One, Differences in Physical and Chemical Properties
Alumina Hydrate: A white amorphous powder with a melting point of 300°C, it exhibits slow, persistent, and strong anti-acid properties, has astringent effects, and provides mucosal protective action, leading to constipation. It does not produce carbon dioxide, has no acid rebound, and does not cause alkalosis.
Alumina: A white solid with a melting point of 2303K, it is difficult to dissolve in water, odorless, tasteless, and extremely hard. It is hygroscopic but does not effloresce (non-hygroscopic after burning).
Purpose Varies
Alumina Hydroxide
(1) In the main composition of bauxite, the content of alumina is high. Industrially, bauxite is purified into alumina through the Bayer process, which is then converted into aluminum metal using the Hall-Héroult process.
(2) Aluminum reacts with oxygen in the air to form a dense aluminum oxide film, covering the exposed surface of aluminum to the atmosphere.
Aluminum is an excellent conductor of electricity and heat. Aluminum oxide crystals, due to their high hardness, are suitable for abrasive materials and cutting tools.
Alumina powder is commonly used as a medium for chromatographic analysis.
In August 2004, a scientist at the U.S. 3M Company developed an alloy composed of aluminum and rare earth elements, which was used to produce strengthened glass known as transparent alumina.
2. Aluminum Oxide:
Alumina hydrate is a widely used inorganic flame retardant. As a flame retardant, alumina hydrate not only serves to retard flames but also prevents smoke, drips, and toxic gases. Due to these properties, it has gained extensive application and its usage has been increasing year by year.
The application scope includes industries such as thermosetting plastics, thermoplastic plastics, rubber, coatings, and construction materials. Additionally, aluminum hydroxide is a basic raw material for aluminum fluoride, widely used in the electrolytic aluminum industry.
