Document Type : Regular Article


1 Department of Chemical Engineering, South Tehran Branch, Islamic Azad University, Tehran, Iran.

2 Department of Chemical Engineering, Marvdasht Branch, Islamic Azad University, Marvdasht, Iran



One of the methods to reduce particle size is the GAS method. In this method, solute and antisolvent should be dissolved well in a solvent. But solute is not dissolved in a solvent. The aim of this modeling study is to determine the phase equilibrium and thermodynamic conditions of (CO2, solvent, 5-Fluorouracil) in the GAS process. The solvents include methanol, ethanol, acetone, 1-propanol, and 1-butanol. Peng-Robinson equation of state with a linear combination of Vidal and Michelsen mixing rules (PR-LCVM) was used for thermodynamic modeling. The volume expansion of the binary system (CO2, solvent) and ternary system (CO2, solvent, 5-Fluorouracil) at the temperature ranges of 313.15–319.15 K were investigated. The Pmin for the binary system was 66.7, 69.6, 60, 73.7, and 76.8 bar for methanol, ethanol, acetone, 1-propanol, and 1-butanol at 313.15 K, respectively. The Pmin for the ternary system was also calculated. The comparison between the binary and ternary system values showed that for a constant temperature and a certain solvent, the calculated minimum pressure in the ternary system was greater than in the binary system.