Measurement of isothermal (vapor+liquid) equilibria, (VLE) for binary (CH₄+CO₂) from T=(240.35 to 293.15) K and CO₂ rich synthetic natural gas systems from T=(248.15 to 279.15) K

Isothermal vapor-liquid equilibrium (VLE) data for methane (CH<inf>4</inf>)+carbon dioxide (CO<inf>2</inf>) binary system at temperature range of (240.35-293.15) K and synthetic carbon dioxide rich natural gas mixtures at temperature and pressure range of (248.15-279.15) K and (2.81-9.05) MPa were measured in sapphire type equilibrium cell apparatus. Thermodynamic modeling of experimental data was carried out with GERG2008-equation of state (EOS) and volume-translated Peng-Robinson equation of state (VTPR-EOS) using van der Waals (vdw1) mixing rule. For CH<inf>4</inf>+CO<inf>2</inf> system, the temperature dependent binary interaction parameters (kij) were tuned to measured VLE data, whereas, between CO<inf>2</inf> with other hydrocarbons the value of kij = 0 was assumed. Comparison between measured and prediction shows excellent agreement with overall lower deviations were obtained.