High pressure phase equilibria in methane + waxy systems 1. Methane + heptadecane

Fluid–fluid and fluid–solid phase equilibrium were experimentally determined under pressure on the system methane + heptadecane using a full isibility cell. Measurements were performed using the synthetic method on mixtures ranging from pure heptadecane to 99% of methane. The iquid–solid phase transitions were investigated up to 90 MPa and fluid phase boundary was studied in the temperature domain from 293 to 373 K. he appearance of a minimum in the three phase (V–L–S) equilibrium curve is discussed and it is shown that the difference in the solid phase tructure and the presence of a solid–solid phase transition do not affect significantly the phase diagram determined. 2007 Elsevier B.V. All rights reserved.