Characterization of alumina suspensions by electroacoustics

Using the acoustophoresis technique three different dispersants were selected to investigate the effect of the volume fraction of the suspension on the minimum amount of dispersant required to give the maximum zeta potential. No effect was detected over a volume fraction range 0.11 to 0.35. The Acoustosizer was used to screen many dispersants for alumina in a relatively short time. From the viewpoint that the most stable suspensions are those with the greatest zeta potentials, then the following dispersants can be recommended: Reotan LA (0.25 mg/m2) Dolapix CA (0.20 mg/m2) and Dolapix PC33 (0.30 mg/m2). Vanisperse and Borresperse are poor. Polyacrylic acid and polymethacrylic acid were better than some commercially available products.