanol, isopropyl alcohol, butan-1-ol, ethyl acetate , acetone, acetonitrile , and acetic acid was explored at temperatures ranging from 278.15 to 333.15   K under atmosphere pressure. For the temperature range investigated, the solubility of HDCA in the solvents increased with increasing temperature. The modified Apelblat model, the Buchowski–Ksiazaczak λh model, and ideal model were adopted to describe and predict the change tendency of solubility. Besides, the calculated thermodynamic parameters indicated that in each studied solvent the dissolution process of HDCA is endothermic. Based on the analysis above, ethanol is considered to be the best solvent in crystallization process of HDCA.