Densities and Volumetric Characteristics of Binary System of CO2 + Decane from (303.15 to 353.15) K and Pressures up to 19 MPa

Abstract

Densities of CO2 + decane binary mixtures were measured by using the magnetic suspension balance (MSB) at different CO2 mole fractions, x1 = 0.2361, 0.4698, 0.7100, 0.7725, and 0.8690 with temperatures from (303.15 to 353.15) K and pressures from (8 to 19) MPa. Excess molar volumes were calculated from the density data. The experimental results revealed that the density of CO2 + decane mixtures increases with increasing pressure and decreases with increasing temperature. The density of mixtures increases with increasing CO2 concentration first and then decreases at higher CO2 concentration and higher temperature. A crossover phenomenon with compositions is observed, and the crossover pressure increases with temperature. The excess molar volumes of this mixture display more negative values with increasing temperature at 18 MPa and less negative values with increasing pressure at 313.15 K. Moreover, the mixture densities have been predicted with GERG-2008 and a modified Benedict–Webb–Rubin–Starling (BWRS) model. The validities of the two models have been tested by predicting density data in this work and comparing with previous literature.