On Adsorption and Diffusion in Porous Media
- Albers, Bettina
2010 Mathematics Subject Classification
- 76S05 73Q05 73S10
- Adsorption, diffusion, flows in porous and granular materials
The paper contains a macroscopic continuum model of adsorption in porous materials consisting of three components. We consider the flow of a fluid/adsorbate mixture through channels of a solid component. The fluid serves as carrier for an adsorbate whose mass balance equation contains a source term. This term consists of two parts: first a Langmuir contribution which is connected with bare sites on internal surfaces and describes the Langmuir isotherm in equilibrium. The second one is due to changes of the internal surface driven by the source of porosity which is a part of the balance equation for porosity. We clearly state the range of applicability of the model. A simple numerical example which describes the transport of pollutants in soils illustrates the coupling of adsorption and diffusion. The results show that after a certain time arises a maximum in the rate of adsorption as a function of fluid/adsorbate velocity.
- On Adsorption and Diffusion in Porous Media. ZAMM 81 (2001) 10, 683-690