Ferrous silicate

The chemical properties of copper, lead, lead-zinc, and zinc slags are essentially as ferrous silicates, whereas nickel slags are primarily calcium/magnesium silicates. Table 4.13 lists typical chemical compositions of these slags. 

Terre verte or Veronese earth is a magnesium clay coloured by ferrous silicate. It is very rich in silica and poor in alumina and usually contains, besides magnesia, also small quantities of alkali, and sometimes lime and carbonic acid. 

The slag of ferrous silicate floats on top of the molten copper and is poured off, while the molten copper is poured into molds and allowed to cool. This product is known as blister copper and ordinarily contains about 2% impurities, among which are several noble metals. Since greater purity is usually required, the blister copper is refined by elec-... 

If this newly created ocean were left undisturbed for a few hundred million years, its waters would evaporate and be transported onto the continents in the form of precipitation streams would transport their loads into it. The sediment created in this ocean would be uplifted and incorporated into the continents. Gradually, the influence of the continental debris would be felt and the pH might shift a little. Iron would be oxidized out of the ferrous silicates to make iron oxides, but the water composition would not vary a great deal. 

Reflectance spectra of ferrous silicates in Moon rocks... 

Iron, also present in all concentrates, reacts with silica to form ferrous silicate ... 

The silicates formed in reactions 2 and 3 fuse with the added fluxes to form a liquid slag at which point carbon monoxide loses its effectiveness as a reducing agent. Unreacted carbon from the fuel then becomes the predominant reductant in reducing both stannous silicate to tin and ferrous silicate to iron. The metallic iron, in turn, reduces tin from stannous silicate ... 

An ortho-silicate of iron, termed fayalite or iron olivine, Fe2Si04, was first found on Fayal Island in the Azores. It had crystallised m tabular rhombs of Fe2Si04, very similar to the ferrous silicate present in certain slags.3 The axial ratios 4 are... 

Thus a recent formation of pyrites has been observed at Karlsbad, in the well-known springs, which have a temperature of about 55° C. The waters are faintly alkaline and contain dissolved sulphates and a trace of hydrogen sulphide.3 Similarly the Tuscan lagoons are gradually depositing pyrites, whilst the hot vapours of the Icelandic fumaroles are slowly converting the ferrous silicate of the rocks into pyrites.4... 

PRIMARY HEMATITE ZONE (HEMATITE MAY BE REPLACED OlAGENETICALLY BY MAGNETITE, FERROUS SILICATES OR SIDERITE)... 

Nickel silicate and ferrous silicate are the preferred catalysts in the Smuda process. The Smuda catalyst is a layered silicate clay framework with ordered nickel (or iron) atoms inside. The catalyst is charged at 10 wt% ratio of the plastic feedstock. The catalysts are based on layered silicates with Lewis acid activity [24]. Catalytic cracking results in very little noncondensable gas (<1%) and minimal carbonaceous char. The hfe of the Smuda catalyst is approximately 1 month [24]. 

Hematite o -Fe203 <43.9 + 0.2 Results from the weathering and oxidation of Fe (esp. ferrous) silicate minerals or the aging of HFO. May form from HFO by direct solid-solid transformation. Common in warm climate soils, and the chief oxyhydroxide in red-bed sediments. 

KEL] Kelley, K. K., The specific heats at low temperature of ferrous silicate, manganous silicate and zirconium silicate, J. Am. Chem. Soc., 63, (1941), 2750-2752. Cited on pages 217, 218, 219. 

Amphibole Calcium, sodium, magnesium, ferrous silicate Na2C03, H2SO4 H2SO4 R-801,825 ... 

Various chrome-free refractory materials have been studied by dip testing of these refractories in ferrous silicate and calcium ferrite slags typical of those used in copper production furnaces. More recently, a rotating sample test procedure has been employed. 

Minerals which also contain iron will yield ferrous ions when fused with zinc chloride and they too give a red color with dimethylglyoxime and ammonia (compare page 267). Consequently, in such cases it is best to test for ferrous silicates as outlined on page 563 and if the response is positive the ammoniacal suspension should be warmed with hydrogen peroxide prior to the centrifuging. Ferric hydroxide is precipitated, while the nickel tetram-mine ions remain in solution. 

Jackson WE, Mustre de Leon J, Brown GE Jr, Waychunas GA, Conradson SD, Combes J-M (1993) High-temperature XAS study of ferrous silicate liquid reduced coordination of ferrous iron. Science 262 229-233... 

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