Theoretical Analysis of Electrophoretic Phenomena of Fine Particles and Its Application to Classification
The behavior in electric field of fine particles present in aqueous solution was measured in order to apply to the classification of fine particles. The sample particles used are spherical polystyrene particles with the average diameter of 0.03 μm, 0.1 μm, 1.0 μm, 4.3 μm and 9.6 μm. Electrophoretic mobility and zeta potential of various particles are measured by an instrument based on the principle of the laser Doppler effect. The influence of temperature, electrolyte concentration on the electrophoretic mobility was investigated for various polystyrene particles.The electrophoretic mobility increases with increasing pH and temperature of suspensions. The measured electrophoretic mobilities are different from electrolyte concentration and particle size.The electrophoretic retardation effect and relaxation effect are considered to explain the behavior of fine particles in electric field by applying the electro kinetic theory of Wiersema et al. For all particle size, the electrophoretic mobility decreases rapidly in high concentration of KNO3 such as 0.1 mol/dm3 due to the compression of electric double layer.The forces acting the particles in electric field are considered to be electrical force, friction force and some other forces like relaxation effect and electrophoretic retardation effect which appear in ionic behavior. It is considered that the particle moving velocity depends on the particle size. When the particle size is less than 1μm, the velocity increases with increasing the particle size. On the other hand, the velocity deceases with increasing in particle size, when the particle size is larger than 1μm. This phenomenon is considered to be interesting from the viewpoint of classification for fine particles. We found that the electrophoretic mobility of 1.0μm particles is larger than that of 0. 1μm particles, and that it is possible to classify fine particles by using the difference of electrophoretic mobility by many experimental results. The phenomena can be explained by the forces acting the fine particles in the electric field. We can apply the behavior to classification of fine particles.
Electrophoresis Polystyrene Fine particle Electrolyte solution Classification
J. Shibata D. Yamashita M. Tateyama N. Murayama
Department of Chemical, Energy and Environmental Engineering, Kansai University, Osaka, Japan
国际会议
XXIV International Mineral Processing Congress(第24届国际矿物加工大会)
北京
英文
540-544
2008-09-24（万方平台首次上网日期，不代表论文的发表时间）