Fluid Phase Equilibria, Vol.260, No.2, 287-294, 2007
Solubility of disperse yellow 54 in supercritical carbon dioxide with or without cosolvent
Extraction of disperse yellow 54 with supercritical carbon dioxide was conducted at 393.2 K and 30 MPa over a wide range of contact times. Saturated solubilities of the disperse dyestuff in supercritical carbon dioxide with or without cosolvent were also measured over the temperature and pressure ranges of 353.2 K to 393.2 K and 15 MPa to 30 MPa. Either ethanol or dimethyl sulfoxide, up to 5 mol%, was used as a cosolvent. As evidenced from the experimental results, the magnitudes of equilibrium solubility can be effectively enhanced in the presence of both two cosolvents. Dimethyl sulfoxide was found to yield higher solubility enhancement. Cosolvent effects were discussed on the basis of the Kamlet-Taft solvatochromic solvent parameters of cosolvents. The saturated solubility data were correlated with the Chrastil and the Mendez-Santiago and Teja equations. The Chrastil model correlated the solubility data to about within the experimental uncertainty. The correlated results of the Mendez-Santiago-Teja model supported the consistency of the solubility data over the entire experimental conditions. (C) 2007 Elsevier B.V. All rights reserved.