Ferrous aluminate

Figure 7 Experimental XRD spectra for odinite and calculated diagrams for hypothetical minerals using the NEWMOD program (Reynolds, 1985) are shown. The berthierine spectrum was simulated using a ferrous-aluminous 7 A clay structure with 3-6 coherent diffracting domain structure. The mixed layer 7 A/smectite mineral berthierine/nontronite was modeled using 60% berthierine layers and 3-6 layer coherent diffracting domains in a disordered (R = 0) structure (after Odin, 1988, p. 162).

Matsui has found for an I.G. catalyst that the aluminum oxide at its surface is present in the form of ferrous aluminate which covers parts of the metal surface, consisting of a-iron. The same author prepared a small single crystal of iron coated by an oxide film and studied its structure by the transmission method of electron diffraction. The pattern shows, Fig. 14, that the (111) plane of magnetite is produced parallel to the (111) plane and also to the (110) plane of iron, suggesting that with the... 

I.G. catalyst a similar orientation may exist between the crystals of a-iron and the spinel ferrous aluminate. 

Barium metal and most barium compounds are highly poisonous. A notable exception is barium sulfate which is nontoxic because of its extreme iasolubihty ia water. Barium ion acts as a muscle stimulant and can cause death through ventricular fibrillation of the heart. Therefore, care must be taken to avoid contact with open areas of the skin. Workers must wear respirators (of type approved for toxic airborne particles), goggles, gloves, and protective clothing at all times. The toxic barium aluminate residue obtained from barium production is detoxified by reaction with a solution of ferrous sulfate and converted iato nontoxic barium sulfate. According to OSHA standards, the TWA value for Ba and Ba compounds ia air is 0.5 mg/m. ... 

Figure 17. Proposed phase relations where K is a mobile component and Al, Fe are immobile components at about 20°C and several atmosphere water pressure for aluminous and ferric-ferrous mica-smectite minerals. Symbols are as follows I illite G = non-expanding glauconite Ox = iron oxide Kaol = kaolinlte Mo montmorillonite smectite N nontronitic smectite MLAL aluminous illite-smectite interlayered minerals Mlpe = iron-rich glauconite mica-smectite interlayered mineral. Dashed lines 1, 2, and 3 indicate the path three different starting materials might take during the process of glauconitization. The process involves increase of potassium content and the attainment of an iron-rich octahedral layer in a mica structure.

The compositional variation from grain to grain is greater in low temperature 14 8 chlorites and this scatter decreases as metamorphic grade increases. Low temperature chlorites tend to be ferrous and aluminous. 

Experimental work (Velde, in press) helps to establish the relations between diocathedral and trioctahedral or aluminous and magnesio-ferrous... 

The major reactions are complicated by a number of minor or secondary reactions, and by impurities in the raw materials. As a result the black ash may contain 1 to 2 per cent, of sodium silicate to If per cent, of sodium aluminate 1 per cent, of sodium ferrous sulphide small proportions of sodium cyanide and thiocyanate derived from the nitrogen of the coal a relatively small amount of ultramarine etc. Proposals to use barium carbonate, etc., in place of limestone in the black-ash process are indicated in connection with the preparation of sodium carbonate from sodium sulphide. 

In general, the minerals now identified as chamosite are found in iron ore bodies of sedimentary origin (e.g., Maynard, 1986 Fernandez and Moro, 1998 Wiewora et al, 1998 Kim and Lee, 2000). Chamosite associated with iron oxides appears to follow a compositional trend from iron oxides plus kaolinite to chlorite, as indicated in Figure 8, using the data of Velde (1989). The recombination of iron oxide in the presence of kaolinite gives an aluminous, ferrous mineral, chamosite. This mineral is formed under burial conditions where ferric iron oxide is reduced to feiTous iron which is rapidly incorporated into a 7 A chlorite mineral. Both chamosite and berthierine result from the reduction of ferric iron to ferrous iron. 

Eremin, N.I. Tkacheva, L.V. Makarenko, V.N. "Investigation of the Kinetics of the Decomposition of Kaolinite in Alkaline and Aluminate Solutions," Soviet Non-ferrous Metals Research 1978, 6(5), 197-199. 

Calcium aluminate cements are examples of conventional refractory castables. Development of low, ultralow cement, no-cement pumpables, and self-flow castables has increased the applications of monolithics [42], Steel-reinforced refractories (SFRR) are used in applications that include ferrous and nonferrous metal production and processing, petroleum refining, cement rotary kilns, boilers, and incinerators. Steel fibers are added to refractory concretes to improve resistance to cracking and spalling in applications of heavy thermal cycling and thermal shock loads. 

Electrolytes which do not afford ionic complexes with common hexitols and reducing sugars are aqueous solutions of lead acetate, copper sulfate, zinc sulfate, ferrous ammonium sulfate, calcium chloride, potassium dichromate, ferric chloride (pH 3), aluminum sulfate, magnesium sulfate, sodium sulfate, potassium antimonyl tartrate, sodium arsenate or arsenic acid, sodium phosphate, and hydrochloric acid. It is not certain whether sodium aluminate (in 0.1 N sodium hydroxide) affords ionic complexes with carbohydrates, as aqueous alkali, alone, permits their migration during electrophoresis. 

Commonly used coagulants are inorganic (Bratby, 2006 Anon, 2014) and are based on aluminum (i.e., aluminum sulfate, aluminum chloride, sodium aluminates), iron (i.e., ferric sulfate, ferrous sulfate, ferric chloride, ferric chloride sulfate), hydrated lime, or magnesium carbonate. They are often the cheapest, most widely available, and effective coagulants. 

Dimethylaminoethyl acrylate methyl chloride quat. Dimethylaminoethyl methacrylate dimethyl sulfate quat. Dimethylaminoethyl methacrylate methyl chloride quat. Dimethyl diallyl ammonium chloride Ferric chloride Ferric chloride hexahydrate Ferrous sulfate heptahydrate Guar (Cyanopsis tetragonoloba) gum Hectorite Hydrogenated tallow 1,3-propylene diamine Kaolinite Potassium alum dodecahydrate Sodium aluminate coagulant, yarn processing Polyquaternium-6... 

Coagulants are often added in conjunction with lime to increase the settling rate of calcium carbonate and magnesium hydroxide. Most of these coagulants are acidic in nature and react with the alkalinity of the water. Commonly used coagulants include aluminium sulphate (alum), sodium aluminate, ferric sulphate and ferrous sulphate (Table 6.8). Alum reacts with natural alkalinity in water to form aluminium hydroxide floe (Equations 2.5—2.8) [14]. About 1 ppmofalumdecreaseswater alkahnity by 0.5 ppm and produces 0.44 ppm of CO2 ... 

Calcium aluminate cements may differ distinctly in their color, which is determined mainly by their iron content. The gray color of calcium aluminate cements is caused by the ferrous form of iron, whereas ferric compounds lead to a brown color. The cement gets darker with increasing iron content and—at a constant content of this element—with an increasing proportion of ferrous species. High-alumina cements made from iron-free starting materials are white. 

The results of Wielers and co-workers have shown that Fe(II) is stabilized by some interaction with alumina. The stabilization may be due to the formation of FeAl204 or, more probably, to an interaction between ferrous oxide and an alumina or iron(II) aluminate surface. Kock and co-workers demonstrated the stabilization of Fe(II) by alumina using magnetic measurements. The authors studied the reduction of goethite (FeOOH), hematite (Fe203), a physical mix of FeOOH and alumina, and FeOOH deposited on alumina with carbon monoxide. They raised the temperature of their samples held in a flow of 5% carbon monoxide in helium, with a heating rate of 4.8 K min up to a temperature of 770 K and... 

Pack cementation is widely used to confer oxidation resistance on ferrous alloys. Usually relatively expensive aluminum or binary alloys grade reagent is used during the pack process with aluminum as a source. Pack cementation processes include aluminizing, chromizing, and siliconizing. Components are packed in metal powders in sealed heat-resistant retorts and heated inside a furnace to precisely controlled temperature-time profiles. In the aluminizing process, a source... 

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