Definition - What does Electrokinetic Potential mean?
Electrokinetic potential refers to a potential difference in a liquid characterizing electrochemical equilibrium on interfaces. This potential difference is the result of a residual, unbalanced charge distribution in the adjoining liquid, which produces a double layer. This potential depends on the properties of a liquid and the properties of the surface. It has a significant role in the theory of aggregative stability.
Electrokinetic potential is a prime indicator in the stability of colloidal dispersions. From the magnitude of this potential, the degree of electrostatic repulsion between similarly charged adjacent particles in the dispersion can be determined.
Electrokinetic potential is also known as zeta potential.
Corrosionpedia explains Electrokinetic Potential
Electrokinetic potential is a potential difference at the boundary between the compact layer and the diffuse layer near a solid-liquid interface where liquid velocity is zero. It is a very important interfacial property for a large number of natural phenomena, for example electrode kinetics, electrocatalysis, corrosion, adsorption and colloidal stability. The electrokinetic potential is not same as the electrode potential as it occurs solely in the solution phase.
Electrokinetic potential property is exhibited by any particle in suspension. Electrostatic repulsion between particles depends on the value of this potential. The higher the value of electrokinetic potential the stronger the repulsion; therefore the system is more stable.
Electrokinetic or zeta potential measurements are very common to use in the following fields:
- Clay technology - Soil treatment, oil well drilling and ceramics.
- Water purification and industrial waste - Zeta potential measurements indicate the optimum coagulation condition for removal of particulate matter and organic dyestuffs from wastewater.
- Minerals and ore flotation - Low zeta potential indicates little adsorption (anionic or cationic) and flotation recovery.
- Emulsions - Zeta potential is used to optimize the formulation of suspensions and emulsions.
- Detergency - Dirt redeposition is governed by the influence of detergent adsorption and the zeta potential of both the dirt particles and the fabric's surface.
- Paints - Zeta potential measurements are useful in the control of storage, stability and behavior during application and drying.
- Electro-deposition - Electrophoretic mobility measurements are valuable in establishing the optimum pigment dispersion with various additives.
- Purification - Proper zeta potential is required for maximum removal of impurities and optimum conditions for rapid sedimentation.