Premium
Fickian diffusion in binary mixtures that form two liquid phases
Author(s) -
Pertler Manfred,
Blass Eckhart,
Stevens Geoffrey W.
Publication year - 1996
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.690420403
Subject(s) - diffusion , thermodynamics , binary number , viscosity , miscibility , chemistry , constant (computer programming) , fick's laws of diffusion , spinodal decomposition , binary system , diffusion equation , effective diffusion coefficient , phase (matter) , physics , mathematics , organic chemistry , polymer , arithmetic , medicine , service (business) , economy , radiology , computer science , magnetic resonance imaging , economics , programming language
Abstract New data on the variation of the diffusion coefficient with concentration in binary nonideal liquid mixtures are presented. The diffusion coefficients were measured with laser holography with an improved analysis procedure and are primarily in systems that form two liquid phases. The results show that for such systems the diffusion coefficient is constant if a chemical‐potential driving force is used. If, however, the miscibility gap is wide, the Schreiner equation (Schreiner, 1922) is shown to be more accurate than relations that consider the variation of viscosity. Cluster theories developed for diffusion behavior near critical points were found to explain the data well only in water‐organic systems on the water‐rich side.