High-Pressure Phase Equilibria in the Binary System (Methane + 5-α-Cholestane)

Abstract

In this paper, experimental data on the phase behavior of the binary system (methane + 5-α-cholestane) are presented. Experiments were carried out according to the synthetic method. The temperature range investigated was from 320 K to 450 K. The pressures applied did not exceed 250 MPa. Vapor−liquid equilibria have been measured for 18 different mixtures. Additionally, the melting curve of pure 5-α-cholestane and the course of the three-phase curve (solid 5-α-cholestane + liquid + vapor) was determined. The second critical end point was located at a temperature T = (342.2 ± 0.5) K, a pressure p = (193.3 ± 0.4) MPa, and a mole fraction of 5-α-cholestane in the critical fluid phase x = 0.049 ± 0.004.

Modeling the Cloud Curves and the Solubility of Gases in Amorphous and Semicrystalline Polyethylene with the SAFT-VR Approach and Flory Theory of Crystallization

“…The fluid-phase behavior is qualitatively different for mixtures of polyethylene and methane. Mixtures of asymmetric hydrocarbons have been studied extensively by researchers in Delft, − who have beautifully mapped out the vapor, liquid, and solid phase behavior of these systems. Though the equilibria between fluid phases becomes metastable at lower temperatures with the formation of solids, de Loos and co-workers 99,101 have pointed out that the fluid-phase behavior for methane−alkanes can be classified as either type III or type IV depending on the asymmetry.…”