Electrokinetic Remediation for Environmental Security and Sustainability

15Management of Clay Properties Based on Electrokinetic Nanotechnology

D.S. Nesterov and V.A. Korolev

Department of Engineering and Ecological Geology, Faculty of Geology, M.V. Lomonosov Moscow State University, Moscow 119991, Russia

15.1 Introduction

The ultrafine‐dispersed fraction of clay soils (<0.1 μm) represented predominantly by clay minerals can be considered natural nanoparticles [1,2]. Accordingly, the term nanotechnology applies to the methods that affect the parameters of clay nanoparticles to control the macroscopic properties of clay soils.

Texture, physico‐chemical properties, and physico‐mechanical properties of clay soils depend on the parameters of the electrical double layer (EDL) formed around their particles. In turn, the EDL parameters (including electrokinetic potential ζ) of soil are controlled by the sign and value of the net particle electrical charge σ_P. Thus, studies of electrical charge components in clay soils and the regularities of their formation attract considerable attention from various researchers [3–14].

The electrical charge of clay nanoparticles forms for three reasons: (i) isomorphic substitutions within the crystalline lattice of clay minerals, (ii) protonation/deprotonation of nanoparticle surfaces, and (iii) adsorption of ions (different from H⁺ and OH⁻) from the pore solution [4–7,12–18]. Accordingly, total particle surface‐charge density (σ_P) is the sum of structural (σ₀), proton (σ_H), and ion‐sorbed (σ_S) surface‐charge densities, ...