Introduction to Activated Alumina Substances

Alumina, commonly known as bauxite, has a chemical formula of Al2O3. White powder, density 3.9～4.0g/cm³, melting point 2050℃, boiling point 2980℃. It is insoluble in water, but slowly soluble in concentrated sulfuric acid. It can be used to smelt metal aluminum, and it is also a raw material for making crucibles, porcelain, refractory materials and artificial gemstones. Alumina used as adsorbent, catalyst and catalyst carrier is called "activated alumina", which has the characteristics of porosity, high dispersion and large specific surface area, and is widely used in petrochemical, fine chemical, biological and pharmaceutical and other fields.
Activated alumina is generally prepared by heating and dehydrating aluminum hydroxide. Aluminum hydroxide is also called hydrated alumina, and its chemical composition is Al2O3 nH2O. Usually, it can be divided into trihydrate alumina and monohydrate alumina according to the number of crystal water contained. After aluminum hydroxide is heated and dehydrated, γ-Al2O3 can be obtained. That is commonly referred to as activated alumina.