Metal monoxide over

In the refining of the Group V metals (which are more accurately represented as metal-carbon-oxygen alloys), carbon deoxidation is not the only method by which oxygen is removed, because sacrificial deoxidation also occurs simultaneously. The relative extents to which each of these two deoxidation modes contributes to the overall removal of oxygen can be assessed by calculating the ratio of the vapor pressures of carbon monoxide and the metal monoxide over the M-C-0 alloy. The value of this ratio for vanadium at 2000 K is given by the expression... 

Nickel tetracarbonyl Ni(CO)4 was the first metal carbonyl to be discovered, by Mond in 1890 it is obtained by passage of carbon monoxide over nickel metal heated to 320 K. It is a volatile, toxic liquid (b.p. 315 K), and has a tetrahedral structure. It has considerable stability, but inflames in air it is believed that in the structure... 

After combustion of the sample and carriers in an oxygen stream, reducing conditions are achieved by a flow of carbon monoxide over the sample ash. Arsenic, zinc, cadmium, and any remaining selenium and mercury are reduced to elemental form. When the sample is heated to 1150°C in a slow carbon monoxide stream in a quartz tube in a furnace, recovery of all five elements in the liquid nitrogen trap is complete in 30 min. The recovery trap is washed with nitric acid to dissolve all the metals, and the radioactivity of a nitric acid solution of the products is counted with a Ge(Li) detector. 

J) Ichikawa, M., Sudo, M., Soma, M., Onichi, T., Tamaru, K. Catalytic Formation of Hydrocarbons (Ci-Cs) from Hydrogen and Carbon Monoxide over the Electron Donor-Acceptor Complex Films of Alkalimetals with Transition Metal Phthalocyanines orGraphite. J. Am. Chem. Soc. 91, 1538 (1969). 

In 1975 Vannice published a comprehensive study of the kinetics of the methanation of carbon monoxide over various metals.45 He analysed his results in terms of a rate-determining step for the reaction involving the interaction of adsorbed CHOH species and adsorbed H atoms ... 

Dynamic reactor studies are not new, but they have not been widely used in spite of the fact that they can provide a wealth of information regarding reaction mechanisms. In this research, oxidation of carbon monoxide over supported cobalt oxide (C03O4) was studied by both dynamic and conventional steady state methods. Among metal oxides, cobalt oxide is known to be one of the most active catalysts for CO and hydrocarbon oxidation, its activity being comparable to that of noble metals such as palladium or platinum. 

LOW TEMPERATURE OXIDATION OF CARBON MONOXIDE OVER ALKALI-METAL PROMOTED PALLADIUM-TIN OXIDE CATALYSTS... 

CO. For that matter, in regards to predicting the type of electrical behavior, one has to be careful not to place excessive credence on actual electronic structure calculations that invoke the independent electron approximation. One-electron band theory predicts metallic behavior in all of the transition metal monoxides, although it is only observed in the case of TiO The other oxides, NiO, CoO, MnO, FeO, and VO, are aU insulating, despite the fact that the Fermi level falls in a partially hUed band. In the insulating phases, the Coulomb interaction energy is over 4 eV whereas the bandwidths have been found to be approximately 3 eV, that is, U > W. 

P. Salomonsson, T. Griffin, and B. Kasemo, Oxygen desorption and oxidation-reduction kinetics with methane and carbon monoxide over perovskite type metal oxide catalysts, Appl CataL A. 704 175 (1993). 

Carbonyl compounds are formed with platinous derivatives, as, for example, by passing carbon monoxide over platinous chloride at 250°. Under these conditions there is obtained a mixture of PtCl - 2 CO, and 2 PtClj 3 CO, which on further heating gives PtClj CO. Other platinous compounds yield similar derivatives. Carbonyl compounds may also be prepared by passing an equimolecular mixture of carbon monoxide and chlorine over platinum sponge or foil at 240°-250°. This reaction is sometimes used to detect the presence of small amounts of rhodium or certain base metals in platinum. ... 

Weller (133) passed carbon monoxide over a cobalt catalyst at synthesis conditions and found high carbon monoxide consumption during the very first moment of the treatment. The carbon monoxide consumption diminished rapidly to a much lower but steady rate. Evidently a flash carbiding of the surface occurred, followed by a slower reaction of the bulk metal. The rate of synthesis is comparable with the initial carbiding rate. Hydrogenation of the cobalt carbide proceeds faster than the carbiding (in contrast to the experiences with iron catalysts). 

In hydrogenation of carbon monoxide over supported catalysts of technetium metal between 270 and 500 °C in a helium flow, predominantly methane was formed. The conversion of CO into methane increased with increasing temperature. Conversion yields up to 100 vol% of CH4 were obtained over a TC/7-AI2O3 catalyst [23]. 

Now warm the tube C gently with a flame until it is just too hot to touch—between 60 and 100 —and increase the flow of carbon monoxide. Nickel carbonyl vapor is carried over and decomposes in C, depositing a mirror of nickel on the surfaces. The principle of the Mond process for purifying nickel is to pass carbon monoxide over the metal and then to decompose the nickel carbonyl on the surface of heated nickel balls. Cobalt, the main impurity to be removed, does not react with carbon monoxide under these conditions, and in any case its carbonyl is not volatile. Nickel completely free from cobalt is thus obtained. 

Self-sustained rate oscillations have been observed in many heterogeneous catalytic reactions. The largest amount of information on kinetic self-sustained oscillations was obtained for the oxidation of carbon monoxide over noble metals, particularly by the group of Ertl, who in 2007 received a Nobel Prize in Chemistry for his work regarding this phenomenon. 

The most appealing and promising strategy, however, is the carhonylation of amines and/or nitro compounds with carbon monoxide over transition metal complexes, which permits the use of safer raw materials. These reactions are catalytic and do not produce large amounts of saline by-products [34, 35]. 

Royer S, Duprez D Catalytic oxidation of carbon monoxide over transition metal oxides, ChemCatChem 3 24-65, 2011. 

Cant, N., Hicks, P. and Lennon, B. (1978). Steady state oxidation of carbon monoxide over supported noble metal catalysts with particular reference to platinum, J. Catal., 54, pp. 372-383. Taylor, K. (1984). Catalysis, Science and Technology, J. Anderson and M. Boudart (eds), Vol. 5. Springer Verlag, Berlin, p. 119. 

Engel, T. and Ertl, G. (1979). Elementary steps on catalytic oxidation of carbon monoxide over platinum metals, Adv. Catal., 28, pp. 1-78. 

The oxidation of carbon monoxide over a base metal catalyst was selected because it is a highly exothermic reaction whose rate has an approximate first order dependence on the concentration of... 

Ceint NW, Hicks PC, Lennon BS (1978) Steady-state oxidation of carbon monoxide over supported noble metals with particular reference to platinum. J Catal 54 372-383... 

As wc know, carbon nanofibers have been widely used in various areas, such as in electronic components, as polymer additives, for gas storage, and as catalyst support [94]. Via the decomposition of hydrocarbons or carbon monoxide over Ni, Co or Fe catalysts, a large quantity of carbon fibers can be produced. Moreover, these carbon fibers with different sizes and shapes, such as straight, bent, thin and helical, etc., could be synthesized by controlling the reaction conditions [95-99]. With carbon nanofibers as template, Ueda and co-workers prepared a number of single and binary transition metal oxide nanofibers and/or nanotubes, including LaMnOs and LaFeOs nanofibers and nanotubes [99-102]. 

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