VOLUME EXPANSION COEFFICIENTS AND ACTIVITY-COEFFICIENTS OF HIGH-PRESSURE CARBON-DIOXIDE DISSOLUTION IN ORGANIC LIQUIDS AT 298-K

The isothermal volume expansion coefficient and the liquid-phase composition of carbon dioxide dissolution in toluene, cyclohexanone, and butanol respectively at 298 K were measured using the high-pressure densitometer method with a liquid recirculating apparatus over a pressure range from 0.1 to 10 MPa. The solvent expansion behavior (expressed by the volume expansion coefficient) caused by the dissolution of carbon dioxide into the solvent was found to increase with the increase of pressure. The carbon dioxide-cyclohexanone system has the highest volume expansion coefficient in the range of pressure investigated. Experimental results obtained are analyzed by a thermodynamic procedure, and the nonidealities of vapor and liquid phases (i.e., fugacity coefficient and activity coefficient) are compared among these three systems.