The effect of the introduction of catalytically active vanadium(V) atoms on the physicochemical properties of silicotungstic heteropolyacid has been studied. The insertion of vanadium(V) atoms into the framework of monovacant lacunar W-containing heteropolyanions in the form of a H₆V₁₀O₂₈ solution prepared by an environmentally friendly peroxide method has been shown to ensure the formation of a mixed Si-W-V heteropolyanions while maintaining the integrity of the structure. It has been demonstrated that the partial replacement of protons with large cations, such as Cs⁺ and nBu₄N⁺, leads to the precipitation of insoluble acid salts of the composition A_4,5H_0,5SiW₁₁VO₄₀, the properties of which vary significantly depending on the type of introduced counterion (A⁺). The textural characteristics of the synthesized salts have been compared, the TG/DTG/DSC profiles have been obtained, and a phase composition has been analyzed. Characterization of samples after hydrothermal treatment by IR, XRD, and ICP-AES methods has proved the high stability of the synthesized salts. The samples have demonstrated catalytic activity in the oxidation of 5-hydroxymethylfurfural in an aqueous medium, providing the formation of 2,5-diformylfuran with a yield of up to 89%, and the possibility of reusing.

Steam reforming and autothermal reforming of ethanol produce synthesis gas suitable for both powering solid oxide fuel cells and serving as a feedstock for chemical industry applications. For these reactions to occur effectively, heat transfer must be controlled. In the case of endothermic steam reforming of ethanol, the problem of heat transfer from the reactor walls to the catalyst bed arises. For thermoneutral autothermal reforming (steam-air conversion) of ethanol, the problem arises of redistributing the heat released in the front part of the catalyst layer as a result of the oxidation of ethanol with oxygen along the catalyst layer to compensate for the endothermic effect of steam reforming of ethanol. To solve these problems, structured catalysts based on heat-conducting substrates—metal meshes, foam metals, and other supports—are well suited. Such catalysts are a complex composite material with a multi-level structure “structured metal substrate-structural oxide component-active oxide-nanoparticles of metals or alloys”, which combines the functions of a heat exchanger, a flow distributor and the catalyst itself. This work presents the results of the preparation of Pt, Rh, Pd, Ru, Ni, and Co-containing structured catalysts supported on a FeCrAl mesh support and the study of their catalytic properties.

In this work, the catalytic properties of palladium catalysts based on Al₂O₃, SiO₂, their mechanical mixtures with SO₄-ZrO₂ and the Pd/SO₄-ZrO₂-Al₂O₃ catalyst in the hexane isomerization reaction were studied. The catalysts were characterized by low-temperature nitrogen adsorption, X-ray diffraction, transmission electron microscopy, temperature-programmed reduction, IR spectroscopy of adsorbed CO, and XPS. It has been shown that the nature of the palladium support and precursor influences the size and charge state of palladium particles in catalysts. It has been established that the most active in the hexane isomerization reaction are catalytic systems in which positively charged forms of palladium are present.

Ni_xCo_1-xAl₂O₄ (x = 0–0.5) catalysts were prepared by the co-precipitation from solution of Ni, Co and Al nitrates. The dry gel was heated at 700 °C in air and resulting alumina modified by nickel and cobalt ions is formed with spinel structure. The in situ X-ray diffraction study of these precursors in the reduction by a H₂-containing gas mixture at 700 °C and ex situ after preliminary reduction in a H₂-containing gas mixture and further work under reaction medium conditions  showed that ensembles of Ni-Co alloy particles 3-4 nm in size are formed on the spinel surface. The influence of the composition of the catalysts and the duration of their testing on the catalytic properties in the dry reforming of methane reaction (DRM) was studied. The Ni_0.35Co_0.65Al₂O₄ catalyst is stable in the DRM for 20 hours with CH₄ conversion of 76 % and an H₂ yield of 42 % (T = 700 °C, t = 30 ms). The high catalytic activity of the obtained catalysts in DRM is due to the formation of highly dispersed (3–4 nm) nanoparticles of the Ni-Co alloy an active phase in an amount of 17–18 wt. % on the initially large specific surface area of a spinel, stabilized by nickel and cobalt ions, and possessing mobile bulk oxygen under reducing reaction conditions.

Ni_xCa_1-xAl₂O₄ samples, where x = 0.1-0.5, were obtained by co-precipitation followed by drying on air at room temperature. After calcination in air at 700 °C, an oxide compound with a defective structure g-Al₂O₃, in which Ni²⁺ and Ca²⁺ ions are stabilized, as well as highly dispersed fragments of NiAl₂O₄ and NiO was formed. After pretreatment stage (reducing in H₂-containing mixture) and work in the reaction medium, nickel is partially reduced to the metallic state and leaves the structure of the compound, forming on the surface highly dispersed Ni⁰ particles with a size of 3–15 nm. Calcium is stabilized in the structure of g-Al₂O₃ and on its surface. The introduction by Ca²⁺ leads to a significant increase in the concentration of not very stable surface and bulk carbonates and bicarbonates, which promotes the oxidation of C-containing intermediate compounds formed on Ni⁰ centers. In addition, the modification of Ca²⁺ leads to decrease the concentration of strong acid sites on the surface, the formation of a weaker CO₂ bond under reaction conditions, and the fool disappearance of signals from CO complexes with strong LAC, which significantly reduces the amount of carbon, which is formed at the stage of deposition on the surface. The resulting catalysts are characterized by high activity and stable work for a long time in the dry reforming methane reaction.

The effect of operating conditions of ethylene conversion to propylene on the yield of products, activity and stability of NiO-MoO₃/Al₂O₃ catalyst was studied. The catalytic tests were carried out in a fixed-bed flow reactor at temperatures of 100-250 °C, atmospheric pressure and weight hourly space velocity of 0.25-2 h^-1. The maximum propylene yield of 57 wt.% is achieved at 150 °C and 0.25 h^-1. Under these conditions the degree of ethylene conversion reaches 90 %. The kinetic model for the process has been proposed, which described the formation of the main reaction products. It has been shown that carbonaceous deposits are formed on the catalyst surface during the ethylene conversion. The amount of these deposits increases with increasing temperature and contact time. Moreover some Mo species change the oxidation state from +6 to +4/+5.

The influence of the nature of nitrogen-containing compounds introduced into a model cracking feedstock (n-hexadecane) on the composition of regeneration gases formed during catalyst regeneration was studied. An increase in the content of CO and NO_x in the composition of regeneration gases was observed with an increase in the basicity and molecular weight of nitrogen compounds in the range: pyridine < n-butylamine < pyrrole < quinoline < indole. The effect of a Pt-based CO promoter on the composition of regeneration gases was studied. The use of a CO promoter reduces CO emissions by 99.4% but leads to a significant increase in NOx emissions. Additives were synthesized and studied to reduce the content of nitrogen oxides in the regeneration gases of a cracking catalyst. The additives were mixed oxides containing Cu, Fe, Ce, Co, Mn and La deposited on γ-alumina. The use of these additives at the stage of regeneration of the cracking catalyst led to a decrease in the content of nitrogen oxides formed during regeneration. For an additive based on copper oxide, the efficiency of reducing the content of nitrogen oxides in regeneration gases reached 12.2%.

The possibility of introducing nitrogen into the structure of the carbon catalyst support Sibunit by high-temperature treatment in a stream of ammonia at 800-1000°C has been studied. It has been shown that preliminary oxidation of the Sibunit surface with a 5% solution of nitric acid promotes more efficient nitrogen binding, which may be due to the presence of surface oxygen-containing groups and/or greater defectiveness of the surface of the oxidized carbon material. The depositing of palladium to Sibunit, subjected to preliminary oxidation and treatment in NH₃ at 1000°C, leads to an increase in the activity and selectivity of the Pd/Sibunit catalyst in the hydrogenation of acetylene to ethylene. It was found that the improvement in catalytic characteristics is due to an increase in the availability of supported palladium due to its localization in larger pores of the N-modified support.

Catalytic fluidized bed combustion is the most environmentally friendly and energy efficient way of processing various fuels, including low-grade ones. The technology involves the oxidation of volatile substances on the surface of catalyst particles diluted with an inert material in a fluidized bed. The traditional use of quartz sand as an inert material leads to accelerated destruction of the catalyst during operation by attrition. The work is devoted to the study of the effect of magnesium modification of spherical γ-Al₂O₃, used as a carrier for a deep oxidation catalyst (DOC) in a fluidized bed, and the development of an inert material capable of minimizing DOC losses. The modified carrier was obtained by impregnating spherical γ-Al₂O₃ granules with a Mg-containing precursor solution (nitrate and acetate) followed by calcination of granules at 800 °C. The obtained granules were studied by X-ray fluorescence analysis (XRF), inductively coupled plasma optical emission spectroscopy (ICP-OES), low-temperature nitrogen adsorption (BET), scanning electron microscopy (SEM). Their mechanical strength and catalytic activity in CO oxidation were also determined. A linear increase in the strength characteristics of γ-Al₂O₃ was found with the introduction of magnesium from 2 to 9 wt. %. In laboratory conditions, the use of the selected material made it possible to reduce the loss of the catalyst at 4.5 -hour attrition test by 3 times compared with quartz sand.

The list of papers published in 2023