(181ad) Hydrocarbon Mixtures: Phase Behavior, Density, and Modeling with PC-SAFT and a Volume-Translated, Cubic Equation of State

Density and phase behavior information of normal, branched, cyclic, and aromatic hydrocarbons and their mixtures at different pressures and temperatures are needed for both industrial applications and modeling studies. In the petrochemical industry, density data on hydrocarbon mixtures with CO₂ and/or water at pressures in excess of 240 MPa and temperatures of 260°C are used for the design and optimization of processes related to the production of oil, condensate and natural gas from ultra-deep wells, and the sequestration of CO₂ in deep saline aquifers. In modeling studies, high-pressure and high-temperature hydrocarbon density data for pure-component hydrocarbons and their mixtures are used to test different equations of state (EOS). The present study reports experimental high-pressure, high-temperature phase behavior and density data for pure component and binary hydrocarbon mixtures.  The density data are modeled with the Peng-Robinson EOS (PR EOS), a modified Soave-Redlich-Kwong EOS that incorporates a high temperature, high pressure volume-translation (HTHP VT-SRK EOS), and the Perturbed Chain Statistical Associating Fluid Theory (PC-SAFT EOS).