Here is a special issue of the journal, prepared on the basis of reports presented at the anniversary XXV International Conference on Chemical Reactors “ChemReactor-25”. This large-scale event, which took place from October 8 to 13, 2023 in Tyumen, was attended by 230 people from 28 cities of Russia and six countries: Mexico, Great Britain, Netherlands, China, Tajikistan and Kazakhstan. The conference was organized by the Boreskov Institute of Catalysis SB RAS, Tyumen State University and West Siberian Interregional Scientific and Educational Center.

The work proposed a macrokinetic model of first-order CO2 sorption on a 10 mol.% NaNO3/MgO sorbent. Based on the analysis of experimental gravimetric data, the maximum sorption capacity of the sorbent 10 mol.% NaNO3/MgO was determined, which does not depend on the partial pressure of CO2 and at 320 °C is 159% (based on the initial mass of the sample), or 13.4 mmol CO2/ gsorb. The calculated value of the sorption constant kads at temperatures of 280-320 °C and a partial pressure of CO2 of 0.50-0.75 atm is 0.017 min-1 atm-1. Based on the obtained kinetics, a simulation of an adiabatic and isothermal CO2 adsorber was made within the framework of a technological scheme for producing hydrogen 10 kg/h from natural gas at an operating pressure of 12 atm. During the calculations, it was shown that for the effective functioning of the adsorber, intensive removal of the heat released during the sorption process is necessary. This allows CO2 sorption to be carried out for 30 minutes at a temperature of 300 °C and a volumetric flow rate GHSV = 1170 h-1, while the concentration of CO2 at the outlet in dry gas does not exceed 1.5 mol.%.

In this work, we studied the effect of the ratio of Ce and Mn oxides deposited on cordierite ceramics on the structure and catalytic activity in the ozone decomposition at room temperature. The series of catalysts with varying the CeO₂:MnO₂ mass ratios were prepared by impregnation of cordierite ceramic blocks by Ce and Mn nitrates aqueous solutions with the addition of citric acid. The physicochemical characteristics of the catalysts were studied by low-temperature N₂ sorption, X-ray diffraction analysis, scanning electron microscopy, H₂ temperature-programmed reduction. The catalytic activity of the samples in ozone decomposition was tested at high flow rates (20-50 L/min) and an initial O₃ concentration of 1-2 ppm. It has been shown that mixed Ce-Mn oxide catalysts are more active in comparison with catalysts based on individual Ce and Mn oxides. The activity passes through a maximum at the mass ratio of CeO₂:MnO₂ = 5:5, which is due to the highly dispersed state of the deposited oxides.

The work is devoted to the study of platinum-containing glass fiber catalysts (GFC) for the deep oxidation of hydrocarbons, which can be used in processes for purifying exhaust gases from volatile organic impurities, as well as for environmentally friendly combustion of fuels. The influence of the catalyst synthesis method on its activity in the deep oxidation of toluene was studied. The highest specific activity per unit mass of Pt is demonstrated by the traditional GFC IK-12-S102 based on a pre-leached zirconium-containing carrier, however, in terms of total activity per unit volume of the cartridge and per unit mass of the catalyst, GFC IK-12-S111, produced by the method of surface thermal synthesis, is more effective . The slightly higher platinum content in it is compensated by the possibility of using a significantly lighter, cheaper and more accessible carrier. It has been shown that applying a precursor solution to a carrier by spraying instead of impregnation provides an increase in specific activity. In addition, the influence of such properties as the structure of the glass fiber support (satin and openwork weaving) and the geometry of the location of the catalyst layers relative to the flow of the reaction mixture on the observed activity of the GFC was studied. It has been shown that the most effective for deep oxidation processes is the use of satin weaving as a carrier of the GFC, with the catalyst layers being longitudinally oriented relative to the flow of the reaction mixture. Criterion equations are proposed for assessing the hydraulic resistance of various types of GFC packages.

The main principles and routes of liquid-phase hydrogenation and isomerization of carbocyclic alkenes and dienes of the norbornene series in the presence of heterogeneous catalysts are systematized, and their mechanisms are considered. The reaction products were identified and the material balance was studied. Conditions for the hydrogenation and isomerization of compounds were selected, the main purpose of which was to preserve the norbornane framework. The reactivity of multiple bonds in norbornenes was assessed using experimental and quantum chemical methods. Based on the Langmuir–Hinshelwood approach and the representation of multiple adsorption of substrates on one active site, adequate kinetic models of the processes have been developed.

The influence of the ratio of active components (Fe and Cr) on the catalytic activity of FeCr/C catalysts in the oxidative dehydrogenation of ethane with CO2 was analyzed. The best results were achieved on the 2Fe3.7Cr/C catalyst, in which the Fe:Cr ratio corresponds to the stoichiometry of iron (II) chromite – FeCr2O4. The physicochemical characteristics of the prepared catalysts were obtained and analyzed (XRF, XPS, magnetometric method). From the totality of the data obtained, we can assume the presence of an iron (II) chromite phase.

This works presents a kinetic model for trimerization of ethylene to hexene-1 on a chromium-pyrrole catalyst. Within the framework of the kinetic model, a scheme of elementary reactions is suggested for description of the reactions principles. The rate constants of the process stages, components orders of reactions and activation energies reflecting the temperature dependence of reaction stages have been determined. The model results are in good agreement with experimental data in the range of pressures 18-30 bar, temperatures 105-120℃ and catalyst concentrations 1,165-3,500 mg/l.

A mathematical model that adequately describes the catalytic reforming process, the main industrial technology for producing high-octane components of motor fuels in Russia and abroad, is presented. The necessity to expand the existing transformations of gasoline-range hydrocarbons to develop a model for reforming various raw materials (gasoline fractions of thermodestructive processes, hydrocracking naphtha, gas condensate) is shown. Based on the results of the experimental studies by gas chromatography, as well as the calculations of thermodynamic parameters, an improved formalized reaction scheme different in reactions involving unsaturated hydrocarbon has been compiled. A kinetic model of the reforming process of the expanded gasoline fraction has been designed. To describe the kinetic model based on the formalized scheme of hydrocarbon transformations, the matrix method was used to make the model more flexible to the raw material composition.

The work is devoted to mathematical modeling of the process of N2O synthesis by NH3 oxidation on an Mn/Bi/Al oxide catalyst in a slot-type microstructured reactor (MSR). The characteristics of the process were studied at various linear flow rates, inlet ammonia concentrations, and reactor edge temperatures. The parameters have been determined to ensure efficient implementation of the process in the MSR under thermally acceptable conditions. The fundamental possibility of scaling an MSR by increasing its geometric dimensions by a factor of without overheating the reaction zone has been demonstrated. The results obtained indicate that in an MSR of this configuration, the N2O capacity can be increased by approximately 12 times compared to the best performance of a standard microreactor, and the specific catalyst productivity is approximately 1.5 times greater than in a traditional tubular reactor. The opportunity opens up to create small-scale production of high-purity nitrous oxide for various applications by scaling up microreactor systems. The results of the study are in line with the concept of “distributed chemicalization” and help overcome the barrier between laboratory catalytic microreactors and industrial-level devices.