and their mixtures at various mass ratio were measured isovolumetrically at temperature of 308.15-328.15 K and pressure of 0-3 MPa. Effect of[Bmim] [NTf2] on DEC vapor pressure was studied using COSMO-RS model. The experimental results showed that CO2 solubility in DEC and[Bmim] [NTf2] increased with increasing pressure at constant temperature but decreased with increasing temperature at constant pressure. CO2 solubility in DEC was lower than that in[Bmim] [NTf2] under same conditions
which could be enhanced by adding[Bmim] [NTf2] to DEC. CO2 solubility in mixture of[Bmim] [NTf2] and DEC increased with increasing mass ratio of[Bmim] [NTf2] at constant temperature while CO2 solubility in mixtures of constant mass ratios decreased with increasing temperature. COSMO-RS simulation showed that percentage of DEC vapor pressure drop increased with increasing mass ratio of[Bmim] [NTf2] whereas DEC vapor pressure changed a little at temperature of 308.15-328.15 K for mixtures of same mass ratio.