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Catalysts based on manganese oxides, doped with Pt, and supported on ceramic monoliths with a honeycomb structure were produced by impregnation and solution combustion synthesis (SCS). In SCS, glycine was used as a fuel additive, ensuring different conditions of the combustion of depleted (φ 1) fuel mixtures. The catalysts were studied by TGA, XRD, HRTEM, TPR-H2, BET, and differential dissolution. The catalytic properties of the samples were investigated in the deep oxidation of butane and methane. It was shown that, under SCS conditions, the active components form as a finely dispersed particles of metallic platinum and manganese oxides Mn3O4 in the near-surface layers of the support. Unlike this, after the thermal treatment of the impregnated catalyst, the formed manganese oxides are enriched with Mn(IV) cations and primarily localized in the bulk of the support, forming with it an interaction phase. The high activity of the SCS catalysts in the oxidation of butane and methane is manly determined by the presence of reduced forms of manganese oxide and the accessibility of the active components for the reactants in the near-surface layers of the support.

The morphological and structural properties of Pd–CeO2/Al2O3 catalytic compositions annealed at 100, 500, and 1000°С are studied, along with thereof coatings deposited on metallic foil via cold gas dynamic spraying. The influence of the preparation technique of the initial catalytic composition and introducing active component into a coating on their phase states, particle sizes, and activitites is elucidated. It is shown that introducing active components via impregnation into preliminarily sprayed alumina layer ensures the uniform distribution of Pd and Ce in the support profile, the formation of nanosized PdO particles, and the phase of interaction between the components of the catalyst and support. The impregnated catalyst shows the highest activity in the reaction of methane oxidation. The technique for preparing coatings has no limitations when scaled up and can find application in manufacturing full-size catalysts on metallic foil for different types of power engineering devices.

Catalysts containing Mn, Mn–La and Mn–Ce oxides supported on ceramic honeycomb monoliths were prepared by excess-wet impregnation and solution combustion synthesis (SCS). In SCS, glycine was used as a fuel additive with variable concentration (fuel lean and fuel rich conditions). The catalysts were studied by BET, XRD, HRTEM, H2-TPR, and differential dissolution. Properties of the catalysts in the deep oxidation of butane were investigated. The best activity and stability were observed for the catalysts prepared by SCS under fuel rich conditions. Under these conditions, the active component is formed as highly dispersed particles of manganese oxides in the composition of simple and mixed oxides that are located in subsurface layers of the support. On the contrary, manganese oxides that are formed upon thermal treatment of the impregnation catalyst are located mostly in the bulk of the support. Reducing conditions of the SCS reaction lead to the formation of simple and mixed oxides where manganese is mostly in Mn3+ and Mn2+ oxidation states. The presence of reduced manganese species in the subsurface layers of support, which are accessible to reactants, provides high efficiency of SCS catalysts in the oxidation of butane.

Morphologies and structures of catalytic compositions and coats based thereon were studied using Pd-CeO2/Al2O3 calcined at 100, 500, 1000 °C and the coats prepared by gas dynamic cold spraying onto a metal foil. It was established that the methods for preparation of the initial catalytic composition and for introduction of the active components to the coat influenced the phase composition, particle size and activity to oxidation of methane. The introduction of the active components by impregnation of the pre-deposited alumina layer was shown to provide the uniform distribution of Pd and Ce through the support profile, formation of nanosize PdO particles and of the interacting phases between the catalyst and support components. The impregnated catalyst was most active to oxidation of methane. The method for preparation of the coats has no limitations in scaling-up and, therefore, can be widely used for production of full-size catalysts on metal foils to be used for various energy devices.

Huge amounts of nuclear waste, including depleted uranium, significantly contribute to the adverse environmental situation throughout the world. An approach to the effective use of uranium oxides in catalysts for the deep oxidation of chlorine-containing hydrocarbons is suggested. Investigation of the catalytic activity of the synthesized supported uranium oxide catalysts doped with Cr, Mn and Co transition metals in the chlorobenzene oxidation showed that these catalysts are comparable with conventional commercial ones. Physicochemical properties of the catalysts were studied by X-ray diffraction, temperature-programmed reduction with hydrogen (H2-TPR), and Fourier transform infrared spectroscopy. The higher activity of Mn- and Co-containing uranium oxide catalysts in the H2-TPR and oxidation of chlorobenzene in comparison with non-uranium catalysts may be related to the formation of a new disperse phase represented by uranates. The study of chlorobenzene adsorption revealed that the surface oxygen is involved in the catalytic process.

Cold gas dynamic spraying was used to obtain coatings based on γ-Al2O3 and Pd-CeO2/γ-Al2O3 catalyst on a stainless steel foil. The coatings were studied by thermal cycling, BET, SEM, TEM, and XPS methods. The textural and adhesion characteristics of the coatings were found to depend on the composition of initial alumina powders with metallic aluminum (weight ratios of the components were varied from 2:8 to 8:2). It was shown that a mixture containing 25% γ-Al2O3 and 75% Al provides the optimal properties of the coatings. The effect produced by a method of the active component introduction into the coating on the catalytic properties of samples was examined. A considerable advantage of Pd introduction by impregnation in the preliminarily sprayed γ-Al2O3 layer over the direct spraying of the finished catalytic composition on the foil was demonstrated.

The catalytic activity of nanostructured low percent (1%) Co-Ni catalysts on the basis of glass fiber (GF) prepared by a “solution combustion” (SC) method was studied. The catalytic activity of the prepared samples was studied in the reaction of dry reforming of methane (DRM) with CO2. The obtained samples were characterized by a number of physico-chemical methods, including XRD, SEM, TEM, TGA and AFM. The active component was shown to be dispersed in the near-surface layer of the support as nanoparticles of 10–20 nm in size. The active component showed a Co3O4 or (Co, Ni)Co2O4 spinel structure, depending on the catalyst composition. The spinel structure of the active component interacted strongly with the carrier, providing resistance to carbonization, high catalytic activity toward DRM, and high activity and stability in oxidation reactions.

Platinum nanoparticles supported on nitrogen-containing carbon nanofibers (10% Pt/N-CNFs, [N] = 0–7.5 wt.%) were synthesized and investigated. X-ray diffraction (XRD) analysis and transmission electron microscopy (TEM) demonstrated the formation of 2–9 nm platinum nanoparticles on the N-CNF surface. Platinum nanoparticles were found to be in a metal state experiencing a strong effect of N-CNFs. Testing of catalytic activity in CO oxidation showed that a nitrogen content in N-CNFs exceeding 3.4 wt.% substantially enhances the low-temperature activity characterized by a reaction ignition temperature of ca. 60 °C; however, the enhancement of catalytic activity is non-monotonic with respect to nitrogen concentration in N-CNFs.

Fiber glass supported nanosized Co and Co-Ni catalysts were prepared by solution-combustion synthesis and characterized for their structure and catalytic activity.

Synthesis of alumina-supported uranium oxide catalysts and their characterization in methane oxidation have been performed. The catalysts containing 5% U were prepared by impregnation, solid-phase synthesis and mechanical mixing techniques. Samples were studied using BET, XRD, HRTEM and XPS methods. It was shown that physicochemical properties and activity of the catalysts depend on the preparation procedure and calcination temperature and are determined by the extent of the interaction between active component and support. Most active are the catalysts prepared by impregnation of alumina with an aqueous solution of uranyl nitrate. It was found that the 5%U/Al 2 O 3 catalyst calcined at 1000 °C has the highest catalytic activity, and it is explained by the formation of highly active nanodispersed state of uranium on the surface of the support.

The technology of methane combustion in small gas turbine catalytic combustors on alternative granulated catalysts with a low content of noble metals has been developed and studied. The operations of catalyst packages for environmentally clean combustion consisting of one-, two- or three catalysts with different chemical composition, shape and size of granules have been analyzed. The optimized design of a three-stage catalyst package with total height of 340 mm includes 40mm of highly active Pd-Ce-Al 2 O 3 at the entrance of the combustion chamber in the form of 7.5 mm x 7.5 mm x 2.5 mm rings; 240mm of a basic catalyst based on Mn-hexaaluminate with the granules of the same form and size; and 60mm of Pd―Mn―La―Al 2 O 3 catalyst as 4-5 mm spherical granules at the exit of the combustion chamber. Such optimal design yielded methane combustion over 99.97% at T inlet =470―580 °C and oxygen excess coefficient 5.2-7.0. The emission levels were NO x < 1 ppm, CO < 10 ppm, HC < 10 ppm. The pressure drop across the catalyst package was less than 4% of the total pressure (1 bar).

Modeling of methane combustion in several types of catalyst packages composed of 2 or 3 beds of granulated catalysts with different chemical compositions, shapes and sizes of pellets has been performed. It has been shown that the high efficiency of methane combustion (>99.97%) and low emission of HC < 10 ppm can be achieved for all types of catalyst packages at variation of the inlet temperature. Experimental runs in a model reactor (1.3 kg catalyst) have demonstrated very good correlation with the results of the modeling.

The possibility of preparing honeycomb monoliths from unconventional materials with high adsorption capacity, such as carbonized rice husk (CRH), was studied. Two schemes including modification of the porous structure by silica leaching were suggested for preparation of the monoliths: (1) preparation of CRH monoliths with the addition of Ca-montmorillonite (Ca-M) followed by leaching and (2) preliminary leaching of initial components followed by monolith extrusion. Chemical and textural properties of the materials were studied at each preparation step. The effect of temperature of rice husk (RH) pyrolysis and conditions of leaching treatment on the physico-chemical properties of CRH was investigated. By the data of nitrogen adsorption and SEM characterization, CRH has low specific surface area, pore volume less than 0.1 cm3/g, and composed mainly of macropore channels 5–10 μm in diameter, micropores less than 17 A in size, and a minor amount of mesopores. Treatment of the carbonized product with a 12% solution of potassium hydroxide at 80–100 °C leads to a 90–95% leaching of SiO2 from the CRH composite and increases the specific surface area to 400 m2/g and pore volume to 0.4 cm3/g due to formation of mesoporous structure. The feasibility of CRH honeycomb monoliths preparation and applicability of silica leaching from the monolith material for modification of the porous structure are demonstrated. The resulting monoliths are characterized by specific surface area exceeding 300 m2/g, pore volume 0.3 cm3/g, and high mechanical strength.

Catalysts based on uranium oxides were systematically studied for the first time. Catalysts containing various amounts of uranium oxides (5 and 15%) supported on alumina and mixed Ni-U/Al2O3 catalysts were synthesized. The uranium oxide catalysts were characterized using the thermal desorption of argon, the low-temperature adsorption of nitrogen, X-ray diffraction analysis, and temperature-programmed reduction with hydrogen and CO. The effects of composition, preparation conditions, and thermal treatment on physicochemical properties and catalytic activity in the reactions of methane and butane oxidation, the steam and carbon dioxide reforming of methane, and the partial oxidation of methane were studied. It was found that a catalyst containing 5% U on alumina calcined at 1000°C was most active in the reaction of high-temperature methane oxidation. For the Ni-U/Al2O3 catalysts containing various uranium amounts (from 0 to 30%), the introduction of uranium as a catalyst constituent considerably increased the catalytic activity in methane steam reforming and partial oxidation.

Fe-based catalysts of different geometry are developed for the purification of coke oven gases: bulk, supported on alumina and supported on alumina silicate monoliths. Adsorption and decomposition of H2S on the catalysts developed are studied. Influence of active component content, type of support material and modification by Mn and Mo on the catalyst activity in de-H2S process is elucidated. Supported monolith catalysts show superior activity over bulk and supported spherical catalysts in H2S decomposition reaction and demonstrate stable operation in ammonia decomposition process during 2 hours at 900 °C giving 100% ammonia conversion.

Catalytic burners for fuel cell power plant reformers are alternatives to conventional flame burners. Their application is expected to provide uniform temperatures in the reformer, efficient use of low-calorific gaseous by products and reduction of pollutant emissions. For testing in the burners, a series of spherical Pd/CeO2/Al2O3 catalysts were prepared. An optimum concentration of ceria providing the highest thermal stability of catalysts was determined. An effect of catalyst activation in the reaction mixture-1% methane in air was observed. A series of Mn containing oxide catalysts on spherical γ-Al2O3 or (γ+Χ)-Al2O3, both pure and doped with La, Ce and Mg oxides were prepared. The catalysts were characterized by chemical analysis, X-ray phase analysis, BET surface area and activity measurements in methane oxidation. A batch of Mn-Mg-La-Al-O catalyst was prepared for further long-term testing in a model reformer with a catalytic burner. A model reformer with a catalytic burner was designed and fabricated for testing in the composition of the bench-scale Fuel Cell Power Plant. Preliminary testing of this catalyst showed that it provided complete methane combustion at the specified operational temperatures over 900 °C.

The physicochemical and catalytic properties of bulk uranium oxides prepared by the thermal decomposition of uranyl nitrate [UO 2 (NO 3 ) 2 ·6H 2 O] and precipitation from an aqueous solution of this salt are reported.

Catalysts that have potential in simultaneous removal of H 2 S and NH 3 decomposition were developed. The monolith supports of high surface area and acceptable mechanical strength based on titania and silica–alumina precursors were prepared and tested. Preparation routine and composition of Mn, Fe and Cu oxides supported honeycomb catalysts have been optimized. Impregnated and washcoated monolith catalysts were tested in ammonia high-temperature decomposition.