Solid-Vapor and Liquid-Vapor Phase Equilibria for the Helium-Krypton System

Abstract

A vapor-recirculation equilibrium cell was used to investigate both the solid-vapor and liquid-vapor equilibria and the three-phase curve for the system helium-krypton. Gas-phase compositions were measured above solid krypton at 100.00, 105.00, 110.00, and 115.00 K and at pressures to 1 20 atm (1 2.1 6 MN/m2).Both gas and liquid compositions were determined at 117.09, 120.85, 129.60, 139.56, and 150.00 K for the same range of pressures. Analysis of the gas-phase data by both the virial and modified Redlich-Kwong equations indicates that a deviation parameter of about 0.3 is necessary for the geometric-mean mixing rule for energy parameters. Comparison of the Henry's law constants for the liquid phase with the statistical model of Miller and Prausnitz indicates a somewhat larger deviation parameter.

Measurement and prediction of high‐pressure phase equilibria with a dilute component in the gas phase: The methane‐n‐hexane system

“…First three empirical plotting techniques provide the simplest procedures for binary mixtures. To check vapor phase accuracy, some investigators (Kidnay et al, 1971) use a plot of the enhancement factor versus the pressure difference ( P -P j O ) . The enhancement factor is defined as the heavy component partial pressure divided by its vapor pressure yjP/Pju.…”

Liquid‐vapor equilibria at 112.00 K for systems containing nitrogen, argon, and methane

“…The phase equilibria measurements were made in a closedloop, vapor recirculation system. Since the vapor-recirculation pump and the cryostat have been discussed in detail elsewhere (Hiza and Duncan, 1969;Duncan and Hiza, 1970) and fairly complete descriptions of the general experimental method have also been published (Kidnay et al, 1971;Miller et al, 1972), only those aspects of the measurements peculiar to the nitrogen-argon-methane system will be discussed here.…”