Drainpipes laid in clayey soil can be completely crushed by the swelling of the clay in soil. The swelling capacity of montmorillonites group minerals is very high. A piece of gel of this mineral will swell upto 16 times of its original volume when placed in water.
Depending on their plasticity clays may take upto 20% […]

The surface area of clays was only indirectly measured by two of its functions;
1. Heat of wetting
2. Water Adsorption
All dry colloids on being wetted with water develop heat proportional in amount to the surface area involved. Since the interior of the solid particles cannot react with water and the only part that reacts is […]

The extensive internal surface in a wad of clay, combined with the surface activity of individual particles determines its high adsorbity power, which is particularly evident in its behaviour with respect of water. Dry clay takes up water from the atmosphere in proportion to the extent of its internal surface which inturn depends on particle […]

Particle size is not the only factor determining the adsorption of dyestuffs. Since the specific adsorption capacity of different clays are not same, the adsorption of alkali ions has been shown to be linear function of the surface. The high adsorption capacity of clay for dyestuffs is well known. It has been used for determining […]

As per Harman and Fraulini, the ionic exchange capacity, permeability, heat of wetting and drying shrinkage are not directly related to grain size. However permeability depend on both the apparent and the true surface, particularly on the pore space, which in turn depends on the packing density.
If the individual clay minerals are converted to the […]

In fine ceramics it is well known that clays from slips fluidized with alkali cannot be formed on the wheel after filter pressing. The explanantion lies in the much higher water content and thixotropy of Na clays. The shearing strength actually diminishes sharply with rising Na content. Plasticity and drying shrinkage of Ca clays were […]

The base exchange capacity is increased by dry grinding and diminished by wet grinding. Among the metallic ions those of Ca and Mg account for by far the major part of the extractable ions and one gains the impression that the adsorbed alkalies are present only as chance impurities.
Na clays have the highest zeta potential. […]

In hydraulic engineering use is made of the ability of alkali ions to bind water for sealing dykes and soil layers by saturating clay with NaCl solution. The sodium clay thus produced binds the seeping water by swelling and the soil is rendered watertight. The different extent to which water is bound by H+, Ca++ […]

The adsorption of cations on clay must be regarded as taking place in such a way that a series of oriented dipoles lies between cations and the colloidal particle. They form the double layer. The adsorption cations and dye stuffs and also part of the water takes place mainly along the edges of crystals.
The maximum […]

If clay is electrolised between two diaphrams, it yields more cations than anions which is also taken as proof of the anionic nature of the clay. The pH of the clay cannot be measured in a filtrate from the clay suspension nor can it be determined by calorimetric methods. It must be observed in the […]