Bauxite is the raw material for the production of aluminum trihydrate and ultimately alumina or aluminum oxide. Depending on the quality of the ore, anywhere between two to four tons of bauxite is required for each ton of alumina produced.
Alumina is most widely known as the feed for the production of aluminum metal. However, this material can be further refined into a wide range of specialty aluminas for non-metallic applications.
The conversion of alumina to specialty alumina passes through various transitions depending on the product application:
The unique physical and chemical properties of this specialty or synthetic aluminum oxide plays an important role as an essential raw material for a range of market applications. The main criteria in terms of the selection of specialty aluminas include chemical purity - predominantly the level of soda - and the primary crystal size.
Aluminum oxide is extremely heat resistant with its fusion point being 2050°C (3725°F) and it is an excellent thermal and electrical insulator. In its crystalline form, which is called corundum, ist extreme hardness means it is suitable for use as an abrasive and as a component in cutting tools. To put things into context, corundum is in fact the second hardest material after the diamond. Furthermore, aluminum oxide adds exceptional mechanical strength, offers excellent resistance to corrosion and wear, and is a nontoxic material.