Impact of poly(vinyl alcohol) adsorption on the surface characteristics of mixed oxide MnxOy-SiO2

The poly(vinyl alcohol) (PVA) influence on the adsorption and electrokinetic properties of the mixed oxide MnxOy-SiO2/polymer solution system was examined. Three oxides differing with the MnxOy contents were applied (0.2; 1 and 3 mmol/g SiO2, respectively). The PVA with the molecular weight 100 kDa was characterized with the acetate groups content equal to 14 %. Adsorption, solid surface charge and zeta potential measurements were made as a function of solution pH (3-10). The obtained results showed that the PVA adsorption amount strongly depends on not only the solution pH, but also manganese oxide content on the mixed oxide surface. The higher solution pH value (or MnxOy content) is, the higher polymer adsorption is obtained. The PVA addition to the solid suspension causes minimal changes of the mixed oxide surface charge density, whereas the zeta potential of solid particles increases significantly in the polymer presence.