Dye solubility in supercritical carbon dioxide. Effect of hydrogen bondingwith cosolvents

The use of supercritical carbon dioxide is emerging as a potential method f or achieving pollution- free dyeing. An important factor in supercritical f luid dyeing is the solubility of the dye in supercritical carbon dioxide. O ur measurements show that the solubility of C. I. Disperse Red-60 dye in su percritical carbon dioxide is significantly enhanced upon addition of polar cosolvents: ethanol and acetone. The solubility enhancement is attributed to the formation of hydrogen bonds between cosolvent and dye molecules. Obs erved solubility behavior is correlated using dilute-solution theory with l attice-fluid-hydrogen-bonding model. Needed physical and hydrogen-bonding m olecular parameters are estimated using the experimental data.