Carbon dioxide‐ethane phase equilibrium and densities from experimental measurements and the B‐W‐R equation

Abstract
Liquid composition‐total pressure and liquid composition‐liquid density data for the carbon dioxide‐ethane system were measured at −31.7°, −17.8°, −3.9°, and 10.0°C (−25°, 0°, 25°, and 50°F ± 0.02°F), from 0 to 80 mole % CO2 at 10°C and 0 to 100% CO2 for the other isotherms. The Benedict‐Webb‐Rubin equation of state with a modified A0 mixing rule was used to correlate the composition‐pressure data, with deviations in predicted pressures of only 0.8% average and 2% maximum. Vapor‐liquid equilibrium compositions and component K values y/x were then predicted for this minimum boiling azeotrope system from 10° down to −56.7°C (50° to −70°F).