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oai:figshare.com:article/34030260 2026-09-30T06:19:10Z category_915 category_272 category_873 category_46 category_734 category_106 portal_63 item_type_6 month_year_09_2026

Vapor–Liquid Equilibrium Measurements and Binary Interaction Parameter Regression for the Peng–Robinson Equation of State in R134a–CO₂ Mixtures at LNG Regasification Conditions Geonwoo Jeong (16666966) Younghoon Sohn (10125973) Yutaek Seo (1680319) Physical Sciences not elsewhere classified Environmental Sciences not elsewhere classified Chemical Sciences not elsewhere classified Immunology Biological Sciences not elsewhere classified Science Policy peng – robinson mixed heating medium liquefied natural gas 4 – 31 14439 × 10 regressed bip coefficients measured bubble point experimental data obtained ></ sub >(< >< sub >< temperature conditions relevant relevant temperature ranges regressed bip correlation literature vle data lng regasification conditions 2 </ sub r134a – co vle data point pressures data points ij </ uniform across results show lng regasification independent reference gc analysis change behavior 6 mol 36 %. This study experimentally measured bubble-point pressures and vapor–liquid equilibrium (VLE) vapor-phase compositions of R134a + CO₂ mixtures under low-temperature conditions relevant to liquefied natural gas (LNG) regasification. The measurements were conducted for R134a-rich mixtures containing 8.4–31.6 mol % CO₂ using a 30 mL isochoric equilibrium cell and GC analysis. The measured bubble point and VLE data were used to regress a temperature-dependent binary interaction parameter (BIP) correlation for the Peng–Robinson (PR) equation of state in the form <i>k</i>_<i>ij</i>(<i>T</i>) = <i>k</i>_<i>ij</i>⁽¹⁾ + <i>k</i>_<i>ij</i>⁽²⁾·<i>T</i> + <i>k</i>_<i>ij</i>⁽³⁾/<i>T</i>. The regression was performed using only the experimental data obtained in this work, while literature VLE data below 300 K were used as an independent reference for comparison. The regressed BIP coefficients were <i>k</i>_<i>ij</i>⁽¹⁾ = −1.09683, <i>k</i>_<i>ij</i>⁽²⁾ = 2.14439 × 10^–3 K^–1, and <i>k</i>_<i>ij</i>⁽³⁾ = 141.824 K. After applying the regressed BIP correlation, the average absolute relative deviation (AARD) decreased from 3.54% to 2.76% for the bubble point pressure data and from 2.35% to 1.99% for the VLE vapor-phase composition data measured in this work, although the improvement was not uniform across all compositions and data points. For the independent low-temperature literature VLE data, the AARD decreased from 5.33% to 1.36%. The regressed BIP correlation was further applied to an LNG regasification process simulation using an R134a + CO₂ mixed heating medium. The results show that the regressed PR EOS parameters provide experimentally supported thermodynamic inputs for modeling the phase-change behavior of R134a + CO₂ mixtures in LNG regasification-relevant temperature ranges. 2026-09-30T00:00:00Z Text Journal contribution 10.1021/cbe.6c00097.s001 https://figshare.com/articles/journal_contribution/Vapor_Liquid_Equilibrium_Measurements_and_Binary_Interaction_Parameter_Regression_for_the_Peng_Robinson_Equation_of_State_in_R134a_CO_sub_2_sub_Mixtures_at_LNG_Regasification_Conditions/34030260 CC BY-NC 4.0