Premium
Volumetric properties of supercritical ethanen‐ n ‐heptane mixtures: The isothermal compressibility in the critical region
Author(s) -
Ehrlich P.,
Wu P. C.
Publication year - 1973
Publication title -
aiche journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.958
H-Index - 167
eISSN - 1547-5905
pISSN - 0001-1541
DOI - 10.1002/aic.690190319
Subject(s) - compressibility , supercritical fluid , thermodynamics , isothermal process , heptane , equation of state , locus (genetics) , chemistry , physics , biochemistry , gene
The isothermal compressibility (at constant composition x ) k T, x , was calculated in the neighborhood of the critical locus for seven mixtures containing 3.5 to 19.6 mole % heptane and analyzed in terms of the reduced pressure variable σ = ( P – P̂)/P̂ where P̂ is the pressure at which k T, x becomes very large. The data can be represented by the equation k T, x = const. σ −λ along the critical isotherm and one near it and by the locus P̂( T ). λ was found to be a strong function of x . The divergence of the isothermal compressibility of the mixtures near the critical locus is in conflict with predictions from classical equations of state but in accordance with modern concepts of the critical region.