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

ABSTRACT

The solubility of 9H-carbazole in sub- and supercritical propane has been measured using a static view cell at pressures from (4.3 to 10.0) MPa and temperatures from (323 to 405) K. The mole fraction of 9H-carbazole varied from 4*10-5 to 4*10-4 over the experimental range studied. The solubility of 9H-carbazole in propane is 1 order of magnitude higher than that of 9H-carbazole in CO2 for similar values of the reduced pressure and temperature, which highlights the excellent solvent properties of propane relative to CO2 for the extraction of polyaromatic compounds. The experimental solubility data were correlated with the Peng-Robinson equation of state using six different sets of mixing rules for the estimation of the mixture parameters aM and bM. Good fits of the experimental results were obtained for all of the mixing rules tested, especially for those involving two adjustable parameters; the absolute average percentage deviation (AAPD) was 16.4 % for the best fit. In addition, the empirical equation of Chrastil was used to model the experimental solubility, and a similar AAPD (16.6 %) was obtained. In this case, because of the simplicity of the empirical model, three adjustable parameters were required for the adjustment. Both of the mathematical expressions evaluated (Peng-Robinson and Chrastil) can be used for the prediction of the solubility of 9H-carbazole in propane.