The influence of interparticle forces in the magnetic separation of submicron particles

The magnetic separation of ultrafine particles is described in terms of a number of particle - particle - fibre interactions some of which are important only in this size regime. Conditions for solid and diffuse buildup are established in terms of the total potential energy of a particle. The detailed form of the buildup is shown to be strongly dependent on the surface potential of particles and, consequently, the pH of the colloid. The calculated results are found to compare favourably with diffusion theory. The initial rate of particle capture is shown to be a quadratic function of time.