Influence of Added Electrolyte KCl Concentration on Dispersion of Almina Aqueous Slurry

Abstract

The influence of the added electrolyte KCl concentration was investigated on the dispersion of alumina particles in the alumina aqueous slurries. In the present work, the viscosities and the colloidal vibration potentials (CVP) were measured as a function of electrolyte KCl concentration in the range of 0 to 2000mmol·dm^-3 at the fixed concentrations of alumina (10 mass%) and dispersant (0.5 mass%) in the aqueous slurries. The viscosities of all slurries decreased with increasing the shear rate, so called the shear-thinning behavior was shown, and this behavior became vivid in more than 200mmol·dm^-3. The yield stresses obtained from the measured viscosities increased rapidly in more than 200mmol·dm^-3, too. The CVPs approached to 0μV in more than 200mmol·dm^-3 of electrolyte KCl concentration. The particle size distribution shifted to the larger radius side more than 200mmol·dm^-3. From the results mentioned above, it is considered that the agglomeration occurred in more than 200mmol·dm^-3 with electrolyte KCl concentrations in the present alumina aqueous slurry.