Carbon monoxide on iron

Radushkevich LV, Lukyanovich VM (1952) About structure of carbon created at thermal decomposition of carbon monoxide on iron contact. J Phys Chem 26 88-95... 

Iron pentacarbonyl was obtained in 1891 by Ludwig Mond by the action of carbon monoxide on iron, prepared from ferrous oxalate. The yield obtained was about 1% of the theoretical from the iron employed. ... 

Hofer, L.J.E. Sterling, E. and McCartney, J.T. "Structure of the Carbon Deposited from Carbon Monoxide on Iron, Cobalt, and Nickel" J. Phys. Chem. 1955, 59, 1153. 

Now, theoretical calculation methods of sufficient accuracy may fill the lack of quantitative information concerning so elusive species. On the other hand, the use of a monocoordinated complex as being the simplest molecular model to simulate a chemisorption phenomenon on a metallic surface, for instance the chimisorption of carbon monoxide on iron or nickel [16,17,18] enables to predict the shifts of the CO stretching vibration of the adsorbed species. Similar effects observed with cyanide anions CN on a cathode of platinum, silver or gold, using non-linear optics techniques can be rationalized by computing the CN vibration mode of the corresponding triatomic systems [19,20,21]. 

Carbonyl iron or carbonyl iron powder is metallic iron of extreme purity, produced as microscopic spherical particles by the reaction of carbon monoxide on iron ore. This reaction gives a liquid, called iron carbonyl Fe(CO), that is vaporized and deposited as a powder. Carbonyl iron is mainly used for magnetic cores for high-frequency equipment and for pharmaceutical application of iron. 

The HPLP apparatus has been used to study the hydrogenation of carbon monoxide on iron and rhodium polycrystalline specimens as well as on sit e crystals and various rhodium compounds." Postreaction surface analysis revealed the presence of a catalytically active carbonaceous layer on all the samples investigated. In addition, precise control of the rhodium surface oxidation state by oxygen pretreatment in the UHV chamber was found to have a marked effect on the product distribution of the rhodium catalyzed reaction. 

Whiskers and filaments of graphite have also been observed to form during pyrolytic deposition of various hydrocarbon materials. Hillert and Lange " studied the thermal decomposition of n-hep-tane and reported the formation of filamentous graphite on iron surfaces at elevated temperatures. Pyrolysis of methane" and carbon monoxide" on iron surfaces or heated carbon filaments also resulted in the formation of similar structures as well as the thermal decomposition of acetylene on Nichrome alloy wires below 700°C."... 

Henning, C. M. and Natelson, S. Improved methods of analysis for oxygen, carbon monoxide and iron on fingertip blood. Clin. Chem. (1955), 1, 165 - 179. 

The lethal effects of carbon monoxide on hemoglobin had been analyzed by Claude Bernard and shown to be due to the formation of an iron-carbonyl compound. In 1891 Mond and Langer showed that iron pentacarbonyl could be dissociated by light, and in 1897 J.S. Haldane and J.L. Smith found light would decompose the carbonyl compound of hemoglobin. Other metal carbonyls are not photodecomposed. 

The ionisation potential of a core electron depends, to a small extent, on the chemical environment of the atom in question, and chemical shifts of up to about 10 eV can be observed. For example, the C(ls) XPS signal for molecularly adsorbed carbon monoxide on polycrystalline iron at 290 K shows a peak at 285.5 eV, which is... 

Kummer and Emmett 311) studied the chemisorption of carbon monoxide on an iron ammonia catalyst by the same method and found a partial mixing of the desorbed gas, as if the surface consisted of a heterogeneous complex of homogeneous parts. Similar results were obtained by Eischens 312). 

When mixed with air, iron pentacarbonyl decomposes on exposure to sunlight in a very few minutes with formation of carbon monoxide and iron oxide. 

Chin, P., Sun, X., Roberts, G.W., and Spivey, JJ. Preferential oxidation of carbon monoxide with iron-promoted platinum catalysts supported on metal foams. Applied Catalysis. A, General, 2006, 302, 22. 

The mechanism of the reaction which takes place in the presence of nickel as well as certain other of the metal catalysts, has been explained by assuming that metallic carbonyls are formed by the action of carbon monoxide on the metal and that these compounds represent intermediate products in the catalyses. Evidence in support of this theory has been brought forward by Mond, Langer and Quinke,0- who studied the decomposition of carbon monoxide in contact with nickel at temperatures between 350° and 450° C. In examining the carbonized nickel catalyst at the end of the experiment these investigators discovered that when heated, it gave off a volatile inflammable nickel compound which could be condensed to a liquid and which was later identified as nickel carbonyl. Metals, such as nickel, cobalt, and iron, which form distinct metallic carbonyls are particularly active catalysts for the decomposition, a fact which adds weight to this theory. 

The best catalyst was found to consist of zinc oxide and copper (or copper oxide) with an admixture of compounds of chromium. The success of the operation depended upon (a) the absence of alkali, which would cause decomposition of the methanol and the production of higher alcohols and oily products, and (b) the complete elimination of all metals except copper, aluminum and tin from those parts of the apparatus which come in contact with the reacting gases. Contact of carbon monoxide with iron, nickel, or cobalt had to be avoided since they formed volatile carbonyls winch deposited metal, by decomposition, on the active catalyst surface and thereby acted as poisons to destroy activity. 

The only oxide to become consistently more stable as temperature increases is carbon monoxide. On this fact the Iron Age depended virtually any metal oxide is reducible by carbon at a sufficiently high temperature. Visually, this means that the carbon monoxide line moves underneath those of other oxides, as the temperature increases. Thus manganous oxide (MnO) is stable to hot coke up to 1680 K, at which point the lines for MnO and CO meet, and AG° for the reaction ... 

Single-bed catalysts had been used to produce sulfur from dry sulfur dioxide gases. Ryason 1,2) used either Cu, Pd, Ag, Co, or Ni supported on alumina. Khalafalla and Haas (3) optimized the composition of iron-alumina catalysts to produce sulfur from dry gases containing sulfur dioxide and carbon monoxide. Querido and Short (4) demonstrated the feasibility of reducing sulfur dioxide by carbon monoxide on a copper-alumina catalyst at concentrations and temperatures typical of power plant stack gases. 

The objective of this investigation was to examine the effect of water vapor on the reduction of sulfur dioxide with carbon monoxide on an iron-alumina bifunctional catalyst and to devise double-catalyst beds to cope with the deleterious effect of water. The catalyst temperature of the first bed in this double-bed system was varied to adjust the ratio of reactants entering the second bed in order to maximize the removal of sulfurous gases. 

Idakiev et al. [15] also explained the promotional effect of copper. Initially, they investigated the effect of temperature on the activity of 5% Cu and 15% Cu-doped Fe-Cr catalysts. The CO cmiversion increases with increasing Cu loading. Also, the degree of conversimi of carbon monoxide on the unpromoted iron-chromia catalyst sharply decreases with the increase of the space velocity. On the copper oxide promoted samples, it remains almost unchanged. However,... 

The reaction is insensitive to whether the atmosphere used is dinitrogen or carbon monoxide. The iron complex Fe3(PPh3)2 proved to be much less. active than its ruthenium analogue in this reaction. Analyses o-f the gas evolved during the catalytic reactions conducted under dinitrogen have shown the -formation o-f carbon dioxide, but its quantity was less than calculated on the basis o-f the PhNO converted. On the other hand, in protic media the reaction could proceed via the proton trans-fer -from the solvent to n i trosobenzene, with the intermediate formation o-f hydroxyl ami ne s... 

There exist obvious cases where relativistic methods are mandatory such as reactions in which the educts and products feature electronic ground states of different spin. This implies that the spin symmetry is changed on the reaction path (mediated by spin-orbit coupling). Such events occur fairly often in transition metal chemistry (for an example see the recombination of carbon monoxide with iron tetra-carbonyl [1013,1014]), so often that even a new... 

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