Solubility modelling and solvent effect on solid-liquid equilibrium of 2,2-bis(hydroxymethyl)butyric acid at different temperatures

Abstract

In this work, the solid-liquid equilibrium of 2,2-bis(hydroxymethyl)butyric acid (DMBA) was investigated experimentally in various solvents: namely, ethylacetate, butylacetate, methyl isobutyl ketone, cyclopentyl methyl ether, toluene, gamma-butyrolactone and 1,4-dioxane over the temperature range (298.15 to 353.15) K. The experimental solubility data were correlated with the Apelblat equation, Buchowski–Książczak λh equation and NRTL model. Results showed that the mole fraction solubility of DMBA increased, as temperature increased. The Apelblat equation and NRTL model indicated a good correlation with the experimental solubility data and can be used to describe the solid-liquid equilibrium. Further, the apparent thermodynamic dissolution functions and thermodynamic functions of mixing were evaluated from the solubility data.