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

ABSTRACT

The solubility of reserpine in eight different green solvents, namely, water, ethanol, ethylene glycol (EG), ethyl acetate (EA), isopropanol (IPA), propylene glycol (PG), poly(ethylene glycol)-400 (PEG-400), and transcutol, was measured and correlated from (298.15 to 338.15) K using the shake flask method. The experimental solubilities were correlated with temperature-dependent Apelblat and ideal equations. For the Apelblat equation, the root-mean-square deviations (RMSD) and correlation coefficients (R2) were obtained as 0.005 to 0.053 and 0.9978 to 0.9999, respectively. For an ideal Apelblat equation, the RMSD and R2 were obtained as 0.005 to 0.018 and 0.9950 to 0.9990, respectively. The mole fraction solubility of reserpine was observed highest in PEG-400 (1.44*10 3 at 298.15 K) followed by transcutol, EG, PG, IPA, ethanol, and water from (298.15 to 338.15) K. However, the mass fraction solubility of reserpine was observed highest in EA (3.60*10 3 at 298.15 K). The dissolution enthalpy, Gibbs energy, and dissolution entropy were determined by van t Hoff and Krug analysis, and results showed endothermic and spontaneous dissolution of reserpine in all green solvents investigated.