premium aluminas for advanced applications


Calcined Aluminas for the Refractory Market

Almatis offers high-quality calcined aluminas, primarily consisting of robust sintered agglomerates of individual alumina crystals. These aluminas, supplied primarily in ground (<63μm) or fine-ground (<45μm) forms, are distinguished by their partially retained agglomerates, unlike the fully ground reactive aluminas.

Our calcined aluminas are classified by soda content, particle size, and calcination level to meet diverse application needs. They excel as matrix fillers, enhancing natural raw material-based formulations by increasing alumina content and improving particle packing. This results in elevated refractoriness and stronger mechanical properties, such as abrasion resistance and rupture strength.

The efficiency of calcined aluminas is also determined by their surface area and residual agglomerate balance. While low surface area aluminas are preferred for bricks and castables, our special high surface area variants are ideal for gunning and ramming mixes, effectively replacing clay as plasticizers. These adaptations ensure minimal shrinkage post-drying and firing, maintaining optimal installation characteristics.


Featured Products




For refractory matrix enhancement
Particle size / D50 = 3.5µm
Na2O Content = 0.15%


Product Data Sheet



CT 800 FG

Alpha-alumina for refractory matrix enhancement
Particle size / D50 = 3.5µm
Na2O Content = 0.12%

Product Data Sheet



CT 10 SG

Special alumina for gunning applications
Particle size / D50 = 3.0µm
Na2O Content = 0.4%


Product Data Sheet



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