Solid-liquid equilibrium solubility, thermodynamic properties, solvent effect of Ipriflavone in twelve pure solvents at various temperatures

Abstract

In this study, by using laser dynamic monitoring, the dissolution behavior of ipriflavone (IP) in pure solvents of methanol, ethanol, n-propanol, n-butyl alcohol, 1-pentanol, methyl acetate, DMF, DMAC, acetone, acetonitrile, methylbenzene at (278.15–323.15) K and dichloromethane at (278.15–308.15) K was investigated under 0.1 MPa. The results showed that the molar solubility of IP in pure solvents increases non-linearly with the increase of the experimental temperature. The order of the solubility of IP in the pure solvents studied is: dichloromethane > DMAC > DMF > methylbenzene > methyl acetate > acetone > acetonitrile > 1-pentanol > n-butyl alcohol > n-propanol > ethanol > methanol. Moreover, experimental solubility data were correlated well with five thermodynamic models (Apelblat, λH, NRTL, UNIQUAC, and Van't hoff model). The calculation results showed that the Apelblat model has the smallest average values of the relative deviation (ARD) and root mean square deviation (104RMSD), being 1.878% and 2.933, respectively. Furthermore, the influence of solvent–solute interactions on the solubility of IP in pure solvents was analyzed by using the KAT-LSER model. In addition, the apparent thermodynamic properties(△solG°, △solH°, △solS°) of IP in pure solvents were calculated by correlating experimental solubility data with the Van't hoff model. The results show that the dissolution process of IP in the experimental solvents was endothermic and entropy-driven.