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

ABSTRACT

The solubility values of 5-chloro-8-hydroxyquinoline and 5,7-dichloro-8-hydroxyquinoline in six pure solvents at temperature ranging from (283.15 to 323.15) K was determined by the isothermal saturation method. In the investigated temperature range, the values of 5-chloro-8-hydroxyquinoline are larger than that of 5,7-dichloro-8-hydroxyquinoline at all studied temperatures. They decrease according to the sequence of (N-methyl-2-pyrrolidone greater than N,N-dimethylformamide greater than 1,4-dioxane greater than ethyl acetate greater than toluene greater than acetonitrile). The determined solubility data were correlated using the modified Apelblat equation, Buchowski-Ksiazaczak h equation and NRTL model. The results of correlation indicated that the calculated and experimental values agreed very well. The maximum values of root-mean-square deviation (RMSD) and relative average deviation (RAD) were (14.8810-4 and 1.46% for 5-chloro-8-hydroxyquinoline) and (2.53 e10-4 and 2.56% for 5,7-dichloro-8-hydroxyquinoline) respectively. The calculation results of thermodynamic properties show that the process of dissolving is apparently not only spontaneous but also entropy-driving.