Aluminium oxide (Al2O3 or Al) is an amphoteric oxide that is soluble in both acid and base. It is an important component in the manufacture of metallic aluminum as it forms a dense protective layer on aluminium surfaces when exposed to air.
Typical industrial applications of aluminium oxide are found in refractories, ceramics and abrasives where its strength and hardness makes it useful. It is also used as a fire retardant/smoke suppressant, a coating for titania pigments and in some compact fluorescent lamps.
In many chemical reactions, aluminium oxide can be used as a catalyst. It is a useful catalyst in hydrodesulfurization of sulfur-containing compounds, some Ziegler-Natta polymerizations and other hydrometallurgical processes. It is also a valuable catalyst for crack-I ing petroleum and pyrolytic decomposition of organic compounds such as alcohols and certain halogen compounds.
Insulation for furnaces
For high-temperature furnaces, aluminium oxide is used to manufacture blankets and insulated boards and loose fibre forms. It is available in various granulometric sizes and can be combined with varying percentages of silica.
Aluminosilicate glass is another common application of aluminium oxide. This type of glass is typically made from 5% to 10% alumina.
The addition of aluminium oxide 38 to a clay composition for extrusion forming increases the resistance to degreasing, and improves its mechanical properties under both wet and dry conditions. The effect of this material is especially visible when using a high-speed extrusion machine. The resulting ceramic tiles have a comparatively low porosity and are more resistant to damage and tribological effects than the clay tile without the addition of aluminum oxide 38.