Investigations of flocculation possibilities of the water alumina suspension in the presence of nonionic polymer

The effect of solution pH and molecular weight of polyethylene glycol (PEG) and polyethylene oxide (PEO) on their adsorption as well as stability of the colloidal Al2O3 water suspension was studied. The following methods were applied: turbidimetry, spectrophotometry, viscosimetry, potentiometric titration and microelectrophoresis.It was shown that the increasing solution pH affects conformation of the adsorbed macromolecules which affects the stability properties of such systems. The polymer adsorption causes deterioration of the stability conditions of the investigated alumina systems in comparison to those without polymer at all investigated pH values. At pH 3 and 6 the effect of the suspension destabilization is significantly smaller than at pH 9. The most effective flocculent of Al2O3 water suspension is PEO of the molecular weight 218,000 at pH 9.