Stability evaluation of aqueous alumina–zircon–silicon carbide suspensions by application of DLVO theory

The colloidal stability of alumina–zircon–silicon carbide suspensions has been investigated by measuring particle size distribution, sedimentation height and zeta potential. A polyelectrolyte (Dolapix CE-64) was used as a dispersant in different concentrations. Silicon carbide (SiC) particles lowered the zeta potential of suspensions, sedimentation height and also average particle size of resultant powders. It was concluded that the stability of alumina–zircon suspensions reaches an optimum condition by adding 20 vol.% SiC particles when using 0.5 wt.% dispersant, however, further increasing of SiC particles reduces the stability of suspensions. In this overview we present the basic theory for the double layer near the surface of alumina particles. Good agreement was found between dispersion characteristics of suspensions from theory and experimental results.