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A complex of geological and geophysical work was carried out to study fracturing in the Jurassic-Neogene rocks of the Heraclea Plateau, which included a field study of the Georgievsky fault zone, structural and geomorphological analysis; the geophysical complex combined marine seismic and magnetometric studies in combination with ground-based studies using electrotomography, gravimetry and magnetometry. The main object of study was the zone of the deep Georgievsky fault and the feathering tectonic disturbances. As a result of complex studies, the main geological and geophysical criteria for the identification of dangerous fracturing sites have been established: the extremely heterogeneous structure of the upper part of the geoelectric section to depths of 30–40 m according to electrical survey data; seismic data indicate that Miocene limestones have extremely low strength properties in areas of increased fracturing; according to electrical survey data, the water content (humidity) of the upper part of the section changes sharply horizontally; in the karst areas at certain depths, there is a sharp variability in resistivity from the maximum values to the minimum; fracturing develops quite actively under the influence of landslide processes. Especially dangerous are the stretching cracks that occur in areas of positive relief of the base rocks, along which landslide bodies represented by limestones slide.

Russian shelf is one of the most important areas for hydrocarbon forecast and mineral resources development. The main features of the geological structure of the shelves of the Far Eastern seas are discussed in the paper. The most promising basins on the Okhotsk shelf are located around Sakhalin island where the majority of the hydrocarbon fields have been discovered. The Bering and the Japan shelf has not been sufficiently studied by now but nevertheless has high oil and gas potential. The main focus is made on the geological and geophysical data, licensing, lithological and stratigraphic structure, seismic interpretation, oil and gas fields distribution. The structural-tectonic zoning of the entire Far Eastern region has been done in order to identify zones of deep troughs with thick sedimentary cover to predict the sources of hydrocarbon generation.

The Leno-Vilyui basin, consisting of the Vilyui syneclise and the Pre-Verkhoyansk deflection, is made of a thick (more than 10 km) sedimentary rock that has formed over a very long geological history (at least 1 billion years). Almost all of the fields identified here are confined to two gross structures, and gas is predominant in the composition of hydrocarbon reservoirs. Studies show that the main hydrocarbon system (Permian-Cretaceous) in most areas is formed by Permian gas source formations, deposited in continental environments with predominance of type III kerogen. Systems with a significant proportion of liquid hydrocarbons may be associated with areas of predominantly marine sedimentation (Pre-Verkhoyansk deflection) or more ancient (Lower Paleozoic) sediments. In all cases, natural reservoirs are distinguished by a complex structure due to sharp facial variability and intensive secondary transformations.

The history of the formation of multi-level geological education at Moscow State University is presented. The features of independently established educational standards and curricula at the Department of Geology of Moscow State University are considered. The difficulties encountered in the formation of the structure of educational standards, curriculum development, and transition to the system of credits are analyzed. Questions of the formation of the structure of the educational process in Master’s studies based on the Master’s programs rather than on the profile of training, as in a Bachelor’s program are raised.

Outlines the history of the formation of layered geological formations at MSU. The features of independently established educational standards and curricula at the geological faculty of Moscow state University are considered. The difficulties encountered in the formation of the structure of educational standards, curriculum development and transition to the system of credits are analyzed. Questions of formation of structure of educational process in a magistracy on the basis of master's programs, instead of on profiles of preparation, as in a bachelor's degree are brought up.

The efficiency and abilities of the sequence-stratigraphic approach to the integrated interpretation of seismic and well data are considered based on the example of the Lower Nutovo subhorizon of the Odoptu area. The results of this study were used to build a sequence stratigraphic model, a curve of the relative sealevel changes, and a regional chronostratigraphic chart tied to the geochronologic timescale.

The Siberian Platform is unique by its volume of Meso-Neoproterozoic sedimentary deposits. For about one billion years (∼1650–650 Ma) several sedimentary basins were developed here, resulting in the formation of several kilometers thickness of sedimentary cover. The Riphean (Mesoproterozoic–Lower Neoproterozoic) rocks are exposed mainly along platform peripheries. The most complete sections are represented by several megacycles. Each megacycle contains terrigenous series at the base and carbonate formations in the upper part. Several isolated and anisochronous basins were created during the Riphean on the territory of East Siberia. Some of them were intracratonic, others were developed on passive margins. Neoproterozoic orogeny along the platform boundaries resulted in re-organization of the Siberian basins, with extensive faulting, uplifting and erosion of the territories. In eastern Siberia, Riphean series contain large hydrocarbon accumulations. The reservoirs were formed mainly due to fracturing and leaching of carbonate strata (e.g. vugular carbonates of the pre-Vendian weathering crust). The Upper Proterozoic deposits are overlain by thick clayey-carbonate and saliferous-carbonate series of the Upper Vendian and Cambrian, isolating them from the upper sedimentary cover. The Riphean basins contained thick, organic rich, clayey and clayey carbonate. In some of them a hydrocarbon generation maximum took place at the end of the Riphean. The pre-Vendian erosion has removed a significant volume of Riphean sediments. During this time a majority of already formed hydrocarbon accumulations have been lost or degraded. Remaining Riphean series have generated hydrocarbons during the Paleozoic. Despite its complex history, the Riphean is still considered highly prospective, with source rocks developing at multiple levels and reservoirs occurring in both carbonate and clastic rocks. Discoveries of new oil-and-gas fields in East Siberia are likely, but will depend on integration of detailed seismic data and a large volume of core data for the correct prognosis of Riphean reservoir distribution.

The composition and structure of principal key-sections for the Tira (Late Vendian) and Danilovo (Late Vendian-Early Cambrian) Horizons were characterized on the basis of deep-drilling data and studies of natural outcrops along the peripheries of the Kureika syneclise. The typical sedimentary formations/associations were recognized, their vertical and lateral successions were distinguished, and their deposition environments were interpreted. A distribution pattern scheme of thicknesses and depositional environments of Upper Vendian-Lower Cambrian deposits was compiled at the 1: 1000000 scale. The reservoir characteristics of the formations are discussed and forecasted for poorly studied areas of the northwestern Siberian platform.

The catalytic properties and X-ray phase structure of molybdophosphoric heteropoly acid modified with Sb, W, and Nb ions have been studied in the reaction of propane oxidation. The additive of Nb ions increases the total activity of catalyst and its selectivity to acrolein and acrylic acid and decreases the selectivity to propylene. The concentration of Nb ions in samples is varied from 0.025 to 1 mol %. The concentration of Nb ions at a level of 0.025–0.1 mol % has the most profound effect on the reaction selectivity and the yield of mild oxidation products. The reaction selectivity depends on both the concentration of added niobium and the reaction conditions. The growth in the reaction temperature increases the conversion and selectivity to acrolein and reduces the selectivity to acrylic acid and propylene. The use of reaction mixture with higher propane concentrations decreases sharply the selectivity to acrolein. The obtained data can be explained by the possibility of the rearrangement of Nb ions between the cationic and anionic sublattices of heteropoly acids and by the change in the ratio between the acrolein and acrylic acid formation rates. The development and application of heteropoly compounds modified with niobium permits to increase the yield of target products in the partial propane oxidation.

The paper summarizes data on the geology, lithology, and geochemistry of petroliferous Riphean, Vendian, and Lower Cambrian rocks in the central parts of the Siberian Craton. The petrological-geological properties of these sediments have been assessed based on results of paleogeographic analysis of these rocks, discrimination of oil reservoirs and oil-source successions, determination of secondary alterations of the rocks, and sources of oil generation and regional migration of hydrocarbons into various traps in zones of possible oiland-gas accumulation.

The partial oxidation of isobutylene to methacrolein on a multicomponent multiphase Co-Mo-Bi-Fe-Sb-K-O catalyst and on catalysts from which some components were absent was studied. Activity and selectivity changes in the case of isobutylene oxidation were the same as in the oxidation of propylene; however, the rate of propylene oxidation was higher than that of isobutylene oxidation. The X-ray diffraction analysis of the catalysts before and after the reaction indicated the occurrence of a number of phases in the samples: α-CoMoO4, β-CoMoO4, Fe2(MoO4)3, reduced bismuth molybdate species, MoO3, and reduced MoO x species. Under catalytic reaction conditions, redox phase transformations occurred. Iron molybdate and molybdenum oxide phases underwent the largest transformations. Of two molybdenum oxide phases, a β-Mo4O11 phase with a structure of a crystallographic shift is formed in the course of catalysis, whereas the second phase (MoO3) almost does not participate in catalysis and occurs in an excess.

The role of various components of a multiphase oxide catalytic system in the partial oxidation of propylene to acrolein is investigated. Catalytic activity is studied for the Co6–8Mo12Fe2–3Bi0.5–0.75Sb0.1K0.1Ox catalyst, which is taken to be the reference, and for catalysts in which the amount of some component is progressively reduced down to zero. The results obtained provide insights into the role of the components of the catalyst.CoMoO4 forms the structural framework of the catalyst. Iron molybdate can be stabilized on CoMoO4 as β-phase. As its content is increased, the catalyst gains activity but its selectivity declines. Bismuth molybdate is responsible for the selectivity of the process. When present in small amounts, MoO3 raises the selectivity, binds free oxides, and converts reduced molybdates into their oxidized forms. Excess molybdenum trioxide causes a dramatic fall in the catalytic activity. Potassium and antimony decrease the catalytic activity, but even small amounts of these elements raise the selectivity of the catalyst. Chromium can substitute for iron atoms in the multicomponent catalyst. Ni, Mn, and Mg substitute for Fe in iron molybdate to decrease the catalytic activity.

The structures of a complex multicomponent Co-Mo-Fe-Bi-K-Sb-O catalyst for the oxidation of propylene to acrolein and simpler catalysts from which some catalyst components were absent were studied by X-ray diffraction analysis. The phases of α-CoMoO4, β-CoMoO4, Fe2(MoO4)3, Bi2O3 ⋅ MoO3, Bi2O3 ⋅ 2MoO3, Bi2O3 ⋅ 3MoO3, oxidized molybdenum oxide, and reduced molybdenum oxide are the main components of the catalyst. Ternary compounds were not detected. Under catalytic reaction conditions, the relative amounts of the phases changed; this change suggests the occurrence of redox transformations with the participation of these phases, probably, at the interface.

Cobalt- and iron-containing catalysts supported on MgO, ZrO2, γ-, θ-, and α-Al2O3 were synthesized and studied in the CO2 reforming of methane. The CoO/α-Al2O3 systems are the most active and stable. The dependence of the catalytic activity and the degree of reduction on the amount of supported CoO was studied. In the active catalysts, CoO is weakly bound to the support and can readily be reduced to metal cobalt. Coke formed in the course of the reaction does not affect the activity of the CoO/α-Al2O3 catalyst.

The interactions of oxidized and reduced Co/α-Al2O3 (4 wt % CoO) with H2, CH4, CO2, and O2 and their mixtures are studied in flow and pulse regimes using a setup involving a DSC-111 differential scanning calorimeter and a system for chromatographic analyses. It is shown that treatment with hydrogen at 700°C results in the partial reduction of cobalt oxide to Co. Methane poorly reacts with the oxidized catalyst but readily reacts with the reduced catalyst to form H2 and surface carbon. The initial surface carbon transforms into other forms, which block the cobalt surface to different extents and differ in the heats of reaction with CO2. Carbon dioxide may react with the surface carbon to form CO (rapidly) and with metallic Co to form CO and CoO (slowly). Thus, the main route of methane reforming with carbon dioxide on Co/α-Al2O3 is the dissociative adsorption of CH4 to form surface carbon and H2 and the reaction of surface carbon with CO2 to form CO via the reverse Boudouard reaction.

The reactions of oxidized and reduced 6 wt % NiO/α-Al2O3 with H2, CH4, CO2, O2, and their mixtures are studied in flow and pulse regimes using a setup equipped with a differential scanning calorimeter DSC-111 and a system for chromatographic analysis. It is shown that treatment with hydrogen at 700°С results in the partial reduction of NiO to Ni. Methane practically does not react with oxidized Ni/α-Al2O3 but it does react actively with the reduced catalyst to form H2 and surface carbon. The latter is capable of reacting with lattice oxygen of Ni/α-Al2O3 (slowly) and with adsorbed oxygen (rapidly). Carbon dioxide also reacts with surface carbon to form CO (rapidly) and with metallic Ni to yield CO and NiO (slowly). Thus, the main route of methane reforming with carbon dioxide on Ni/α-Al2O3 is the dissociative adsorption of CH4 to form surface carbon and H2 and the reaction of this carbon with CO2 resulting in the formation of CO by the reverse Boudouard reaction. Side routes are the interaction of the products of methane chemisorption with catalyst oxygen and the dissociative adsorption of CO2 on metallic nickel. A competitive reaction of surface carbon with adsorbed oxygen results in a decrease in the CO2 conversion in methane reforming with carbon dioxide. Therefore, the presence of gaseous oxygen in the reacting mixture decelerates methane reforming (catalyst poisoning by oxygen).

Published data on the molar absorption coefficients e and integral intensities A 0 of vibrations in physically and chemically adsorbed molecules are reviewed. Analysis of published data shows that bonds characterized by high values of the dipole momentum derivative with respect to the normal coordinate change during adsorption toward decreasing this derivative, whereas bonds characterized by a low value of the derivative change toward increasing the derivative. Thus, adsorption results in a decrease in the difference in values of the dipole momentum derivative with respect to the normal coordinate of different bonds compared with the same bonds in the individual molecules. In addition, the interval of changing the molar absorption coefficients for the surface complexes are at least two orders of magnitude lower than that for the same bonds in the molecules in the gas phase. A series for the degree of easiness in detecting complexes on the catalyst surface (the series of decreasing the molar absorption coefficient) is proposed.

This paper presents an overview of the plenary lectures and some of the oral and poster presentations at the 4th International Congress on Oxidation Catalysis in Potsdam (Germany). The main topics were the partial oxidation of alkanes and the oxidation of olefins by H2O2. Considerable attention is given to the use of modern physical methods in the mechanistic studies of oxidation catalysis and in the studies of catalyst structures.

Advantages and drawbacks of commercial catalysts for gas-phase hydrogenation are considered. The use of modified catalysts, including nickel catalysts modified with heteropoly compounds, is promising. Data on the selective reduction of carbonyl compounds and hydrogenation of aromatic hydrocarbons over these catalysts are presented. Palladium films are shown to be the best catalysts for the selective reduction of acetylene compounds to olefins.

The catalytic activity, adsorption capacity, and pore structure of low-percentage nickel catalysts supported on γ-Al2O3or activated carbon and modified by tungsten heteropoly compounds are studied. The activity, selectivity, and thermal stability of the catalysts in the vapor-phase hydrogenation of olefins and aromatic hydrocarbons are higher than those for conventional nickel catalysts. The concentration of nickel in the catalysts is 10–15 times lower than that in commercial catalysts. However, the modified catalysts have higher specific surface areas of metal, higher dispersion, a uniform distribution of metal particles, and a pore-radius distribution other than in the support. The study of water adsorption and desorption showed that the heteropoly compound modifying the γ-Al2O3support covers the support surface completely, and supported nickel interacts with the active surface of the modifying agent rather than with Al2O3. A hydrogenation mechanism is proposed, which involves H2dissociation on Ni particles and the subsequent diffusion of hydrogen atoms via a spillover mechanism to the adsorbed organic compound with the participation of the OH groups of the modifying agent.

Temperature-programmed reduction by hydrogen, temperature-programmed desorption of O2, local X-ray spectral analysis, and scanning electron microscopy are used to study redox processes occurring on the Ni–Cr2O3/MgO and Ni/MgO catalysts for carbon dioxide reforming of methane. The reduction of Ni/MgO leads to the formation of nickel clusters distributed over the surface of MgO. During the reduction of NiO–Cr2O3/MgO, chromates are transformed into chromites, and then nickel is formed by the reduction of spinel NiCr2O4. Reoxidation leads to the oxidized structures NiO, NiCr2O4, and NiCrO4.

Catalytic interaction of methane with carbon dioxide with the formation of syngas CO+H2 over manganese oxide containing catalysts was studied. 5%Ca–12%Mn–O/Al2O3 was proved to be the most effective one. At 870°C and space velocity of 900 h−1 the conversion degree of methane was 83.1%, that of CO2 was 62.7%, and the H2-selectivity was 76.5%. The mechanism of methane interaction with Mn-containing catalyst and that of the catalyst reoxidation by CO2 and by O2 was investigated. It turned out that much less of oxygen was introduced into catalyst during oxidation by CO2 than by oxygen. The conversion of CH4 into C2-hydrocarbons takes place under non-stationary conditions. A thermoneutral process of syngas production on Mn-oxide catalyst was proposed using a combination of endothermic CH4+CO2 and exothermic CH4+O2 reactions.

The phenomenon of hydrogen spillover (interphase diffusion of adsorbed hydrogen), the methods for its detection, and the factors influencing it are examined. The common occurrence of the spillover and its role in various adsorption and catalytic processes, particularly in reactions involving hydrogen on multiphase catalysts, are demonstrated. The possible mechanisms of the spillover are analysed. The bibliography includes 189 references.

The NiO and α-Fe 2 O 3 samples from various backgrounds were used as precursors of the catalysts for CO hydrogenation. The effect of the initial microstructure of oxides on the morphological peculiarities and catalytic properties of the newly formed catalysts was studied using transmission electron microscopy and in situ XRD combined on-line with gas-chromatographic analysis. The initial morphology of precursors is found to be responsible for the direction and regularity of the solid-gas reactions yielding the catalyst, as well as for the ‘architecture’ and activity of the catalysts obtained: (i) NiO with the best developed plane (111) transforms into Ni 3 C/NiO catalyst consisting of platelet oxide particle covered by Ni 3 C microcrystals and producing the equal amounts of CH 4 and CO 2 ; disordering of the plane (111) induced by SD + HP leads to the formation of Ni/Ni 3 C/NiO catalyst consisting of the polycrystalline phases, whose catalytic properties improved; (ii) NiO with the best developed plane (100) transforms into Ni/Ni 3 C/NiO catalyst containing NiO microcrystals covered by Ni(100) and polycrystalline Ni 3 C and giving CH 4 as a major product of reaction; action of SD + HP results in the formation of Ni/Ni 3 C/NiO catalyst containing polycrystalline Ni and Ni 3 C phases, whose catalytic properties degraded. Similar correlation is observed for the catalysts prepared from α-Fe 2 O 3 .

The present state of information about the intermediate compounds in heterogeneous catalysis is examined. It is shown that to obtain reliable data on the intermediate compounds it is necessary to use the kinetic data obtained by physical methods in situ and, primarily, IR spectroscopy and also NMR spectroscopy.

A generalized kinetic model, which satisfactory describes the main kinetic features of the gas-phase oxidative coupling of methane over a wide range of pressures and temperatures, was used to investigate the influence of an additional generation of methyl radicals on the process. It was shown that the additional generation of methyl radicals sufficiently enhances the yield of C2 hydrocarbons up to the values obtained with the use of catalysts, but even with a very high rate of additional generation of radicals by means of an effective reaction CH4+O2→CH3+HO2, subsequent gas-phase reactions do not permit to overcome a certain kinetic limit in C2 yield. This is very similar to the results obtained in the catalytic oxidative coupling of methane and it is in good agreement with the assumption that at atmospheric and elevated pressures the main role of most catalysts in this process is an additional generation of methyl radicals.

Catalytic oxidation of C1-C7 alkanes by CO2 as a non-traditional oxidant was studied on oxide catalysts. The supported manganese oxide catalysts are the most active, selective and stable. Methane is converted mainly into synthesis gas. Ethane and propane give products of oxidative dehydrogenation. In the case of C4-C7 alkanes at first direct dehydrogenation takes place and after that reverse water gas shift proceeds. Reactions of carbon dioxide with hydrocarbons were up to now still insufficiently studied. This is caused by small reactivity of both CO2 and hydrocarbons. The recent interest in carbon dioxide reactions is two-fold: 1) the necessity to fight against the so-called green-house effect and 2) the exhaustion of raw carbon material sources [ 1 ]. The CO2 molecule can be used a non-traditional oxidant. The best reducing agent for CO2 is hydrogen. It was shown [2] that methanol synthesis proceeds not by direct CO + H2 interaction, but by preliminary CO transformation into CO2 CO+H 2 O= CO 2 +H 2 After that the interaction of CO2 with H2 gives methanol CO 2 +3H 2 = CO 3 OH+H 2 O But hydrogen is expensive. Hydrocarbons in the role of CO2 reductants are more attractive. The most intensively studied reaction of hydrocarbons with CO2 is methane conversion into synthesis gas CH 4 +CO 2 = 2H 2 OH+2CO The main difficulty encountered when this reaction is used for the practical process of synthesis gas production is coking of the metal catalysts [3–6]. We have studied C1-C7 interaction with CO2 over oxide catalysts [7–10] and it turned out that manganese oxides containing catalysts are effective both for methane transformation into synthesis gas and for C2-C7 alkanes dehydrogenation and oxidative cracking. What is especially important is that these catalysts are very stable during a long period without cake accumulation. This paper provides a review of our work in this field.

The structure of the intermediates surface compounds in heterogeneous catalic oxidation reactions involving molecular oxygen and sulfur is discussed. The degrees of reliability of the role of various proposed structures in catalysis are evaluated. The reaction mechanisms derived from information on the surface complexes are presented. The bibliography includes 141 references.

The structure of intermediate surface compounds in heterogeneous catalytic reactions involving H2, CO, and NO is discussed. The relative reliability of the role of various structures in catalysis is discussed. Schemes for the reaction mechanism which have been developed from information on the surface complexes are described. The bibliography includes 248 references.

Objective: to make a comparative assessment of hemodynamic parameters when correcting combined anesthesia-induced arterial hypotension with dopamine, adrenaline, mesatone, or noradrenaline. Subjects and methods. A prospective study enrolled patients who had undergone prosthetic hip replacement under combined lumbar epidural (ropivacaine)/general (sevoflurane) anesthesia. Intravenous sympathomimetic infusion was initiated when the mean blood pressure decreased below 55 Hg mm. Cardiac index (CI) and systemic vascular resistance index (SVRI) were calculated by impedance cardiography. Fifty-six subjects (14 in each group) were selected for analysis. Results. During the study, CI remained in the normal range for all sympathomimetics. When adrenaline was administered, there was an obvious tendency to maintain blood pressure due to heart rate (HR) with preserved low SVRI. The use of mesatone caused a considerable reduction in HR. No statistically significant differences were found between the dopamine and noradrenaline groups in any of the study stages. The start of infusion of these agents was attended by SVRI normalization and HR maintenance within 60—70 beats per minute. Conclusion. The infusion of dopamine, adrenaline, mesatone, or noradrenaline to correct arterial hypotension resulting from combined epidural block/general anesthesia with sevoflurane ensures maintenance of CI within the normal range. That of noradrenaline and dopamine was ascertained to have a more balanced impact on HR and systemic vascular resistance. Key words: combined anesthesia, epidural block, hemodynamics, sympathomimetics, adrenaline, dopamine, mesatone, noradrenaline.

The structures of the intermediate surface compounds in heterogeneous-catalytic reactions of hydrocarbons, alcohols, and acids, established by spectroscopic (mainly IR spectroscopic) measurements, are examined. The evidence obtained concerning the role of particular structures in catalysis is differentiated: from spectroscopic data obtained before or after catalysis; from spectroscopic data obtained in situ but without kinetic measurements; from spectroscopic data obtained in situ by comparing the kinetics of the heterogeneous-catalytic reactions with the kinetics of the changes in the concentrations of the surface compounds. The mechanisms of heterogeneous catalytic reactions obtained on the basis of the available information about the surface complexes are presented. The bibliography includes 89 references.

The phenomenon of hydrogen spillover (interphase diffusion of adsorbed hydrogen), the methods for its detection, and the factors influencing it are examined. The common occurrence of the spillover and its role in various adsorption and catalytic processes, particularly in reactions involving hydrogen on multiphase catalysts, are demonstrated. The possible mechanisms of the spillover are analysed. The bibliography includes 189 references.

The main types of heterogeneous catalysts used for hydrogenation, the methods for their preparation, and the structure and chemistry of their surfaces are considered, as well as the catalytic activity and the mechanism of action in the hydrogenation of unsaturated and aromatic compounds, of CO, and of carbonyl compounds and in the hydrorefining of fuels. Chief attention is paid to supported Ni catalysts, to the methods for their preparation and physicochemical studies, and to the development of novel catalytic systems through modification. A novel type of catalyst for hydrogenation, viz. metal carbides, is described. Some aspects of the mechanochemical treatment of hydrogenation catalysts, including in situ methods, are discussed. Sulfide catalysts for hydrotreating are also discussed in detail. The bibliography includes 340 references.

The three principal paths of the partial oxidation of methane, to give methanol, formaldehyde, and synthesis gas, have been reviewed. The kinetics and mechanism of the processes have been described. The possible oxidation of methane using different oxidising agents — oxygen and carbon dioxide — has been examined. The bibliography includes 139 references.

Possible ways of increasing the efficiency of catalysts for the oxidative condensation of methane by increasing the pressure, adding other gases to the reaction mixture (methane + oxygen), and carrying out the process under cyclic redox conditions have been examined. In some cases the yield of C2-hydrocarbons can be increased to 32%. The bibliography includes 102 references.

Reoxidation of Mn-containing catalysts by oxygen and carbon dioxide in the conversion of C1−C2 alkanes has been studied. Reoxidation of these catalysts by carbon dioxide and oxygen added at a certain ratio permits to obtain optimum degree of surface oxidation, ensuring the high selectivity of conversion of C1−C2 alkanes to C2H4.