Conductivity of a concentrated spherical colloidal dispersion
Journal
Journal of Physical Chemistry B
Journal Volume
105
Journal Issue
4
Pages
747-753
Date Issued
2001
Author(s)
Abstract
The conductivity of a concentrated suspension of charged spherical particles at an arbitrary level of surface potential is estimated. The cell model proposed by Kuwabara is adopted to simulate the present many-body problem by taking the effect of double-layer polarization into account. Several interesting results are found which cannot be observed if the corresponding linearized model is considered. For example, if £p r has a medium value, (K*/K ¡Û) has a local minimum as Ka varies, £p r K*, K ¡Û, £e, and a being respectively the scaled surface potential, the effective conductivity, the effective conductivity for an infinitely dilute dispersion, the reciprocal Debye length, and the radius of a particle. For both £ea¡÷0 and £ea ¡÷ ¡Û (K*/K ¡Û) decreases with the increase in the volume fraction of the dispersed phase, and the reverse is true for a medium £ea. For a fixed £ea, the variation of (K*/K ¡Û) as a function of £p r may have a local minimum as £\ (=valence of counterions/ valence of co-ions) varies. For a fixed £p r, the variation of (K*/K ¡Û) as a function of £ea may have a local minimum as a varies. ? 2001 American Chemical Society.
Type
journal article