Monte Carlo Simulation for Vapor-Liquid Equilibrium of Binary Mixtures CO2/CH3OHCO2/C2H5OH, and CO2/CH3CH2CH2OH

Abstract

Gibbs ensemble Monte Carlo simulations were performed to calculate the vapor-liquid coexistence properties for the binary mixtures <TEX>$CO_2/CH_3OH$</TEX>, <TEX>$CO_2/C_2H_5OH$</TEX>, and <TEX>$CO_2/CH_3CH_2CH_2OH.$</TEX> The configurational bias Monte Carlo method was used in the simulation of alcohol. Density of the mixture, composition of the mixture, the pressure-composition diagram, and the radial distribution function were calculated at vapor-liquid equilibrium. The composition and the density of both vapor and liquid from simulation agree considerably well with the experimental values over a wide range of pressures. The radial distribution functions in the liquid mixtures show that <TEX>$CO_2$</TEX> molecules interact more stogly with methyl group than methylene group of <TEX>$C_2H_5OH$</TEX> and <TEX>$CH_3CH_2CH_2OH$</TEX> due to the steric effects of the alcohol molecules.