What are the uses of aluminum oxide?
1. Ruby and sapphire are primarily composed of aluminum oxide, with their varying colors due to different impurities. Sapphire, in particular, contains iron and titanium oxides, which give it its blue hue.
2. In the main component of bauxite, which is iron ore, the content of alumina is relatively high. Industrially, bauxite is purified into alumina through the Bayer process, and then transformed into aluminum metal through the Hall-Heroult process.
Aluminum reacts with oxygen in the air, forming a dense aluminum oxide film that covers the exposed surface of aluminum.
Aluminum is an excellent conductor of electricity and heat. The crystalline form of alumina, due to its high hardness, is suitable for use as abrasive materials and cutting tools.
Alumina powder is commonly used as a medium for chromatographic analysis.
