PREDICTION OF LIQUID-LIQUID EQUILIBRIA OF POLYMER-SALT AQUEOUS 2-PHASE SYSTEMS BY A MODIFIED PITZERS VIRIAL EQUATION

Citation
Yt. Wu et al., PREDICTION OF LIQUID-LIQUID EQUILIBRIA OF POLYMER-SALT AQUEOUS 2-PHASE SYSTEMS BY A MODIFIED PITZERS VIRIAL EQUATION, Fluid phase equilibria, 124(1-2), 1996, pp. 67-79
Citations number
24
Categorie Soggetti
Engineering, Chemical","Chemistry Physical
Journal title
ISSN journal
03783812
Volume
124
Issue
1-2
Year of publication
1996
Pages
67 - 79
Database
ISI
SICI code
0378-3812(1996)124:1-2<67:POLEOP>2.0.ZU;2-5
Abstract
A modified Fitter's virial equation, which combines the long-range ele ctrostatic contribution from Fowler and Guggenheim with the short-rang e virial equation, is presented for the excess Gibbs free energy of so me special kinds of systems. The model is used to predict the liquid-l iquid equilibrium (LLE) at 298.15 K of three polymer-uni-bivalent salt -aqueous two-phase systems: polyethylene glycol(PEG)-(NH4)(2)SO4, PEG- Na2SO4, PEG-Na2CO3 by correlating the parameters from the correspondin g vapor-liquid equilibrium (VLE) data. The results show that the model can give excellent representation of the VLE data of PEG solutions, e ither binary or ternary, the model parameters being independent of the chain lengths of the polymers. The comparison between the predicted a nd experimental phase diagrams shows that the suggested model has good prediction ability for PEG-uni-bivalent salt systems.