Coarse aluminas

The curves in Fig. 22 were calculated by means of the above equation, the points being experimental values. Figure 24 (Kwauk, Wang, Li, Chen and Shen, 1985) shows empirical correlations for the constants e and ea for FCC catalyst, fine and coarse alumina, pyrite cinder and iron ore concentrate. 

Experimental values for e and ea for five kinds of solid materials— FCC catalyst, fine alumina, coarse alumina, pyrite cinder, and iron ore concentrate—ranging in character from Geldart s Group A to weakly Group B, are shown in Fig. 58 (Li et al., 1982, 1981). The correlation could be fitted with the following empirical equations (Kwauk et al., 1985) ... 

Desportes et al. (2005) conducted experiments with coarse alumina particles (mean diameter 2.4 mm) to show that the homogeneity of solute distribution in the particles depends on the ratio between the two characteristic times tdry/twet- Two different experimental conditions that correspond to fast drying and to slow drying (low and high values of tdry/twet. respectively) were realized, as displayed in Tab. 7.4. Manganese nitrate was the precursor material. Material samples were removed after... 

Refractories. Calcined alumina is used in the bond matrix to improve the refractoriness, high temperature strength/creep resistance, and abrasion/corrosion resistance of refractories (1,2,4,7). The normal, coarse (2 to 5 )J.m median) crystalline, nominally 100% a-Al202, calcined aluminas ground to 95% —325 mesh mesh are used to extend the particle size distribution of refractory mixes, for alumina enrichment, and for reaction with... 

Butyl slurry at 25—35 wt % mbber continuously overflows from the reactor through a transferline to an agitated flash dmm operating at 140—160 kPa (1.4—1.6 atm) and 55—70°C. Steam and hot water are mixed with the slurry in a nozzle as it enters the dmm to vaporize methyl chloride and unreacted monomers that pass overhead to a recovery system. The vapor stream is compressed, dried over alumina, and fractionated to yield a recycle stream of methyl chloride and isobutylene. Pure methyl chloride is recovered for the coinitiator (AlCl ) preparation. In the flash dmm, the polymer agglomerates as a coarse cmmb in water. Metal stearate, eg, aluminum, calcium, or zinc stearate, is added to control the cmmb size. Other additives, such as antioxidants, can also be introduced at this point. The polymer cmmb at 8—12 wt % in water flows from the flash dmm to a stripping vessel operated under high vacuum to... 

Filter crucibles with a porous filter base are available in porcelain (porosity 4), in silica (porosities 1,2,3,4), and in alumina (coarse, medium and fine porosities) these have the advantage as compared with sintered crucibles, of being capable of being heated to much higher temperatures. Nevertheless, the heating must be gradual otherwise the crucible may crack at the join between porous base and glazed side. 

Figure 49 shows a set of bed collapsing curves for a Geldart Group A-A (for Geldart s classification of solid particles, see Geldart, 1972, 1973) binary solids mixture, two closely sized alumina powders, of average particle diameter 104 and 66 microns, respectively. The curve on the extreme left with 0% fines represents the pure coarse component, which is... 

Alumina gel(s), 2 422, 427-428 drying of, 23 66-67, 78 Alumina hydrates, 2 421, 428 crystalline, 2 422-426 economic aspects, 2 432 gelatinous, 2 426-427 health and safety factors, 2 432 manufacture, 2 428-431 properties of normal coarse grade, 2 429t shipping and analysis, 2 431-432 uses of, 2 432 Alumina hydroxides economic aspects, 2 432 health and safety factors, 2 432 physical data, 2 423t uses of, 2 432... 

Nori (laver), common and scientific names, 3 188t Norit, 4 741 Norlaudanosoline, 2 87 Normal coarse grade Bayer alumina hydrate, 2 428... 

Centrifugal Shot Casting Atomization (CSC) 150-1000 Standard deviation 1.3-1.4 Fe, Co, Ni, Ti alloys, Alumina, Uranium monocarbide 102-105 Narrow size distribution Coarse particles, Low EE... 

Indium also has many of the characteristics that make Al and Ga very useful for such applications. Particularly important is its capacity to dissolve Si, Ge and several lanthanide and transition metals, producing highly reactive forms of the elements. Moreover In does not form binaries with Si and Ge and has a low-melting point. RNiGe2 compounds, for instance, were prepared from stoichiometric quantities of the components in fine powder mixed with a 10 fold quantity of In in alumina tubes. These, flame sealed in fused silica tubes, were slowly heated to 1000°C, held at this temperature for a few hours, ramped down to 850°C, held for an additional 4 days and finally cooled down to room temperature over the course of another 4 days. Compound isolation from the In excess was performed by centrifugation at 300°C through a coarse frit. Further purification was carried out by a 15-minute submersion and sonication in 6 M aqueous HC1 (Salvador et al. 2004). 

Fig. 6.11 Comparison of expansion for admixture containing coarse and fine grinds of hydrated high alumina cement (courtesy NRC).

Silicate of soda, lime, alumina, and oxide of iron. Example —Coarse grew wine-bottle glass. 

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