Thermodynamics Research Center / ThermoML | Journal of Chemical and Engineering Data

ABSTRACT

The equilibrium solubility of palmatine in various mixed solvents consisting of ethanol (ethylene glycol (EG), isopropanol and propylene glycol (PG)) plus water was experimentally obtained by static technology with the environment conditions (283.15-328.15 K, 101.1 kPa). The measured data of palmatine had a proportional relationship with temperature under the condition of fixed solvent composition, the same as increasing with the increasing the co-solvents of ethanol and EG except for the isopropanol and PG in four binary systems. The maximum solubility (0.01339 in mole fraction at 328.15 K) of palmatine was obtained in neat ethanol. Under the same solvent composition and regular temperature, palmatine was most soluble in a mixture of ethanol + water among all binary systems. XRPD and DSC were employed to analyze palmatine, which showed that no significant changed in the crystals before and after recrystallization. Three co-solvency models - the Jouyban-Acree model, van't Hoff-Jouyban-Acree model and Apelblat-Jouyban-Acree model were employed to correlate the measured data. In all calculation results, the largest RAD and RMSD were 1.44x10-2 and 5.10x10-5.