Non-classical polarization of cations increases the stability of clay aggregates: specific ion effects on the stability of aggregates

摘要: Summary The stability of soil aggregates is closely connected with particle interaction determined by the combination van der Waals attractive force and electric repulsive according to Derjaguin–Landau–Verwey–Overbeek (DVLO) theory. Recently, hydration dispersion were put forward explain different behaviours cations or anions same valence at ion–surface interface, namely specific ion effect, where application classical DLVO theory had failed. Here, we employed two cation species, potassium sodium (K+ Na+), discover how effect would influence clay aggregate stability. The K+– Na+–montmorillonite was under electrolyte concentrations, indicated mass percentages particles diameters < 10, 5 2 µm released after breakdown. There large differences in K+- Na+- aggregates, strong effects shown. These could not be explained ionic size, forces between K+ Na+. We have proved that difference polarization Na+ charged surface responsible for effects. observed adsorbed hundreds thousands times larger than values; these results also verified independently methods. non-classical decreased field electrostatic repulsion adjacent thus strongly increased