Non-linear electrophoresis of ideally polarizable particles

Abstract

This thesis investigates the non-linear regime of electrophoresis, in particular the variation of electrophoretic velocity with electric field at high field strengths. Known theoretical approaches to the problem accounting for ion steric effects, dielectric decrement effects and charge-induced thickening are consolidated, further developed and validated using numerical simulations. In doing so, the influences of the relative strengths of surface conductivity and bulk conductivity and of the relative importance of advection to diffusive transport in the electrolyte are both investigated. In addition, further light is shed on the dependence of electrophoretic mobility on the ionic and particle sizes, and on the relevant ionic diffusivities.