Bentonite clay (Bentonite) in transliteration, causes and use is also called spot to take off the rock, Bentonite, etc., is based on montmorillonite (also known as microcrystalline kaolinite, montmorillonite) as the main component of clay rock - montmorillonite clay rock, often contain small amounts of illite and montmorillonite, zeolite, feldspar, calcite, etc. Montmorillonite is a small amount of alkali and alkaline earth metal hydrous aluminum silicate minerals.

Because of montmorillonite interlayer water and interlayer exchangeable cations, in accordance with the montmorillonite content of exchangeable cation type, content and crystal chemistry, etc., can be divided into sodium base bentonite bentonite (alkaline soil), calcium base bentonite (alkali) native soil and natural bleaching earth lived (acidic soil or clay) three kinds.

Physical properties:

Color general for white, weak yellow, because of iron content change in light grey, light green, pink, brown color, red, black etc. With waxy luster, earthy or grease.

Chemical composition:

Bentonite silica (SiO2) is the main chemical composition, 3 oxidation 2 aluminium (Al2O3) and water. Iron oxide and magnesium oxide content sometimes higher. In addition, calcium, sodium, potassium, etc often exist in different content in bentonite. Bentonite Na2O and CaO content on the physical and chemical properties of bentonite and technology performance impact is quite big.

The physical and chemical properties:

Bentonite has hygroscopicity, can adsorption 8 ~ 15 times the volume of water. After water absorption expansion, can expand to several times, can reach more than 30 times. That can disperse in water medium in colloidal suspension, the suspension has certain viscosity, thixotropy and lubricity. It with water, mud or sand and fine detrital material blending has plasticity and sintering. Has the strong cation exchange capacity. For a variety of gases, liquids, has certain adsorption ability of organic matter, up to 5 times the maximum adsorption of its weight, has the surface activity of the acid bleaching earth can adsorption non-ferrous material.

Physico-chemical properties of the bentonite contained mainly depends on its content and the types of the montmorillonite. General sodium base bentonite than calcium or magnesium based bentonite technologies of chemical and physical properties and superior performance. Mainly displays in: the water absorption speed is slow, but multiple large water absorption rate and inflation; High cation exchange capacity; Good dispersibility in water medium and high colloid valence; Its thixotropy and viscosity, good lubricity, colloidal suspension of high pH value; Good thermal stability; Have higher plasticity and strong caking property; Hot wet tensile strength and high dry strength. So the use of sodium base bentonite value and economic value is higher.

The application of sodium base bentonite:

(1) in the mechanical casting industry, as a foundry sand, binder, which can overcome the "sand" of casting "peeling phenomenon, reduce the casting scrap rate, ensure the accuracy of castings and finish.

(2) in the papermaking industry, is used as paper filler, enhance the brightness of paper.

3. Use of this product strong bonding performance, production for white latex, floor glue, paste, etc.

(4) because of its stable levitation, thickening, can effectively support distributed powder, as a water-based paint thickening additives precipitation.

5. At the same time take advantage of its excellent dispersibility and expansibility, high mud making rate, low fluid loss and colloidal properties and shear dilution ability, can be used as a drilling mud used sodium soil.