Thermochemical investigations of associated solutions: 5. Calculation of solute-solvent equilibrium constants from solubility in mixtures containing two complexing solvents.
Solubilities are reported for carbazole in binary dibutyl ether plus 1-chlorohexane mixtures at 25 degrees C. Results of these measurements are compared with solution models developed for solubility in systems containing specific solute-solvent interactions. A simple stoichiometric complexation model based on a 1:1 carbazole:dibutyl ether complex could describe the measured solubility to within an average absolute deviation of 1.7%. The calculated equilibrium constant, though, was about one-half of values previously determined from carbazole solubilities in several binary dibutyl ether plus alkane mixtures. A more sophisticated solution model, derived by assuming both 1:1 carbazole: dibutyl ether and carbazole:chlorohexane complexes, could describe the solubilities to within 2.4%. This latter model enables the carbazole-chlorohexane association constant to be calculated from experimental carbazole solubilities and a priori knowledge of the carbazole-dibutyl ether equilibrium constant.
Acree
W E
WE
Department of Chemistry, Kent State University, OH 44242.
McCargar
J W
JW
D002227:Carbazoles; D004987:Ethers; D006586:Hexanes; D006843:Hydrocarbons, Chlorinated; D008956:Models, Chemical; D008962:Models, Theoretical; D012995:Solubility; D012996:Solutions; D012997:Solvents; D013816:Thermodynamics
D002227:Carbazoles; D004987:Ethers; D006586:Hexanes; D006843:Hydrocarbons, Chlorinated; D012996:Solutions; D012997:Solvents; C041514:carbazole; C053284:dibutyl ether; C053283:1-chlorohexane