POLYMERIC FLOCCULANTS.

Abstract

The vast majority of commercial anionic polymers are based on partially-hydrolyzed polyacrylamide. Other examples of synthetic polymeric flocculants are nonionic(polyvinyl alcohol, polyethylene oxide), anionic (sodium polystyrene sulphorate), and cationic (polyethyleneimine, polydiallyldimethylammonium chloride) polymers. The nature of polymeric flocculants is discussed from the bridging and charge neutralization mechanisms. One method of distinguishing between the polymer bridging and change neutralization mechanisms is to examine the effect of high shear on the aggregates. In the case of bridging, flocs do not readily reform, as mentioned above, whilst those produced by charge neutralization can be broken and re-formed very easily.