Electrophoresis and zeta potential of kaolinite
Abstract
The effects of such parameters as preparation technique, pH, and sodium chloride concentration on the electrophoretic mobility of sodium kaolinite are examined using the single-particle microelectrophoresis technique. Cylindrical microelectrophoresis cells are shown to give misleading results and flat cells are used throughout. Theories regarding the surface electrical properties of kaolinite are discussed, and a method is proposed for calculating face zeta potential from experimental mobility. The method is based on an estimate of the edge zero point of charge. The Gouy—Stern—Grahame model was found to fit experimental data only after unrealistic adjustment of some model parameters.
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