Catalytic performance of iron carbide for carbon monoxide hydrogenation

Novel iron carbide and potassium-promoted iron carbide catalysts were prepared and investigated for CO hydrogenation. The iron carbide showed high activity for CO hydrogenation under high pressures; with the addition of potassium, activity and selectivity to C5+ hydrocarbons were greatly enhanced, and the selectivity to methane was suppressed.     

Catalytic hydrogenation of carbon monoxide over nanostructured perovskite-like gadolinium and strontium ferrites

The catalytic properties of perovskite-like ferrites (A_{n + 1}B_nO_{3n + 1}, where n = 1, 2, 3, …, ∞; A = Gd, Sr; and B = Fe) synthesized via ceramic and sol-gel technology in the hydrogenation of carbon monoxide are studied. The interrelation between catalytic activity, selectivity to olefins and synthetic methods for complex oxide preparation, the number of perovskite layers, crystallite size, composition, and the valence state of iron is established.     

Catalytic hydrogenation of carbon monoxide on RuFe/SiO2 catalysts

The H₂+CO reaction on silica supported Ru, Fe and RuFe catalysts prepared from metal carbonyl clusters has been investigated under atmospheric and 20 bar pressure. According to the change of selectivity values with temperature and with pressure, the participation of surface carbon proposed earlier by several authors seems to be confirmed by this work.

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H₂+CO Ru, Fe RuFe, , 20 . , , , .

     

Hydrogenation of carbon monoxide on platinum metals

Together with methane, methanol is the main product of the hydrogenation of CO in the presence of platinum, palladium, and iridium, applied to Y-Al₂O₃, at atmospheric pressure and temperatures of 473–573 K. Dimethyl ether is also formed on platinum and palladium, while small amounts of ethanol and acetaldehyde are formed on iridium. The hydrogenation of CO in the presence of Rh and Ru leads to the formation of normal C₁-C₅ alcohols and C₂-C₅ aldehydes. Reduction of the energy of the metal-carbon bond in the platinum metals (Pd, Ir, Pt, Rh, Ru) increases their specific catalytic activity with respect to the formation of methane and oxygenated organic compounds, and increases the selectivity for higher alcohols and aldehydes.Translated from Teoreticheskaya i éksperimental'naya Khimiya, Vol. 24, No. 1, pp. 75–81, January–February, 1988.     

The adsorption of carbon monoxide on a platinum electrode

The adsorption of CO from 0.5 M H₂SO₄ solution on platinum has been studied using CO labelled with C-14. The adsorption of CO on Pt occurs in the potential range of hydrogen adsorption as well as in the double layer region. In the whole potential range the rate of adsorption follows first order kinetics. From the surface concentrations and charges for oxidation of adsorbed species it follows that the product of chemisorption consists at least of two kinds of species. One of them is the COOH radical probably formed by the reaction of CO with water.     

Vapor-phase hydrogenation of acetone on applied metals of the platinum group

Ruthenium, rhodium, iridium, and platinum, applied on -Al₂O₃, show a high catalytic activity in the vapor-phase hydrogenation of acetone to isopropanol at 337–393K; under these conditions palladium is inactive. A reaction mechanism has been derived from kinetic measurements, adsorption and thermal desorption data, and IR spectra includes as a limiting stage the reaction of acetone adsorbed on the metal with atomic or molecular hydrogen. The kinetic and thermodynamic characteristics of the reaction have been established. The order of the specific catalytic activity of the metals has been determined, the mechanism of adsorption of alcohols on transition metals has been discussed, and the inhibition of the reaction by isopropanol adsorbed on the Ru catalyst has been interpreted.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 22, No. 6, pp. 698–706, November–December, 1986.     

Manganese oxide carbon fibrous materials

Changes in electrochemical properties and surface morphology of carbon fibrous materials upon modification with manganese oxides under various conditions of their deposition were studied. The composition of manganese oxides was determined. The capacitances of the electrical double layer of manganese oxide carbon fibrous materials in sodium chloride solutions of various concentrations were found. Charging parameters of the modified electrodes were determined.     

The reaction of carbon monoxide with platinum ylids

The platinum(II) ylids [X₂Pt{CH(py)CH₂CH₃}(py)] (X = Cl, Br; PY = pyridine) react with carbon monoxide to give the platinum carbonyls [CO(X₂)Pt{CH(py)CH₂CH₂CH₃}] which lose CO on heating or in solution. The platinum(IV) ylids [Cl₄Pt{CH(py)CH₂CH₃}(py)] and[Cl₂I(CH₃)Pt{CH(py)CH₂CH₃}(py)] also react with CO to give Pt(CO)-ylid compounds.