(222t) Experimental Vapor-Liquid Equilibria for Carbon Dioxide + 1-Propanol + Heptane

The aim of this work is to report the vapor-liquid equilibrium (VLE) for the ternary system carbon dioxide + 1-propanol + heptane at temperatures of (315, 344 and 374) K. Experiments were performed in an apparatus based on the static – analytic method. The main advantages of the apparatus are the on-line sampling via a ROLSI sampler-injector and the volume sample of about 1 uL on each analysis. VLE is reported for temperature, pressure and compositions with an uncertainty less than 0.02 K, 0.008 MPa, 0.0035 for liquid and 0.0015 for vapor composition in mole fraction for the last two values. Separation factors obtained from experimental x_i, y_i mole fractions for heptane over 1-propanol indicate that heptane is feasible to be separated from 2-propanol in the presence of carbon dioxide. The higher values for this variable are obtained at 315 K, and as temperature rises, the separation factors decrease. In consequence, the lower values correspond to the temperature of 374 K. Finally, the experimental data of VLE were represented using the Peng-Robinson Equation of State with the classical and Wong-Sandler mixing rules. The binary interaction parameters were taken from data reported in the literature about VLE of the concerning binary systems.