Comparison of adsorption affinity of ionic polyacrylamide for the surfaces of selected metal oxides

The influence of metal oxide type on the adsorption affinity of anionic polyacrylamide for the solid surface was studied. There were selected three metal oxides: chromium(III) oxide, zirconium(IV) oxide and aluminium(III) oxide. The adsorption behaviour of high-molecular weight polymer containing 30% of carboxyl groups was determined based on the results of spectrophotometric, electrokinetic and turbidimetric measurements. The anionic polymer exhibits the greatest adsorption on the surface of chromium(III) oxide whereas PAM affinity for the aluminium(III) oxide is the lowest. The polymer presence has a pronounced impact on the electrokinetic properties of examined suspensions manifesting in changes in pHpzc and pHiep values of PAM-containing systems compared to those without polyacrylamide. The anionic PAM addition at pH 6 has the greatest effect on the stability of metal oxide aqueous suspensions.