Diffusion of Colloidal Fluids in Random Porous Media

Abstract

A simple manner to describe the diffusive relaxation of a colloidal fluid adsorbed in a porous medium is to model the porous medium as a set of spherical particles fixed in space at random positions with prescribed statistical structural properties. Within this model one may describe the relaxation of concentration fluctuations of the adsorbed fluid by simply setting to zero the short-time mobility of one species (the porous matrix) in a theory of the dynamics of equilibrium colloidal mixtures, or by extending such dynamic theory to explicitly consider the porous matrix as a random external field. Here we consider the first approach and employ the self-consistent generalized Langevin equation (SCGLE) theory of the dynamics of equilibrium colloidal mixtures, to describe the dynamics of the mobile component. We conclude that if the correct static structure factors are provided as input, the SCGLE theory correctly predicts the main features of the dynamics of the permeating fluid.

10 pages, 2 figures

References in corpus (4)

• Liquid-glass transition of a fluid confined in a disordered porous matrix: A mode-coupling theory
• Mode-coupling theory for the slow collective dynamics of fluids adsorbed in disordered porous media
• Simplified Self-Consistent Theory of Colloid Dynamics
• Capillary Condensation and Interface Structure of a Model Colloid-Polymer Mixture in a Porous Medium

Cited by in corpus (6)

• Tagged-particle dynamics in a fluid adsorbed in a disordered porous solid: interplay between the diffusion-localization and liquid-glass transitions
• Mode-coupling theory predictions for the dynamical transitions of the partly pinned fluid systems
• Impact of random obstacles on the dynamics of a dense colloidal fluid
• Statistical mechanics of homogeneous partly pinned fluid systems
• Simple physics of the partly pinned fluid systems
• Coalescing Clusters Unveil New Regimes of Frictional Fluid Mechanics