Electrokinetic behavior of clay surfaces

Abstract

This chapter presents an overview of the electrokinetic properties of clay minerals to elucidate the electrokinetic behavior of clay surfaces and the mechanism of particle-particle interactions in aqueous systems. Suspended particulate matter, an important component of natural waters and ore dewatering systems, is composed of various clay particles that often control the kinetics and deposition of different organic and inorganic species. Interfacial phenomena at clay/water interface are usually controlled by electro kinetics properties including zeta potential (zp), the structure of electrical double layer (EDL), surface potential, and isoelectric point (iep). Zeta (ζ) potential is an intrinsic property of a mineral particle in a liquid. It determines the strength of the EDL repulsive forces between particles and identifies the stability of a colloidal system. The zeta potential (ζ) is known as the measurable surface potential of a particle viz., the potential at the shear plane. Zeta potential values for a montmorillonite samples at 0.8 and 2.7% solids concentration yielded slightly less negative trend particularly at low salinities.