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The biotechnological potential of Rhodococcus sp. bacteria for direct selective bioepoxidation of propylene to propylene oxide has been investigated. The kinetics of accumulation of propylene oxide in suspensions of the non-growing bacterial cells has been studied. The effect of propylene oxide produced on biocatalytic activity of Rhodococcus cells has been investigated. The study of bacteria adsorption on various ñarbon-containing inorganic supports has been started to develop efficient adsorbents for Rhodococcus immobilization.

The catalytic activity fluctuations upset the equilibrium in reactions of the hydrogenation of carbon depositions and causes increased coke formation. We propose a method of estimation of the Pt–Re catalysts activity, which allows keeping track of the activity enhancement, and hence provides prolongation of the catalyst service cycle by 20–30 %. The method is based on keeping the catalytic activity at an optimum level using the developed computer system.

The paper concerns the environmentally benign method of catalytic cellulose production by wood delignification over various catalysts using sulfur-free reagents – acetic acid and hydrogen peroxide. The optimum operation conditions (temperature and time of the process, H₂O₂/CH₃COOH and liquor/wood ratios) of abies wood delignification using sulphuric acid as reagent and TiO₂ as catalyst which allow reaching the acceptable yields of cellulosic product with high content of cellulose were selected.

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.