Plasma-catalytic dry methane reforming is an advanced approach for converting methane and carbon dioxide into syngas, hydrocarbons and liquid oxygenates, offering a sustainable pathway for greenhouse gas utilization. Plasma is used to trigger chemical reactions at relatively low temperatures, making it more energy-efficient and environmentally friendly compared to traditional high-temperature methods. In present work, a plasma-driven process of dry methane reforming was performed in dielectric barrier discharge reactor filled with mesoporous catalysts. The catalysts based on mesoporous materials MCM-41, SBA-15 and MCF were synthesized and characterized by the various physico-chemical methods. These catalysts were selected for their high surface area and tailored pore structure, which may assist in enhancing plasma-catalyst interactions, improving conversion efficiency, and promoting selectivity toward desired products. It was shown that Ni-based catalysts mainly promoted syngas and C2H6 formation, whereas Cu-based catalysts favored in liquid oxygenate yield enhancement. Cu-containing catalyst based on mesoporous MCF material has shown better CO2 conversion due to open wide mesopores. The oxygen addition to the CH4/CO2 mixture was studied. It was revealed that both gaseous products and oxygenate yields were enhanced in presence of O2. Methanol yield was increased due to parallel reactions of dry methane reforming and partial methane oxidation.

A process of CO2 decomposition in dielectric barrier discharge reactor using mesoporous CeO2-NiO catalysts was studied. Mesoporous materials of MCM-41, SBA-15 and MCF types were used in this study to investigate the influence of the material structure on CO2 decomposition efficiency. The obtained catalysts were characterized by physico-chemical methods: low temperature N2 adsorption, X-Ray diffraction and X-Ray photoelectron spectroscopy. CO2 conversion, CO yield and CO selectivity as well as energy efficiency and specific energy input were calculated. The comparison of process efficiency was conducted with that in the absence of any catalyst (plasma-only reactor). It was shown that in the presence of Ce-based catalysts, the conversion of CO2 (from 11 to 19

Published data on plasma-assisted carbon dioxide methane reforming using heterogeneous catalysts are analyzed. The pathways of the CH4 and CO2 transformation under the conditions of thermal catalysis, plasma action, and plasma-assisted catalysis are considered. Various types of plasma installations are described. The mechanisms of the formation of oxygenates under the conditions of plasma-assisted catalysis are presented. The process selectivity with respect to final products depends on the ratio of the gases and on the structure, dielectric properties, and composition of the catalysts. The important parameters influencing the oxygenate ratio are the metal oxidation state in the catalyst, kind of metal, and support acidity. The catalyst introduction into the plasma can also lead to negative phenomena, namely, to recombination of radicals into the starting compounds.

The problem of CO2 waste in the atmosphere is a major concern, and methods of CO2 utilization are being currently developed. In the present work, a plasma-catalytic process is applied for CO2 dissociation. A series of MgO and CeO2-containing catalysts were synthesized, and the samples were characterized by: a low-temperature N2 adsorption-desorption analysis, X-ray diffraction, X-ray photoelectron spectroscopy, temperature-programmed desorption of CO2, and X-ray fluorescence spectroscopy. It was stated that under dielectric barrier discharge conditions, the catalyst surface, composition, and phase content remain unchanged. The superior catalytic activity of the MgCe-Al sample is attributed to the combination of weak basic sites and oxygen vacancies on the catalyst surface.

Global warming occurs as a result of the build-up of greenhouse gases in the atmosphere, causing an increase in Earth’s average temperature. Two major greenhouse gases (CH4 and CO2) can be simultaneously converted into value-added chemicals and fuels thereby decreasing their negative impact on the climate. In the present work, we used a plasma-catalytic approach for the conversion of methane and carbon dioxide into syngas, hydrocarbons, and oxygenates. For this purpose, CuCe zeolite-containing catalysts were prepared and characterized (low-temperature N2 adsorption, XRF, XRD, CO2-TPD, NH3-TPD, TPR). The process of carbon dioxide methane reforming was conducted in a dielectric barrier discharge under atmospheric pressure and at low temperature (under 120 °C). It was found that under the studied conditions, the major byproducts of CH4 reforming are CO, H2, and C2H6 with the additional formation of methanol and acetone. The application of a ZSM-12 based catalyst was beneficial as the CH4 conversion increased and the total concentration of liquid products was the highest, which is related to the acidic properties of the catalyst.

A series of CeO 2 –MgO catalysts with different molar ratio was prepared for the plasma-activated CO 2 decomposition to CO and O 2 . The catalysts were synthesized by the sol-gel method and characterized by physicochemical methods (XRD, SEM, XPS, low-temperature N 2 adsorption, CO 2 -TPD). The highest CO 2 conversion (31%) was achieved in the presence of the catalyst with the highest CeO 2 content. The addition of H 2 into a CO 2 decomposition system was also studied. No CO 2 methanation occurred in the presence of synthesized catalysts, though an increase in the CO 2 -to-CO conversion was observed due to an increase of a discharge power in the presence of molecular hydrogen.

A number of catalysts based on cerium oxide have been synthesized to study the process of plasma-catalytic decomposition of CO 2 in a barrier discharge. For the first time, an oxide catalyst MgCe-Al has been compared with samples containing in the composition only cerium oxide or magnesium oxide. It has been established that, in the presence of the MgCe-Al sample, the highest degree of the CO 2 decomposition and highest energy efficiency get achieved. Keywords: barrier discharge, cerium oxide, low temperature plasma, catalyst, CO 2 decomposition.

A number of catalysts based on cerium oxide have been synthesized to study the process of plasma-catalytic decomposition of CO2 in a barrier discharge. For the first time, an oxide catalyst MgCe–Al has been compared with samples containing only cerium oxide or magnesium oxide in the composition. It has been established that in the presence of the MgCe–Al sample, the highest degree of CO2 decomposition and energy efficiency are achieved.

Published data on the plasma-assisted catalytic decomposition of CO2 are analyzed. The use of a catalyst allows the CO2 conversion and the energy efficiency of the process to be considerably increased. The majority of studies deal with the CO2 decomposition in a barrier discharge reactor, which is associated with simple reactor design. Key characteristics of catalysts, influencing the efficiency of the CO2 decomposition in a gas discharge, have been determined. These are the presence of oxygen vacancies in the catalyst structure and the presence of base sites in the sample.

The plasma-assisted process of dry reforming of methane in barrier discharge was studied using new compositions of zeolite-containing catalysts. Catalysts based on Ni, Fe, Co oxides promoted with CeO2 have been synthesize and characterized by low-temperature nitrogen adsorption–desorption, X-ray fluorescence spectroscopy, X-ray diffraction analysis, and temperature-programmed desorption of ammonia. The catalytic activity of the prepared samples on the reaction of the syngas production in gas discharge without additional heating of the reactor was studied. It was found that introduction of a catalyst into the discharge region makes it possible to increase the CH4 conversion from 10 to 16

Reactive adsorption desulfurization of a model fuel containing dibenzothiophene with various adsorbents was studied. Adsorbents based on MCM-41 mesoporous material with supported Ni and ZnO phases were prepared and characterized. The desulfurization activity of the material in a fixed-bed flow-through reactor was compared to that of alumina-based adsorbents. The adsorbent based on MCM-41 considerably surpasses its analog on Al2O3 support in the adsorption capacity in reactive adsorption desulfurization of dibenzothiophene at 350°С, pressure of 2 MPa, and feed space velocity of 1 h–1.

As- and Cl-containing impurities are highly detrimental to sulfided catalysts in hydrotreating processes. To prevent the irreversible loss of activity of the main sulfide catalysts by As and Cl contaminants, a protective double-layered guard bed catalyst is applied. Two types of mesoporous silica supports (SBA-15 and MCF) were used to obtain sorption-catalytic materials. The high specific surface area of the supports allowed for a significant increase in access to the active catalyst centers. The NiMo/SBA-15/Al2O3 and NiMg/MCF/Al2O3 sorption-catalytic materials demonstrated high activity and stability over 48 h for the simultaneous removal of As and Cl. The catalytic materials allowed for reducing the concentrations of As and Cl to less than 0.1 ppm in the diesel fraction under the following conditions: 5.0 MPa pressure, 2.0 h-1 LHSV, 300 L/L H2-to-substrate volume ratio, and 360 °C.

A 31P NMR study was carried out to determine the composition of phosphomolybdic acids (PMA) formed in the reaction of molybdenum oxide and phosphoric acid with Mo/P molar ratio = 12. The molybdenum oxide conversion increases with dilution of the reaction mixture. The major product of this reaction over the entire range of conditions studied was the acid H7PMo11O39. The maximum concentration of H3PMo12O40 acid is achieved when the H2O:MoO3 mass ratio is 10, which is optimal for the preparative synthesis of PMA (84% yield).

Mg, Ca, and Ba catalysts supported on structured mesoporous silica oxides types MCM-41 and Al-SBA-15 were synthesized and investigated in sulfone cracking for sulfur removal from oxidized diesel fuel. Functional materials and catalysts were characterized by low-temperature nitrogen adsorption/desorption, transmission electron microscopy, and inductively coupled plasma atomic emission spectroscopy techniques. Catalytic tests were carried out in fixed-bed and batch reactors with a model compound dibenzothiophene sulfone and oxidized diesel fraction as a feed. MgO/MCM-41 and MgO/Al-MCM-41 possess high activity in sulfone cracking. The sulfur content in the diesel fraction decreases from initial 450 up to 100 ppmw. Catalysts can be regenerated for reuse in several cycles and may be potentially scaled up for industrial applications.

Process of chlorine removal from middle distillates with catalysts based on mesoporous materials was examined. The physicochemical characteristics of supports and catalysts based on SBA-15, Al-TUD, and MCF materials were compared. It was found that the catalyst based on MCF material can diminish the content of chlorine in a light diesel fraction to below 0.3 mg kg–1 at 360°C, pressure of 5.0 MPa, and LHSV of 2.0 h–1.

Possibility of using mesoporous materials for obtaining Ni–Mo sorption-catalytic materials for purification of medium-distillate fractions to remove arsenic-containing compounds was examined. It was shown that, in the course of hydropurification, the acidity of the mesoporous material does not directly affect the extent to which the amount of arsenic in hydrocarbons is diminished. It was found that mesoporous supports of the SBA-15, TUD, and MCF types reduce the content of arsenic to less than 0.5 ppm at 360°C and 50 atm of H2.

The effect of the impregnation stage on the synthesis of NiW sulfide catalysts supported on the ZSM-5 zeolite has been studied. The hydrodearomatization (HDA) of light cycle oil (LCO) in the presence of a catalyst containing nickel and tungsten sulfides as an active phase impregnated onto a micro/mesoporous ZSM-5/SBA-15 support has been conducted. The catalyst has been compared with a commercial AGKD-400 diesel hydrotreating catalyst. It has been found that the impregnation of the supports with a solution containing an oxalic acid additive leads to an improvement in the morphology and composition of the active phase. The deepest hydrogenation is observed at 360°C, 6 MPa H 2 , and a LHSV = 0.5 h –1 . The amount of diaromatic hydrocarbons decreases 12-fold, and the sulfur content decreases by 90%.