High-pressure phase equilibria for the carbon dioxide–2-pentanol and carbon dioxide–water–2-pentanol systems

Abstract

High pressure vapor–liquid equilibria for the binary carbon dioxide–2-pentanol system are measured at 313.2 K. The phase equilibrium apparatus used in this work is of the circulation type in which the coexisting phases are recirculated, on-line sampled, and analyzed. The critical pressure and corresponding mole fraction of carbon dioxide at 313.2 K are found to be 8.67 MPa and 0.985, respectively, for this binary system. The phase equilibria for the ternary carbon dioxide–water–2-pentanol system are also measured at 313.2 K and at pressures of 2.0, 4.0, 6.0, 8.0, and 8.64 MPa. The ternary carbon dioxide–2-pentanol–water systems show three LLV phases over the range of pressure up to 8.64 MPa. The binary experimental equilibrium data are correlated with the Redlich–Kwong, Soave–Redlich–Kwong, Peng–Robinson, and Patel–Teja equations of state with two different mixing rules, the van der Waals and the Panagiotopoulos–Reid mixing rules. The binary experimental data are well correlated by using three equations of state and corresponding mixing rules.