Effect of charge type and density of polyacrylamide on the electrokinetics behavior of flocculated bentonite suspensions

Abstract

The study of electrokinetics behavior of clay suspensions is of fundamental importance in many industrial applications. This paper addresses the electrokinetics behavior of polyacrylamide (PAM)- bentonite suspensions. The impact of surface charge distribution of PAM-bentonite suspensions on the degree of flocculation is examined. The influence of the flocculant properties such as the surface charge type and density, molecular weight and concentrations on the point of zero charge (PZC) of bentonite is investigated. In this study, the effect of different PAM types such as cationic, anionic and amphoteric PAM on the destabilization and flocculation of the systems is studied using zeta potential measurements. Flocculation for each polyacrylamide is conducted using jar tests and the optimum flocculant dosage is defined from turbidity and zeta measurements. This work has provided fundamental understanding of the influence of surface charge types and densities of PAM on the stabilization or destabilization of flocculated bentonite.