Carbided iron

The steady state rates of hydrocarbon synthesis over the carbided iron surface are given in Table I. The reaction rates have been normalized to the physical surface area of the starting iron powder [18 M /g] and are reported in molecules/cm sec. A turnover... 

Thermal reduction processes are not being practiced anywhere in the world at present for large-scale production of sodium. Such methods, however, can he conveniently adapted for laboratory preparation of metalhc sodium. Sodium can be prepared by thermal reduction of its hydroxide, carbonate, or chloride at elevated temperatures. These salts are heated with carbon, calcium carbide, iron carbide, ferrosilicon, or other reducing agents at temperatures above 800°C under vacuum ... 

Microstructures in cast irons are also dramatically influenced by cooling rates. If cooling is rapid, no graphite precipitates. Rather, the alloy solidifies in the metastable Fe-Fe3C state. In that state, the carbon is combined with iron as iron carbides. The fractured surface of carbidic cast iron is white. Such irons are hard and are not readily machined. Carbidic iron castings are used for some special applications, when abrasion resistance is important. 

The general methods for the production of the alkali metals are (1) Electrolytic processes involving the electrolysis of (a) the fused hydroxide, or (b) a fused salt— chloride, nitrate, cyanide, etc. (2) Chemical processes involving the reduction of hydroxide, or carbonate, or other salt with carbon, metal carbide, iron, calcium, magnesium, aluminium, etc. W. Spring 5 claims to have reduced a little potassium chloride by passing hydrogen over the salt at a red heat. 

Thus, we project that hydrogenation of carbidic carbon to form CH species, polymerization of the CH species leading to C-C chain growth, and chain termination leading to the products (followed by their desorption) will occur on carbided iron surfaces where the reaction energetics resembles that on metallic Pd or Pt surfaces. Table XIII clearly shows that the activation barriers for all processes of recombination and desorption are much smaller on Pt than on Fe. Moreover, from Table XIII it follows that on a pure Fe surface such as Fe(110), the desorption energies for... 

The role of carbides in the synthesis of hydrocarbons has been widely considered ever since the carbide theory was first postulated by Fischer and Tropsch in 1926 (20). Although recent experimental studies indicate that the carbide theory is largely incorrect, that is, that bulk-phase carbides are not intermediates in the formation of higher hydrocarbons, iron catalysts converted to Hagg carbide or cementite are usually more active than similar raw or reduced catalysts (21). (For a review of the carbide theory up to 1950, see p. 571 of reference 22.) The selectivity of carbided iron catalysts is essentially the same as that of corresponding reduced catalysts. Nitrides of iron are usually more active than reduced or carbided catalysts, and the catalyst selectivity is significantly different. 

Carbide, iron complex, 26 246 Carbido carbonyl ruthenium clusters. 

C, Carbide, iron complex, 26 246 ruthenium cluster complexes, 26 281-284 CHFiO, Acetic acid, trifluoro-, tungsten complex, 26 222... 

Conversion of the bulk of the catalyst metal to carbide during hydrocarbon synthesis is only observed in the case of iron catalysts. The carbide formation, which occurs parallel with the activity of iron catalysts, may have an important influence on the conditions of the catalyst structure and catalyst surface. The carbide formation, however, seems to be insufficient for the catalyst activity. Treatment of carbided iron catalysts with sulfur does not change the carbide content but makes the catalyst inactive for hydrocarbon synthesis (134). 

Chemical industry, e.g., phenol-formaldehyde resin, catalysts, PVC emulsion-type, amino acids, etc. Ceramic industry, e.g., aluminum oxide, carbides, iron oxide, kaolin, etc. 

C, Carbide, iron complex, 26 246 ruthenium cluster complexes, 26381-284 CHF3O3S, Methanesulfonic add, trifluoro-, iridium, manganese, and rhenium com-iriexes, 26 114,115,120 platinum complex, 26 126 CHOS2, Dithioaubonic add, 27 287 CH2> Methylene, osmium complex, 27 206 CH2O2, Formic add, rhenium complex, 26 112... 

Ceramic industry, e.g., aluminium oxide, carbides, iron oxide, kaolin, etc. 

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