Particle size characterization of highly concentrated alumina slurries by ultrasonic attenuation spectroscopy

Acoustic attenuation spectroscopy can characterize the particle size distribution (PSD) of highly concentrated slurries. This technique can directly measure the PSD of dispersions in highly concentrated slurries without considering the possible change of the PSD by diluting prior to measurement. The present study investigated a correlation between macroscopic and microscopic properties of alumina slurry when the added amount of dispersant was changed. It is found that the zeta potential of the Al2O3 Particles is not a factor of controlling the viscosity of alumina slurry, but particle size distribution width, represented as log (d(84)/d(50)), and large particle fraction (LPF) affect the viscosity of alumina slurry when all the amount of dispersant was adsorbed on to the alumina surface. When non-adsorbing dispersant was present in the slurry, the PSD and log (d(84)/d(50)) cannot be related with the behavior of viscosity. The obtained results demonstrated that the acoustic attenuation spectroscopy can open the way for correlating between macroscopic property such as viscosity and microscopic properties of slurry.