Pressure filtration of dispersed and flocculated alumina slurries

The pressure-filtration behaviors of dispersed and flocculated alumina slur ries at high percent solids were investigated with the objective of determi ning the effect of surfactant type and concentration on slurry properties. A high-purity alumina powder was used as a model solid. Dispersion of the a lumina was controlled by pH and by surfactants that are known to act as ele ctric and steric stabilizers. The effects of both ionic and nonionic surfac tants were investigated Surface charge measurements of the slurries were ca rried out by an electrokinetic sonic amplitude (ESA) method to better under stand the mechanisms. The effect of surfactant type and concentration on th e kinetics of pressure filtration and cake properties are discussed.