Solid–Liquid Equilibrium of d- and l-Tartaric Acid and Their Importance for Enantioseparation

Abstract

The solid–liquid phase equilibrium of d- and l-tartaric acid (TA) was investigated in this work. Based on the solubility data, the dissolution enthalpy and entropy of the monohydrate racemic tartaric acid (race-TA) and enantiomer were calculated using van't Hoff plots. Binary melting point phase diagrams of d- and l-TA and ternary phase diagrams of d-TA/water/l-TA were also described. The results show that TA exhibits a racemic compound behavior. Furthermore, the influence of temperature on the eutectic points between enantiomer and racemic compounds was investigated. Finally, the importance of solid–liquid equilibrium on the purification and separation of enantiomers was discussed.