(181ap) Volumetric Properties for the Carbon Dioxide + Heptane + Dodecane

This work reports (P, r, T, xi) measurements in the compressed fluid phase for the ternary system carbon dioxide – heptane – dodecane in the (313 to 363) K temperature range and at pressures up to 25 MPa. The obtained data were measured by means of a static-synthetic method based apparatus which couples a feeding cell with an Anton Paar vibrating tube densimeter reported in previous papers. Measurements were performed with an estimated uncertainty,  to be less than ±0.01 MPa for pressure, ±0.03 K for temperature and ±0.001 for . Obtained data were correlated with the five-parameter Modified Toscani Swarcz equation to represent the behavior of this mixture. Derived thermodynamic properties (isobaric expansivity, isothermal compressibility, thermal pressure coefficient and internal pressure) were also calculated by using the parameters of the equation above mentioned. PrT properties for this ternary system have not been reported in open literature before this work. Experimental data obtained form part of a major study about vapor-liquid equilibria, densities and solubility of n-alkanes with or in carbon dioxide.