The influence of counterion size on short range repulsive forces at high salt concentrations was investigated with Al2O3 slurries at pH 12 coagulated with the chlorides of Li+, Na+, K+, Cs+, and TMA+ (tetramethylammonium)(1+). Measurements of viscosity, shear modulus, and yield stress of slurries, as well as the relative density and flow stress, of saturated, consolidated bodies were performed. The results clearly show that the range of the repulsive forces correlated with the size of the unhydrated ion; namely, stronger particle networks are achieved with smaller bare counterions. Our findings are contradictory to the widely accepted hydration force model, which attributes short range repulsive forces to the desorption of fully hydrated cations as surfaces are pushed together. However, the results are consistent with recently developed statistical mechanics models describing the interaction of ions of different sizes with surfaces and their hydration layers.

The influence of counterion size on short-range repulsive forces at high salt concentrations was investigated with silica slurries at various pHs. Ions from the lyotropic series of monovalent electrolytes (LiCl, NaCl, KCl, and CsCl) were used to coagulate dispersed slurries. Measurements of viscosity and sedimentation rate were performed. The results at high salt concentrations and volume fractions of silica clearly show that the extent of the short-range repulsive forces correlates with the size of the unhydrated ion. This trend is opposite to the ion-adsorption sequence on silica at low volume fractions of solids or lower ionic strength. Our results are also contrary to the widely accepted hydration force model but concur with the recently developed reference-hypernetted chain statistical mechanics models describing the interaction of ions with solvated surfaces.

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The mechanisms of the electromagnetic water treatment have been studied with a multitude of techniques and it has been found that the gas/water interface is essential to perturb water and suspended colloids. Perturbation of the gas/liquid interface results in nonequilibrium conditions which require hours to relax. Certain magnetic and electric fields also produce small amounts of ozone, superoxide, hydrogen peroxide, or atomic hydrogen. The addition of hydrogen peroxide or hydrogen did not produce equivalent effects without additional gas/liquid interface perturbations with electromagnetic fields (EMFs). Hydrophobic gases such as argon or carbon dioxide which promote clathrate-like structuring of water appear to be affected more significantly through the action of EMFs.

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