EFFECT OF NATURE OF IONS ON ELECTROPHORETIC MOBILITY OF MODEL PARTICLES

The electrophoretic mobilities of a colloid model of solidified emulsion particles (1) have been studied as a function of the concentration of KCl, Ba(ClO4)2, La(ClO4)3, LiCl, RbCl and KI. The zeta potentials have been calculated from these data. The surface potentials of spread monolayers of stearic acid have been measured as a function of the concentration of LiCl, KCl and RbCl; the corresponding monolayer potentials were calculated. The results obtained with this model are compared with those obtained with the models of Schenkel and Kitchener (2) and of Johnson, Goldfarb and Pethica (3). As it is found that the electrophoretic mobilities are highly dependent on the nature of counter ions, an attempt is made to explain this phenomenon in terms of the effect of the ions on the properties and structure of the water. This same effect should be responsible for the similarity in the variations of the zeta potential in the three models studied. © 1969 Dr. Dietrich Steinkopff Verlag.