Influences of media on dispersion behaviors and electrokinetic properties of nanoceria particles in concentrated slurries

Abstract

Both dispersion behaviors and electrokinetic properties of nanoceria particles in concentrated slurries were researched with the ultrasound attenuation and electroacoustic technologies, and influences of dispersing media were analyzed. It was found that particle size distribution (PSD) of the nanoceria could be fitted well by the bimodal model with lower errors, and zeta potential of the particles could be obtained by direct measurements due to small primary size less than 50 nm. And the media had great influences on both dispersion behaviors and electrokinetic properties of the nanoceria particles in slurries. The nanoparticles could be dispersed to primary particles as a whole in the slurry with de-ionized water when they had absolute zeta potential higher than 30 mV, which accorded well with the Derjaguin-Landau-Verwey-Overbeek (DLVO) theory. But non-DLVO interactions would appear and complicate the situation in the slurry with polyelectrolytes. The practical analysis ascertained some basic details in ultrasound and electroacoustic measurement of nanoparticles in concentrated slurries, as well as microscopic mechanisms for dispersion of nanoparticles, both of which would promote understanding and optimizing dispersion behaviors of nanoparticles in concentrated slurries.