Estimation of the Electrostatic Repulsive Force among Charged Clay Particles in Aqueous Systems

Electrostatic force of charged particles is crucial for some important physical processes in a wide range of scientific fields, such as the bio-molecular assemblies in modern biophysics, diffusion-controlled chemical kinetics and ion transport in soils, as well as soil particle aggregation and dispersion, which may be closely relevant to soil erosion and water eutrophication in environment. In this report, an approach for theoretical estimation of the electrostatic repulsive force among clay particles in aqueous solutions was suggested. The results showed that:

1

) the suggested theory for the electrostatic force calculation was well verified by our experiment;

2

) the accurate surface potential value is the key in obtaining an accurate calculation of the electrostatic force;

3

) the electrostatic repulsive force among clay particles in aqueous solution will sharply increase with the decrease of electrolyte concentration in bulk solution of soil. The suggested approach may be important in the studies of soil particle interaction and charged particle transportation.