TITLE: Relationship between the Carbon-Number of N-Paraffins and Their Solubility in Supercritical Solvents.

AUTHOR: C. J. Peters; J. de Swaan Arons; A. H. Harvey; J. M. H. Levelt Sengers.

INST.  AUTHOR: National Inst. of Standards and Technology (NEL), Gaithersburg, MD. Thermophysics Div.


PUB.  TYPE: Technical Report

PUB.  COUNTRY: United States

SOURCE: Department of Commerce [COMNBS],  1989,  8p.



A relationship is postulated between the solubility of liquid n-paraffins in supercritical solvents, such as methane and carbon dioxide, and the carbon number of the solute. The predictions of the simplified perturbed-hard-chain equation of state suggest that, at fixed temperature and pressure, the logarithm of the mole fraction of the solute varies linearly with the carbon number. A relation of this type is very useful for predicting supercritical solubility of long n-alkanes and retrograde condensation of natural gas. The thermodynamic considerations that lend support to the hypothesis are presented and agreement with available experimental data is shown.