Interfacial Instabilities During Interphase Mass Transfer of Propionic Acid

Abstract

We present a numerical study of the transient two-dimensional solutal Marangoni convection which occurs at the interface of a two isothermal layers’ system made of two immiscible liquids. The solute is propionic acid and is transferred through the interface from the organic phase to the aqueous phase under gravity condition. The unsteady state of this interfacial convection problem is mathematically described by the Navier-Stokes and solute mass transfer equations in both phases. The Hele Shaw approximation was incorporated in these equations and the resulting equations were solved using the COMSOL Multiphysics software. The latter is based on the finite elements’ method. The results obtained are in good agreement with the experiments and suggest that the mass transfer rate is stronger when the acid diffusion and the instability occur together.