Measurement and Modeling of Phase Equlibrium of Binary Systems, Carbon Dioxide-Toluene and Carbon Dioxide-Ethanol at High Pressures for Determination of Optimum Condition of Fine Particles Production in the Gas Anti-Solvent Process

In this research, high pressure vapor-liquid equilibrium apparatus built and the solubility of carbon dioxide in two organic solvents, toluene and ethanol, at temperature range 298.15-318.15 K and pressures up to 78 bar were measured. The obtained experimental data show that the solubility of carbon dioxide increases by increasing the pressure and decreases by increasing the temperature. The experimental data correlated by PR and SRK equation of states along with the van der Waals and Huron-Vidal mixing rules. The adjustable parameters and average absolute relative deviations of each model have been reported. The SRK-HV model with an average deviation of 2.52% for the carbon dioxide-toluene binary system at four temperatures and 3.79% for the carbon dioxide-ethanol system at three temperatures is the best between the studied models. Also the average deviation of SRK equation of state is 4.95% and the average deviation of PR equation of state, is 5.15% at all studied temperatures and pressures. The study of the relative volume expansions of toluene and ethanol show that 295.15 K and 57 bar are the best operating condition for gas anti-solvent process by using toluene and ethanol.