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Updated: Jun 15, 2026
08:41
Generation and Control of Electrohydrodynamic Flows in Aqueous Electrolyte Solutions
Published on: September 7, 2018
Electro-osmosis in kaolinite with pH-dependent surface charge modelling by homogenization
Sidarta A Lima1, Marcio A Murad, Christian Moyne
1Laboratório Nacional de Computação Científica LNCC/MCT, Av. Getúlio Vargas 333, Petrópolis, RJ, Brazil. sidarta@lncc.br
Anais Da Academia Brasileira De Ciencias
|March 9, 2010
Summary
A novel three-scale model simulates ion transport and pH-dependent flow in kaolinite clays, incorporating adsorption. This model aids in understanding and simulating soil decontamination processes like electrokinetics.
Area of Science:
- Environmental Engineering
- Geochemistry
- Physical Chemistry
Background:
- Kaolinite clays exhibit complex behavior due to pH-dependent flows and ion transport.
- Understanding ion adsorption and electrical double layer effects is crucial for soil remediation.
Purpose of the Study:
- To develop a three-scale model coupling pH-dependent flows and transient ion transport in kaolinite.
- To incorporate adsorption phenomena and electrical double layer influences into a macroscopic model.
- To simulate soil decontamination using electrokinetic processes.
Main Methods:
- A three-scale model integrating nano/micro and macroscopic levels.
- Application of Nernst-Planck equations for ion movement and Helmholtz-Smoluchowski condition for flow.
- Homogenization of the nano/micro model to the Darcy scale.
- Discretization using the finite volume method for simulation.
Main Results:
- A constitutive law for the effective partition coefficient governing sodium adsorption was derived.
- The model successfully simulated the desalination of a kaolinite sample via electrokinetics.
- The coupling between flow, ion transport, and adsorption was effectively captured.
Conclusions:
- The proposed three-scale model provides a robust framework for analyzing complex phenomena in kaolinite clays.
- The model demonstrates feasibility for simulating soil decontamination processes.
- This approach enhances the understanding of ion transport and adsorption in clay systems.
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