Attapulgite minerals are found in almost all parts of the world, but the proportion of deposits of industrial importance is limited to the United States, China, Spain, France, Turkey, Senegal, South Africa, Australia, Brazil, Israel, Saudi Arabia, Switzerland, the United Kingdom, Russia (Irkutsk, Irkutsk), Kyrgyzstan, Kazakhstan, Ukraine, Armenia, Azerbaijan, Belarus, Nepal and other countries, according to incomplete statistics, the world's proven reserves of about 150 million tons.
Attapulgite clay refers to a clay mineral with attapulgite as the main component. The attapulgite is a crystalline hydrated magnesium-aluminum silicate mineral with unique layer-chain structure characteristics. There is lattice replacement in the structure, and the crystal contains amorphous Na+, Ca2+, Fe3+, and Al3+ crystals. It is needle-like, fibrous or aggregated. The attapulgite has unique colloidal properties such as dispersion, high temperature resistance, salt and alkali resistance, and high adsorption and decoloration capability. And has a certain degree of plasticity and adhesion, its ideal chemical formula: Mg5Si8O20 (OH) 2 (OH2) 4 · 4H2O. There is an intermediate structure between the chain structure and the layered structure. The attapulgite is in earthy and dense mass and is produced in sedimentary rocks and weathered crusts. The color is white, grayish white, greenish gray, grayish green or weakly silky. The soil is exquisite, it has a slippery feel, light weight, brittleness, and the fracture is shell-like or jagged and has strong water absorption. Viscosity and plasticity when wet, shrinkage after drying is small, no significant cracks, water soak disintegration. The suspension does not flocculate and precipitate in the dielectric.
The attapulgite morphology is hair-like or fibrous, and is usually a carpet or soil aggregate. Mohs hardness 2-3, heated to 700 ~ 800 °C, hardness> 5. The specific gravity is 2.05 to 2.32.
Because of its unique crystal structure, attapulgite has many special physicochemical and process properties. The main physicochemical properties and process properties are: cation exchangeability, water absorption, adsorption and decolorization, large specific surface area (9.6-36 m2/g), and gum price and swelling capacity. These physicochemical properties are similar to those of montmorillonite.