A Dynamic Approach to Brownian Coagulation of Electrostatically Stabilized Colloid Particles. Diffusion Relaxation of the Adsorption Layer
✍ Scribed by S.Yu. Shulepov
- Publisher
- Elsevier Science
- Year
- 1997
- Tongue
- English
- Weight
- 215 KB
- Volume
- 189
- Category
- Article
- ISSN
- 0021-9797
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✦ Synopsis
situation is almost always somewhere between these two In this paper the dynamic aspects of colloid particle interaction model descriptions.
during Brownian coagulation are considered. The disequilibration In preceding paper (5) we developed a model which of double layers is due to incomplete relaxation of the adsorbed allows for a transient disequilibration of the double layer charge at the particle surface. Surface diffusion is investigated as during coagulation process. In that model the relaxation ina rate-determining process of the adsorption charge relaxation.
volves a variety of processes, however the slowest process
Influence of the relaxation process on the interaction between two
is the rate determining. The diffuse part of a double layer spherical particles is studied for small surface potentials. We paid is assumed to have always very low De, when related to the particular attention to the transition between the charge regulation adsorption layer (4, 6). The adsorption layer relaxation ow-(the complete equilibrium) interaction and the constant surface charge (the total disequilibration) regime. The criterion is derived, ing to sorption-desorption of potential determining ions was which shows when the standard DLVO potential corresponding to studied in (5). It was shown that the relaxation processes can the constant surface charge interaction, or to the charge regulation significantly alter the interaction between particles. More, if regime, is applicable. Also, calculations in the transition region these processes are relevant for the interaction, the stability between these two regimes have been carried out, and a rather ratio is rather independent of the particle size, which is what simple approximate expression for the pair interaction potential is actually found in many experiments and cannot be exis derived. Consequences of the dynamic approach for the colloid plained by the standard theory. However, the relaxation stability problem are discussed.