Measurement And Correlation Of Solubilities Of Disperse Red 54 In Supercritical Carbon Dioxide With Cosolvent

Supercritical carbon dioxide dyeing has been received widely attention, which reduce wastewater discharge and consumption of energy, need less time with desired dyeing effect. The solubilities of disperse dyes in supercritical CO₂ are important to the foundational research and technologic development of supercritical fluid dyeing. Adding a cosolvent into supercritical CO₂ dyeing system is expected to enhance the dye solubility, which is significant to improve the dyeing speed or reduce the pressure of supercritical CO₂ dyeing.The solubilities of C.I. Disperse Red 54 in supercritical CO₂ were measured at temperatures from 343.2 to 403.2 K, pressures from 10 to 26 MPa and solubilities in supercritical CO₂ with different cosolvent such as ethanol (1%, 2%, 3%), water (1%, 2%, 3%) or acetone (1%) were measured at temperatures from 343.2 to 383.2 K by a static recirculation method. C.I. Disperse Red 54 was easy to dissolve in supercritical CO₂, and the solubilities values were from 0.72×10^-5 to 9.90×10^-5 in mol/mol. When contents of ethanol, water and acetone were 1%, solubilities of C.I. Disperse Red 54 in supercritical CO₂/cosolvent were 1.34×10^-511.44×10^-5, 1.10×10^-510.99×10^-5 and 2.41×10^-511.39×10^-5 in mol/mol, respectively. While contents of ethanol and water were 2%, solubilities of C.I. Disperse Red 54 in supercritical CO₂/cosolvent were up to 1.93×10^-512.83×10^-5 and 1.24×10^-512.57×10^-5, respectively. When contents of ethanol and water were 3%, solubilities of C.I. Disperse Red 54 in supercritical CO₂/cosolvent were up to 2.80×10^-514.38×10^-5 and 1.42×10^-513.98×10^-5 in mol/mol, respectively. Under the experimental conditions (with or without cosolvent), solubilities of C.I. Disperse Red 54 increased with the temperature and pressure increased. Solubilities of C.I. Disperse Red 54 in supercritical CO₂/cosolvent increased with contents of cosolvent in a non-linear trend. The solubilities of C.I. Disperse Red 54 in supercritical CO₂/cosolvent were not proportional to polarity of cosolvent. The cosolvent effect to solubilities of C.I. Disperse Red 54 in supercritical CO₂ was in the order of acetone > ethanol > water.Correlation results of solubilities in supercritical CO₂ with the Chrastil and MT model were 6.92% and 15.53%, respectively. Correlation results of solubilities in supercritical CO₂/cosolvent with M-Chrastil and MMT model were 6.21%⁶.43% and 11.05%¹3.07%, respectively. The correlation results showed that Chrastil model was more precise than MT model.