Solubilities of disperse dyes of blue 79:1, red 82 and modified yellow 119 in supercritical carbon dioxide and nitrous oxide

Abstract

Dissolution of disperse blue 79:1, red 82, and modified yellow 119 with supercritical carbon dioxide and nitrous oxide was studied at 393.2 K and 30 MPa over a wide range of contact times. Equilibrium solubilities of the dyestuffs in the supercritical fluids were also measured at temperatures from 353.2 to 393.2 K and pressures up to 30 MPa. The solubilities were enhanced generally about 100-fold as pressure increasing from 15 to 30 MPa. Under the same equilibrium condition, the solubilities of the dyes in carbon dioxide followed the order of red 82>blue 79:1>modified yellow 119, and modified yellow 119 is more soluble in nitrous oxide than in carbon dioxide. The solubility data were correlated with the Chrastil, the Sung–Shim, and the Mendez-Santiago–Teja models. The Chrastil model correlated the solubility data to about within the experimental uncertainty. The correlated results of the Mendez-Santiago–Teja model endorsed the consistency of the solubility data over the entire experimental conditions.