Brown fused alumina

Figure 1 Spatial distribution of components in a ceramic material (brown fused alumina) as shown by overlaid elemental distribution using energy dispersive analysis.

Electrofused alumina-zirconia (EFAZ) is obtained by a process similar to that used for preparing brown fused alumina by electrothermal fusion and reduction by metallurgical coke at 2100°C of a mixture of bauxite ore, zircon sand, and scrap iron in a tilting and triphased electric-arc furnace. After quenching the molten mass, the resulting product obtained is about... 

Alumina (non metallurgical grade) Australia (44,100), USA (5100), and Jamaica (3400) 50,000,000 calcined alumina (CA) 75-85 tabular alumina (TA) 435-580 white fused alumina (WFA) 600-900 brown fused alumina (BFA) 600-700... 

Some materials have characteristic microstructures that can be used for confirmation of their presence. For instance, fused magnesia, sintered magnesia, and seawater magnesia are structurally different. Similarly, calcined alumina, tabular alumina, and white fused and brown fused alumina all have very different characteristics. 

H2SO4, anhydrous dication), pK " with 3,4-hydrated species), pKl 12.1 (hydrated anion). Purify quinazoline by passage through an activated alumina column in C6H6 or pet ether (b 40-60"). Distil it undar reduced pressure, sublime it undo-vacuum and crystallise it from pet ether. The.picrate has m 188-189" (from MeOH). [Armarego J Appl Chem 11 70 1961, Armarego Quinazolines, Fused Pyrimidines Part I Brown Ed, Wiley-Interscience 1967, Brown Quinazolines Supplement 1 Taylor Ed, Wiley-Interscience 1996, ISBN 0-471-14565-3 for covalent hydration see Albert Armarego Adv Heterocycl Chem 4 1 1965, Beilstein 23 H 175, 23 II 177, 23 III/IV 1221.]... 

The multitude of refractory aggregates (for example, calcined clay, flint clay, andalusite, mulhte, bauxite, fused white or brown alumina, sintered alumina, etc.) and the different grain sizes of these materials—in addition to the big variety of bonding agents, additives, and mixing liquids—enable endless combination possibihties in development work on unshaped refractory products. Therefore, a qualitative standardization is not really possible as it is the case for refractory bricks. As a result of the ENV 1402-1 standard, which now provides a more precise definition of the products, there will probably be adjustments on the market in the long run. If also considering economic aspects, suitable products will obviously be developed on the basis of all the available constituents. 

Table 12 lists properties of eight different industrial refractory castables and gives a comparison between RC- and MCC-type castables. Chamotte (A 1 -I- A 2), flint clay (B 1 - - B 2), flint clay/fused brown alumina (Cl -I- C 2), and tabular alumina (D 1 - - D 2) were selected to serve as examples of the raw material... 

The first-mentioned product G is a ULCC-type castable and based on fused brown alumina/SiC with approximately 3% carbon. It is applied in the casthouse of blast furnaces, especially in the pig iron trough. The second example H is a spinel-forming ULCC castable, which is used as wear lining in steel ladles. 

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