Phase equilibria of carbon dioxide + 1-nonanol system at high pressures

Vapor–liquid–equilibria (VLE) and vapor–liquid–liquid equilibria (VLLE) data for the carbon dioxide + 1-nonanol system were measured at 303.15, 308.15, 313.15, 333.15, and 353.15 K. Phase behavior measurements were made in a high-pressure visual cell with variable volume, based on the static-analytic method. The pressure range under investigation was between 1.15 and 103.3 bar. The Soave–Redlich–Kwong (SRK) equation of state (EOS) coupled with both classical van der Waals and a Gibbs excess energy (GE) mixing rules was used in semi-predictive approaches, in order to represent the complex phase behavior (critical curve, liquid–liquid–vapor (LLV) line, isothermal VLE, LLE, and VLLE) of the system. The topology of phase behavior is correctly predicted.