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Updated: Jun 19, 2026
08:41
Generation and Control of Electrohydrodynamic Flows in Aqueous Electrolyte Solutions
Published on: September 7, 2018
ELECTRICAL FACTORS INFLUENCING THE RATE OF FILTRATION OF AQUEOUS ELECTROLYTE SOLUTIONS THROUGH CELLOPHANE MEMBRANES
H L White1, B Monaghan, F Urban
1Department of Physiology and the Department of Biological Chemistry, Washington University School of Medicine, St. Louis.
The Journal of General Physiology
|October 30, 2009
Summary
Electrokinetic factors influence membrane filtration rates. Higher electrokinetic potential inversely correlates with filtration rate, with maximum rates at the isoelectric point.
Area of Science:
- Physical Chemistry
- Membrane Science
- Colloid Science
Background:
- Electrokinetic phenomena significantly impact fluid transport across membranes.
- Understanding these effects is crucial for optimizing filtration processes.
Purpose of the Study:
- To investigate the influence of electrokinetic factors on the filtration rate of aqueous electrolyte solutions.
- To elucidate the relationship between electrokinetic potential and membrane filtration.
Main Methods:
- Comparative analysis of filtration rates using thorium chloride solutions at varying concentrations.
- Measurement of filtration rates across membranes at their isoelectric point and other conditions.
- Evaluation of electrokinetic potential and its correlation with filtration dynamics.
Main Results:
- Maximum filtration rate observed at the isoelectric concentration of the membrane.
- Filtration rate decreases as electrokinetic potential increases, indicating an inverse relationship.
- The study explored two potential mechanisms: stream potential-electroosmotic back-transport and electrical factor-induced pore diameter variation.
Conclusions:
- An inverse relationship exists between electrokinetic potential and membrane filtration rate.
- The precise contributions of proposed mechanisms remain difficult to quantify.
- Lepeschkin's membrane resistance is identified as an artifact, not a true property.
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