Wanjun Kong, Rui Sun, Yanjuan Gao
Aug 5, 2015
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Influential Citations
8
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Journal
Journal of Chemical & Engineering Data
Abstract
The dissociation constants (pKa) of dalbergin and nordalbergin were measured at 298.2 K using ultraviolet (UV) spectroscopy method. The solubilities of dalbergin and nordalbergin in water, methanol, propanone, ethyl ethanoate, trichloromethane, and hexane have been determined by the UV spectrophotometric method from 283.2 to 308.2 K at atmospheric pressure. The experimental solubility values were correlated with a modified Apelblat equation, λh model, and ideal model. The pKa value of dalbergin is 8.91 ± 0.12, and the pKa1 and pKa2 values of nordalbergin are 7.31 ± 0.29 and 9.79 ± 0.39, respectively. The solubilities of dalbergin and nordalbergin in six solvents increase with an increase in temperature. The solubility order of dalbergin in six pure solvents was trichloromethane > propanone > ethyl ethanoate > methanol > hexane > water, whereas that of nordalbergin was propanone > methanol > ethyl ethanoate > trichloromethane > water > hexane. A comparison of the solubility of dalbergin with that of nordal...