Carbon monoxide-hydrogen catalytic

Hydroformylation. Probably the best known catalytic carbonylation reaction is the hydroformylation, or 0x0 reaction, for producing aldehydes and alcohols from carbon monoxide, hydrogen, and olefins (eq. 9) (36). 

Most low-valence metal complexes are generally deactivated by air and sometimes also by water. Carbon monoxide, hydrogen cyanide, and PH3 frequently act as poisons for these catalysts. Poisoning by strongly co-ordinating molecules occurs by formation of catalytically inert complexes. An example is the poisoning of Wilkinson s catalyst for alkene hydrogenation ... 

See Other CATALYTIC IMPURITY INCIDENTS Carbon monoxide, Hydrogen... 

After this preliminary study, we measured the rates of methane reaction with steam (i.e., r values in the r+ > r region), and the rates of carbon monoxide hydrogenation [i.e., ( —r) values in the r+ < region] at 470, 530, 600, and 700°C (84). In these experiments the PCH4 and Pco values did not exceed 0.2 and 0.1 atm, respectively therefore, (27 7) and (278) were applicable. Variations in catalytic activity were taken into account on the basis of control experiments. 

In this chapter, recent results are discussed In which the adsorption of nitric oxide and its Interaction with co-adsorbed carbon monoxide, hydrogen, and Its own dissociation products on the hexagonally close-packed (001) surface of Ru have been characterized using EELS (13,14, 15). The data are interpreted In terms of a site-dependent model for adsorption of molecular NO at 150 K. Competition between co-adsorbed species can be observed directly, and this supports and clarifies the models of adsorption site geometries proposed for the individual adsorbates. Dissociation of one of the molecular states of NO occurs preferentially at temperatures above 150 K, with a coverage-dependent activation barrier. The data are discussed in terms of their relevance to heterogeneous catalytic reduction of NO, and in terms of their relationship to the metal-nitrosyl chemistry of metallic complexes. 

A small modification of the above design, in which the catalyst in the form of granules or pellets is placed in an annular basket made of wire mesh fitted close to the reactor wall, has also been examined. The use of such an annular basket-type reactor has been reported by Tajbl et al. (1967), Relyea and Perlmutter (1968), and Lakshmanan and Rouleau (1970). The basic features of this reactor are the same as the ones described above. The reactor has been used to carry out high-pressure, high-temperature catalytic methanation of mixtures of carbon monoxide/hydrogen and carbon dioxide/hydrogen. 

The selective production of methanol and of ethanol by carbon monoxide hydrogenation involving pyrolysed rhodium carbonyl clusters supported on basic or amphoteric oxides, respectively, has been discussed. The nature of the support clearly plays the major role in influencing the ratio of oxygenated products to hydrocarbon products, whereas the nuclearity and charge of the starting rhodium cluster compound are of minor importance. Ichikawa has now extended this work to a study of (CO 4- Hj) reactions in the presence of alkenes and to reactions over catalysts derived from platinum and iridium clusters. Rhodium, bimetallic Rh-Co, and cobalt carbonyl clusters supported on zinc oxide and other basic oxides are active catalysts for the hydro-formylation of ethene and propene at one atm and 90-180°C. Various rhodium carbonyl cluster precursors have been used catalytic activities at about 160vary in the order Rh4(CO)i2 > Rh6(CO)ig > [Rh7(CO)i6] >... 

After having discussed catalytic reactions involving carbon monoxide, hydrogen, carbon monoxide and hydrogen, as well as carbon monoxide and water, this section is dedicated mainly to isomerization and rearrangement reactions and to carbon-carbon and carbon-nitrogen coupling reactions. 

A CATOX unit facilitates the oxidation of carbon monoxide, hydrogen, and volatile organic compounds contained in an air stream such as that emerging from the particle filter in the pollution control system of the CDC. Generally, the air stream is passed through a bed of a catalytic solid that acts very much like that in an automotive catalytic converter. 

Transition metal carbides (mainly of W and Mo) have been shown to be effective catalysts in some chemical reactions that are usually catalyzed by noble metals such as Pt and Pd (ref.1). Their remarkable physical properties added to lower cost and better availability could make them good candidates for substitute materials to noble metals in automobile exhaust catalysis. Hence, for this purpose, we have prepared several catalysts of tungsten carbide and W,Mo mixed carbides supported on y alumina with different Mo/W atom ratios. The surface composition has been studied by XPS while the quantitative determination of catalytic sites has been obtained by selective chemisorption of hydrogen and of carbon monoxide. The catalytic performances of these catalysts have been evaluated in the simultaneous conversion of carbon monoxide, nitric oxide and propane from a synthetic exhaust gas. 

The identification of catalytically active species in FTS is of fundamental importance, as an improved understanding could enable the development of catalysts with increased activity and selectivity. In cobalt- and ruthenium-catalysed FTS, metallic cobalt and ruthenium function as active catalysts. However, in iron-catalysed FTS there are several distinct species generated during the reaction. Due to the lower, or similar, activation energy for iron carbide formation in comparison to carbon monoxide hydrogenation, iron-carbide formation is typically observed in FTS. The formation of several iron-carbide phases have been observed -Fe2C/8 -Fe2.2C (hexagonal... 

The synthesis of methanol from carbon monoxide/hydrogen mixtures is also achieved by a catalytic process according to the following stoichiometric equation (Kasem, 1979 Muetterties and Stein, 1979 Klier, 1984 Lee, 1990 Chadeesingh, 2011) or by way of a carbon dioxide/hydrogen reaction ... 

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