Отправлено: 18.08.08 05:39. Заголовок: Electrokinetic phenomena in saturated compact clays

Electrokinetic phenomena in saturated compact clays
Journal of Colloid and Interface Science, Volume 297, Issue 1, 1 May 2006, Pages 353-364
M. Rosanne, M. Paszkuta, P.M. Adler

Abstract
The membrane potential, the pressure difference, and the concentration difference induced by an applied concentration gradient through samples of compact clay were measured as functions of sodium chloride concentration and of porosity. The results of some previous numerical predictions are recalled to be functions of a characteristic length scale which can be derived from conductivity and permeability. Generally, the experimental data were in agreement with these numerical predictions. Therefore, nondiagonal coupling coefficients can be derived with acceptable precision from the diagonal coefficients.
Article Outline
1. Introduction
2. Theoretical background
2.1. Analysis on the pore scale
2.2. Analysis on the macroscopic scale
2.2.1. General case where U(t)Ѓ‚0
2.2.2. Special case where U(t)=0
3. Experimental
3.1. Materials
3.2. Measurements
3.3. Ag/AgCl electrodes
3.3.1. Electrode potential
3.3.2. Electrode preparation and test
3.4. Membrane potential determination
4. Results and discussion
4.1. Experimental results
4.2. Transport coefficients
4.2.1. Analysis of ѓБ13 and ѓБ31
4.2.2. Analysis of ѓБ23 and ѓБ32
4.2.3. Analysis of ѓБ33
4.3. Discussion
4.3.1. The dispersion coefficient
4.3.2. The conversion efficiency
4.3.3. Comparison with the analytical predictions
5. Conclusion
References