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

ABSTRACT

The solubility in supercritical carbon dioxide, at pressures from (10 to 50) MPa and temperatures from (40 to 60) ?C, is reported for two nonflavonoid, low molecular weight phenolic compounds, 4-hydroxy- 3,5-dimethoxybenzoic acid (syringic acid) and 4-hydroxy-3-methoxybenzoic acid (vanillic acid). Two types of models have been used for correlation of the experimental solubility data. First a rigorous thermodynamic method, with the Peng-Robinson equation of state, was used to determine the fugacity of the fluid phase. Second, two semiempirical density-dependent correlations were used: a linear correlation between the enhancement factor and the density of the solvent, as suggested by Schmitt and Reid, and the Chrastil correlation.