Attapulgite (Palygorskite)
摘要
Attapulgite, also known as palygorskite, has the chemical formula of Mg 5(H 2O) 4[Si 4O 10] 2(OH) 2·4H 2O or 5MgO·8SiO 2·9H 2O and is a 2:1-type (TOT-type) trioctahedral layer-chain structure of magnesium-rich silicate. The International Mineralogical Association classifies the sedimentary origins in clay deposits and soils as attapulgite, while the hydrothermal origins are referred to as palygorskite. In the chemical classification of mineral crystal chemistry, attapulgite belongs to the silicates, the layer-structured silicate subclass, and the palygorskite group. In the structural-functional classification of mineral materials in mineral material science, attapulgite (palygorskite) belongs to the one-dimensional structural mineral category and the functional mineral subcategory.