A is for Aluminum Oxide
Aluminum oxide marks the start of our new social media series, the COFERMIN Raw Materials Alphabet. Over the coming months, we will be presenting selected industrial raw materials and materials from A to Z that form the basis for numerous industries and industrial end products or round off the product. We will look at various evaluation criteria and use them to create a COFERMIN quartet.
But first of all, what exactly is aluminum oxide?
Aluminum oxide, chemically known as Al₂O₃, is a compound of aluminum and oxygen. It is a white, crystalline powder and occurs naturally mainly as the mineral corundum . Industrially, aluminum oxide is extracted from the ore bauxite using the Bayer process. In this process, bauxite is treated with caustic soda, which produces aluminum hydroxide. This is then converted into aluminum oxide by heating (calcination). Aluminum oxide is also an important intermediate product in the production of metallic aluminum, which is obtained from Al₂O₃ by fused-salt electrolysis.
Aluminum oxide is an extremely hard material with a Mohs hardness of 9, making it one of the hardest natural substances after diamond. It has a high melting point of around 2,072 °C, is electrically insulating, and is chemically very stable. One of its special properties is its amphoteric nature, which means that it can react with both acids and bases.
Aluminum oxide is a versatile material with great industrial significance.
Its hardness, temperature resistance, and chemical stability make it irreplaceable in many technical and scientific fields. At the same time, it forms the basis for aluminum production and is thus a central component of modern industry.
The possible applications of aluminum oxide are very diverse:
- In metallurgy, it serves as the starting material for aluminum production.
- In the ceramics industry, it is used for the manufacture of refractory materials and technical ceramics.
- Due to its hardness, it is used as an abrasive and polishing agent in numerous industrial processes.
- In electronics, it serves as an insulator and protective layer in microchips.
- In medical technology, aluminum oxide is used for biocompatible implants such as artificial joints.
- It is also used in optics—synthetic rubies and sapphires made of pure Al₂O₃ are used for lasers and jewelry.
Focus on origin and sustainability
The origin of aluminum oxide is also an important factor, as it influences the quality of the raw material, its availability, and its regulatory classification. That is why we select our raw materials in line with our ESG commitments. We are committed to reducing social inequalities along the supply chain and promoting sustainable production and logistics processes. (Link to landing page or blog).
Due to these factors and the certainty that we will continue to face challenges in the supply of raw materials, such as fluctuating world market prices, varying qualities, and high regulatory requirements. We create flexible and needs-based delivery capabilities for our customers through our global network and high-quality raw materials.
Aluminum oxide:
- Economy: Closely linked to the global aluminum industry. 90% of global Al₂O₃ production serves this purpose.
- Fire resistance: Ideal for high-temperature applications.
- Country of origin: China, Brazil, Australia
- Sustainability: Medium (recyclable, but energy-intensive to produce)
- REACH-compliant: Yes
The COFERMIN raw materials alphabet continues!
If you say A, you have to say B, so our next blog in this series will be about “B” for bentonite. A clay mineral that is in demand in numerous industries as a binding agent, sealant, and filtration aid. But we don’t want to give too much away. Stay tuned for the next post.
Do you work with aluminum oxide or are you planning a new process? Contact our team for a no-obligation consultation or visit our product overview at www.cofermin.de.
