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The catalytic system Ru/MgO has been characterized by TEM and XPS in the Ru 3d, Cl 2p and O1s regions. It was shown, that the treatment of the sample with H₂ at 450 °Ñ leads to reduction of supported Ru (III, IV) chloride complexes to Ru metal crystallites of 2–5 nm in size (the surface atomic ratio Ru : Cl of reduced sample is 6.2). The shift of Ru 3d peak (279.5 eV) to lower bond energy (BE) found for Ru/MgO sample as compared with bulk Ru metal (280.2 eV) is proved to be due to the differential charging effect. The value of this effect was estimated by a comparison of the valence band spectrum of supported Ru particles with that of bulk Ru. Taking the differential charging into account, the "true" value BE of Ru 3d_5/2 (280.5 eV) was determined. The shift of Ru 3d peak towards the higher BE values may indicate the electron-withdrawing effect of MgO surface to supported Ru particles.

A change in the ratio between monomeric and polymeric molybdenum species regarding the concentration and pH of the impregnation solutions will probably make a significant effect on the nature and number of active sites of Mo/ZSM-5 catalysts. To provide the control of molybdenum species in solutions, we have studied the dependence of structure of molybdenum species in the initial impregnation solutions of ammonium heptamolybdate on the concentration and pH of these solutions (from electron absorption spectra). When the concentration of solutions is low or pH increases, there are no polymeric molybdenum species. Besides, there is a region where monomeric and polymeric species exist at a time. At higher concentrations or when pH decreases, monomeric species transform almost completely into polymeric species.

In the present work adsorption of NO and coadsorption of NO, CO and O₂ has been investigated by means of thermal desorption spectroscopy (TDS) and temperature programmed reaction (TPR). Influence of adsorbed oxygen on morphology of Pd-nanoparticles as well as Pd(110) plane was studied by the theoretical method of interacting bonds (MIB). It has been shown that adsorption of atomic oxygen induces the morphology changes of Pd-nanocrystals and Pd(110) plane. By analysis of TPR spectra of desorbing N₂ and CO₂ for different NO_ads + CO_ads coverages, we suggest an autocatalytic reaction in an "explosive" way. The addition of oxygen was found to inhibit the process of NO dissociation. Exposure of NO and CO on oxygen pre-adsorbed layer results in appearing of low-temperature peak of CO₂ in TPR spectra at 265 K.

The development of civilization is inevitably connected with the increase of energy consumption. Nowadays the main part of energy is produced through incineration of organic fuel, the products of fuel combustion (CO₂) being discharged into atmosphere. However the ecological problems impelled the world community to intensify their activity in order to decrease CO₂ emission. There is a great number of known chemical reactions, both catalytic and non-catalytic, which bound CO₂ chemically into various products. Specifically, the processes of hydrogen reduction of CO₂ may proceed with the production of methanol, dimethyl ether (DME), methane, light hydrocarbons, or liquid motor fuels. Among these, the processes of motor fuel production on the bi-functional catalysts are most likely to be industrially applied in a large scale. The scientific and technological aspects of the processes of hydrogen reduction of carbon dioxide are considered with regard to CO₂ utilization. The influences of the catalysts composition, pressure, temperature, (H₂–CO₂)/(CO + CO₂) ratio, duration of the test run (up to 1000 h) on the activity and selectivity of the bi-functional catalysts in the synthesis of liquid motor fuels were studied. Depending on the composition of the liquid organic products, utilization of carbon in CO è CO₂ comprised 70 to 90%.

The comparative study of Fe-, Mn- and Cu-oxide catalysts supported on α-Al₂O₃, TiO₂, CeO₂ and pure graphite-like porous carbon Subunit in the catalytic wet peroxide oxidation by hydrogen peroxide in a stirred batch reactor at 90 °C was performed. The Fe-containing samples supported on α-Al₂O₃ are sufficiently active and most stable and selective in respect to the CO₂ evolution. Cu-containing catalysts are most active, Fe-containing catalysts appear to be much more stable and ecologically benign. The pure Subunit has shown an appreciable activity and highest selectivity in respect to CO₂. Hydroquinone and pyrocatechol have been found in the liquid phase as intermediates of the oxidation. Kinetics of the change of the phenol, hydrogen peroxide as well as intermediates concentration has been recorded. The oxidation of phenol over Subunit is assumed to occur via a mechanism, which is different from that for the oxide catalysts.

Iron-containing catalysts promoted by nickel or cobalt were tested in methane decomposition reaction at low temperature (600–650 °C) and pressure 1 bar in order to study their catalytic properties and to produce catalytic filamentous carbon (CFC). Catalyst preparation method and composition of the catalysts were found to influence their properties. It was found, that introduction of cobalt or nickel in small amount (3–10 % mass) results in the magnification of carbon yields 2–3 times in comparison with Fe-Al₂O₃. Investigations of Fe-Co-Al₂O₃ and Fe-Ni-Al₂O₃ catalysts genesis were performed by Mössbauer spectroscopy, XRD, TEM. It is established that Co or Ni additives render activating influence on Fe catalysts which become apparent in decrease of the methane decomposition temperature and the formation of multiwall carbon nanotubes (MWNTs).

Ni, Pt, lanthanum nickelate with and without Pt supported on corundum carrier either pure or promoted with CeO₂–ZrO₂ were tested in partial methane oxidation (POM) to synthesis gas under conditions (high temperature, short contact time, highly diluted gas mixture, small catalyst grains) providing studying of the intrinsic kinetics. The phase composition and reducibility of catalysts were characterized with XRD and TPR technique. The influence of catalyst composition on the catalyst performance has been studied. The self-sustained oscillations of methane conversion and products concentration have been observed. The nature of those oscillations is discussed taking into account the intrinsic properties of the catalysts clarified with TPR and XRD.

In the present work, some data on catalytic combustion of one of the most widespread vegetative remainders – rice husk are adduced. The rice husk is used not only as a fuel, but also as a source of silicon for semiconductor industry, the synthesis of silicon carbides and silicon nitrides, etc. We studied the rice husk oxidation in the vibrofluidized bed of either a catalyst or an inert material in conditions allowing to reproduce with an adequate accuracy the data on scraps combustion in the dense and unloaded phase of the fluidized bed. It is found that the process of the rice husk combustion is localized completely in the bed of the catalyst. In the bed of an inert material the process occurs in a space above the bed; consequently, exhausts contain a fair quantity of CO. Studies on solid products of the rice husk combustion have shown that their texture is determined mainly by silica, which is contained in rice husk as amorphous silica SiO₂ × nH₂O. The adsorption ability of these solid products in respect to methylene blue (MB) is investigated. With increasing the process temperature, the value of limiting MB adsorption by the solid products passes through a maximum at the process temperature 600 °C. It is found that the values of the limiting MB adsorption for the solid combustion products in the bed of the catalyst exceed those for solid products obtained in the bed of an inert material. Under discussion are also some distinctions of the process of rice husk processing in the vibrofluidized beds of either catalyst or inert material.

The present paper reviews the processes of separation of microspheres from fly ash and their possible applications for the creation of catalytic supports, adsorbents and catalysts. To isolate magnetic microspheres and cenospheres of stabilized composition, the process flowsheets of concentrate separation, based on the combination of hydro- or aerodynamic and granulometric classification, followed by the separation in magnetic field of different intensity, were developed. Novel materials based on cenospheres of stabilized composition, such as mesoporous microspherical glasses (specific surface area S_sp = 3–50 m²/g), the supported iron oxide systems (S_sp = 50–200 m²/g), and zeolites are described. Spherical zeolites demonstrated good ion exchange properties of in cesium and strontium removal from the technological solutions. The catalytic properties of Fe₂O₃/cenosphere catalysts and magnetic microspheres in deep oxidation of methane are discussed.

The capability of combustion of solid fuels (such as the brown coal of the Kansk-Achinsk coal deposit) in the fluidized bed of an inert material in the presence of unmovable catalytic packages is investigated. This arrangement of the catalytic process is shown to allow the achievement of the same parameters of the fuel burn off and the content of toxic substances in the flue gas as in the case of fuel combustion in the fluidized bed of catalyst grains. The new arrangement of catalytic processes can be recommended for the accomplishing of some other exothermic catalytic reactions which require the maintenance of isothermal conditions.