Isothermal vapor-liquid equilibria for binary mixtures of carbon dioxide with hexyl acetate, cyclohexyl acetate, or phenyl acetate at elevated pressures

Isothermal vapor-liquid equilibrium phase compositions were measured for th ree binary systems of carbon dioxide with different C6-acetates-hexyl aceta te, cyclohexyl acetate, and phenyl acetate-at temperatures from 333.15 K to 413.15 K and pressures up to 20 MPa. The solubility isotherm of the acetat es in the vapor phase exhibits a minimum value at subcritical pressures of carbon dioxide. Henry's constants were calculated by fitting the Krichevsky -Ilinskaya equation to the isothermal equilibrium data. The constants incre ase with increasing temperature for these three binary systems. The new pha se equilibrium data were correlated with the Soave-Redlich-Kwong, the Peng- Robinson, and the Patel-Teja equations of state. The Peng-Robinson equation with two-parameter (k(a12) and k(b12)) van der Waals mixing rules is margi nally better than other methods for the investigated systems.