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The European Physical Journal E

, Volume 28, Issue 1, pp 27–45 | Cite as

Modeling phase behavior for quantifying micro-pervaporation experiments

  • M. Schindler
  • A. Ajdari
Regular Article

Abstract

We present a theoretical model for the evolution of mixture concentrations in a micro-pervaporation device, similar to those recently presented experimentally. The described device makes use of the pervaporation of water through a thin PDMS membrane to build up a solute concentration profile inside a long microfluidic channel. We simplify the evolution of this profile in binary mixtures to a one-dimensional model which comprises two concentration-dependent coefficients. The model then provides a link between directly accessible experimental observations, such as the widths of dense phases or their growth velocity, and the underlying chemical potentials and phenomenological coefficients. It shall thus be useful for quantifying the thermodynamic and dynamic properties of dilute and dense binary mixtures.

PACS

47.61.-k Micro- and nano- scale flow phenomena 64.75.-g Phase equilibria 82.60.Lf Thermodynamics of solutions 05.70.Ln Nonequilibrium and irreversible thermodynamics 

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Copyright information

© EDP Sciences, SIF, Springer-Verlag Berlin Heidelberg 2009

Authors and Affiliations

  1. 1.Laboratoire PCT, UMR “Gulliver” CNRS-ESPCI 7083Paris cedex 05France

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