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Two- and three-component systems of deep eutectic solvents (DES) based on polyatomic alcohol - pentaerythritol (PER), carbonic acid diamide - urea (carbamide, CA) and quaternary ammonium salt - choline chloride (CC) were synthesised: PER-CC, PER-CA, CC-CA, PER-CA-CC. Eutectic points in the obtained DES systems were determined. It is shown that the lowest melting point (-14.5 °C) is observed for the three-component DES system based on PER-CA-CC with the molar component ratio of 1.3 : 2.4 : 1, respectively. The solubility of this three-component system was determined by dissolution in water prior to precipitation. The density of the aqueous solutions of binary DES systems was determined to be within the range of 1.2158-1.2458 g/cm³. The presence of hydrogen bonds in binary and ternary DES systems was revealed by IR spectroscopy: CC acts as an acceptor of hydrogen bonds, while PER and CA act as donors. The presence of hydrogen bonds between DES components provides the formation of stable molecular complexes and lowering of the melting/crystallisation points of DES compositions due to intermolecular bond weakening and destruction of the crystal structures of initial substances.

Extrusion-based 3D printing methods are widely used to fabricate tissue-engineered constructs for regenerative medicine with specific dimensions, shapes, and properties tailored to the nature of the wound defect. High-viscosity solutions of the anionic polysaccharide sodium alginate show a potential as a base material for developing hydrogel inks for 3D printing. However, printing with sodium alginate solutions presents technical challenges due to the need for rapid gelation immediately after extrusion to form an elastic gel. This study demonstrates the possibility of controlling the viscosity of sodium alginate solutions by introducing a gelation modifier - ferulic acid, which participates in the formation of an entanglement network. Using IR spectroscopy, the nature of interactions in alginate-based materials obtained in the presence of ferulic acid was investigated. The conditions for producing highly hydrated gel structures based on an ionogenic polysaccharide solution and ferulic acid were optimised using piston-based 3D printing.

This article is concerned with the urgent problem of atmospheric air pollution in the post-industrial phase of the development of mining regions. Methodological approaches to the hygienic diagnostics of local aerosol pollution of the atmosphere have been elaborated. The modeling object was the Ursk dump of barite-pyrite loose material, formed in the 1930s after gold extraction by cyanidation in Ursk settlement, the Kemerovo Region. The field model of the dump was formed by the samples of sulphide-containing wastes collected from the object in summer. At the first stage, a theoretical analysis of the information presented in the literature on the physicochemical and toxic properties of aerosol particles in the submicron range, which pose risks to the environment and public health in mining areas, was carried out. At the stage of hazard identification, the application of the field modeling of atmospheric migration processes of target particles and mercury vapour from a sulphide-containing waste disposal facility was scientifically justified. At the modelling stage, which consisted of heating the waste samples to a temperature of 27.1±0.04, 33±0.1 and 50±0.3 °C, the trends of air concentrations of aerosol particles of various ranges and their correlations were estimated. At the design stage, the probability of accumulation of submicron particles and mercury vapour in the air basin, which poses a significant danger to the environment and public health, was determined. The data obtained from the results of simulation are intended for information provision of planning and implementation of measures for land reclamation and environmental improvement.

The effect of indium oxide additive on the properties of Pd-containing catalytic systems Pd/WO₃-ZrO₂ based on zirconia modified with tungstate anions (tungstated zirconia catalysts) and Pd/WO3-ZrO₂/Al₂O₃ catalysts in which the active component WO₃-ZrO₂ providing the acid properties of catalysts is introduced into the porous matrix of the alumina support is investigated. It is shown that the introduction of indium oxide additive in an amount of 0.5-1.5 wt% into the catalyst composition enhances their activity and also increases the yield of the target reaction products - octane isomers. The introduction of 0.5 wt% indium oxide into the composition of tungstated zirconia catalysts supported on alumina leads to an increase in octane conversion by 5.8 % and a rise in the yield of the target reaction products - octane isomers by 4.7 wt%. For Pd/WO₃-ZrO₂ catalysts, the introduction of indium oxide additive in an amount of 1.0-1.5 wt% leads to an increase in octane conversion by 28.0-38.7 %, with a rise in the yield of isomers by 17.0-21.3 wt%. The positive modifying effect of indium oxide additive to the Pd/WO₃-ZrO₂ catalysts is due to an increase in the proportion of the active tetragonal phase of zirconia from 33 to 43-63 %, a rise in the specific surface area from 28 to 38-40 m²/g and an increase in total acidity according to temperature-programmed desorption of ammonia from 113 to 122 μmol/g. The introduction of the active component into the porous alumina support causes an increase in the proportion of weak acid sites of the catalysts, which provides an increase in selectivity to octane isomers. The addition of indium oxide allows regulating the phase composition, textural characteristics and acid properties of palladium-containing tungstated zirconium catalysts, which determines their catalystic activity, and allows obtaining active and selective catalysts of octane isomerization - Pd/In₂O₃-WO₃-ZrO₂ and Pd/In₂O₃-WO₃-ZrO₂/Al₂O₃.

2025 was an anniversary year for the Federal Research Center of Coal and Coal Chemistry of the Siberian Branch of the Russian Academy of Sciences (FRC CCC SB RAS, Kemerovo), and in 2024, the Institute of Coal Chemistry and Material Science (ICCMS), which is now part of FRC CCC SB RAS, celebrated its 50th anniversary. The chronology of the ICCMS formation is presented below. From October 7 to 9, 2025, the city of Kemerovo hosted the 14th International Russian-Kazakhstani Symposium “Carbon Chemistry and Ecology of Kuzbass”, dedicated to the 10th anniversary of FRC CCC SB RAS. This issue of the journal “Chemistry for Sustainable Development” presents materials on the best presentations of the symposium participants.

The study presents a comparative investigation of the yield of gaseous products released during the pyrolysis of a tableted sample of lignite microparticles under the influence of pulsed-periodic laser radiation (6 Hz, 1064 nm, 0.2-2 J/cm²) with nanosecond (12 ns) and microsecond (120 μs) pulse durations. The laser pyrolysis of the coal samples was conducted in an argon atmosphere, with the gaseous products analysed using mass spectrometry. The gaseous pyrolysis products under microsecond pulses contained H₂, CH₄, H₂O, CO, and CO₂, while under nanosecond pulses, H₂, CH₄, C₂H₂, CO, and CO₂ were detected. The yield of gaseous products and the proportion of combustible gases per unit laser pulse energy density were higher for nanosecond laser irradiation. The mass of ablation products from the tableted coal microparticle sample under nanosecond pulses of the same energy density was greater than under microsecond pulses. The observed results are attributed to optical breakdown induced by high-intensity nanosecond pulses, leading to the increased formation of gaseous products and the generation of a stronger shock wave, causing ejection of particles from the tableted sample volume and rapid sample destruction.

A detailed study of high-temperature solid-phase transformations occurring in dispersed microspheres smaller than 10 mm in size (d_m = 3 mm and d₉₉ = 10 mm) belonging to the suspended matter (PM₁₀) of fly ash from the combustion of hard coal from the Ekibastuz and Kuznetsk coal basins has been carried out within the synthesis of glass-ceramic materials. It has been established for PM₁₀ microspheres of macrocomponent composition SiO₂-Al₂O₃-FeO isolated as narrow fractions from fly ash from the combustion of Ekibastuz coal that there is an increase in the content of mullite phase (from 17 to 31 wt%), cristobalite phase is formed (up to 29 wt%); the content of glass phase decreases from 65 to 25 wt%. In the samples of narrow fractions of PM10 microspheres from fly ashes from Kuznetsk coal combustion, crystallisation of the glass phase at 1100 °C leads to a noticeable increase in the concentration of mullite phase (from 3 to 17 wt%), the formation of cristobalite and anorthite phases (3 and 6 wt%, respectively); the amount of glass phase decreases from 93 to 70 wt%. A well-consolidated composite with low porosity (0.4 %), insignificant water absorption (0.2 %), and high strength (56 MPa) was obtained using the direct sintering method based on dispersed microspheres of PM₁₀ fly ash from the combustion of Kuznetsk coal. On the basis of dispersed microspheres of PM₁₀ fly ash from the combustion of Ekibastuz coal, high-porous (open porosity 44-52 %) composites with the homogeneous microporous structure, strength 20-36 MPa, liquid permeability up to 478 L/(m2⋅h⋅bar) and the dispersed microimpurities retention ratio of 0.98-0.99 were obtained. The acid resistance of the obtained glass-ceramic materials is 97-100 %.

The results of laboratory coking are presented for GZh, Zh rank coal (two concentrates from different manufacturers), KZh + Zh, OS rank coal (two concentrates from different manufacturers) in the experimental furnace with 4 kg load, and the studies of resulting coke. The structural strength (S_s) of coke samples was determined according to GOST 9521-2017. Samples were studied by X-ray diffraction analysis, and the sizes of molecularly oriented domains in the coke were determined: domain height (L_c), domain length (L_a), interplanar distance (d₀₀₂), and the number of lamellas (N) in the domain package. The relationship between the structural strength of coke and the chemical-petrographic parameters of coal was studied (the yield of volatile substances per dry state, vitrinite reflectance index, the sum of lean components, the thickness of plastic layer). It has been determined that the structural strength of coke has a quadratic dependence with respect to the chemical-petrographic parameters of coal. According to the experimental results, it is demonstrated that for coke obtained from the OS rank coal, the 0.4 nm difference in L_c and 0.3 nm difference in L_a correspond to a 50 % change in the structural strength of coke. For coke obtained from the Zh rank coal, the 0.28 nm difference in L_c and 0.46 nm in L_a corresponds to a 23 % change in the structural strength of coke. It is concluded that the L_c and L_a indicators make it possible to differentiate the quality of coke by structural strength, unlike for the chemical-petrographic indicators of coal. The general trend of changes in the L_c and L_a domain sizes depending on the structural strength of coke and the stage of coal metamorphism in the sequence GZh, Zh, KZh + Zh, OS is given.

The sorption of sodium, silver, magnesium, calcium, copper, lead and iron cations on the sulphocationite obtained by sulphonation of non-coking long-flame coal of the early stage of metamorphism from the Zadubrovsky open-cast coal mine in the Kemerovo Region was studied. The work primarily focuses on the selective sorption of heavy metal cations (Pb²⁺, Mn²⁺, Ni²⁺, Fe³⁺), which pose a special danger to water resources and human life. The sulphocationite under investigation was obtained by treating the coal with concentrated sulphuric acid and oleum. The dynamic ion exchange capacity of the sulphocationite by strongly acidic groups is 1.4 mg-eq per 1 g of the H-form of dry sulphonic coal (0.7 g-eq/dm³). The equilibrium of cation exchange of protons in SO₃H groups of sulphocationite with Na⁺, Ag⁺, Ca²⁺, Cu²⁺, Mg²⁺, Pb²⁺, Fe³⁺ cations from aqueous solutions at 298 K was studied using the dynamic method. It has been shown that the logarithms of the corrected selectivity coefficients of binary cation exchanges Cat/Н (Cat = Na⁺, Ag⁺, Mg²⁺, Ca²⁺, Cu²⁺, Pb²⁺, Mn²⁺, Ni²⁺, Fe³⁺) depend linearly on the equivalent fraction of cations in the sulphocationite based on long-flame coal. The slopes of the straight lines are associated with the energy inequality of the exchange sites, which make an additive contribution to the Gibbs energy of the system when the counterionic composition of the sulphocationite changes. The studied sulphocationite has unique properties: high capacity and selectivity of metal cation sorption from aqueous solutions. The sorption selectivity of heavy metal cations and the factors of metal/proton separation between the solution and sulphocationite phases increase sharply as the concentration of cations in water decreases. The revealed trend increases in the sequence of heavy metal cations Mn²⁺ < Ni²⁺ < Cu²⁺ < Fe³⁺ < Pb²⁺. The results obtained in the work are promising for the advance in the methodology of deep demineralisation of water using the ion-exchange sorption of metal cations by the sulphocationite based on long-flame coal.

The Pd/N-C catalysts based on the carbon support Sibunite modified by the introduction of nitrogen by the treatment in NO under static reactor conditions were developed. It has been established that at a temperature up to 120 oC the conversion of formic acid is higher over the system Pd/N-C in comparison with the unmodified Pd/C catalyst. X-Ray photoelectron spectroscopy was used to identify the states of nitrogen and palladium in the resulting systems. Transmission electron microscopy was used to study the particle formation trends in the Pd/C and Pd/N-C catalysts, as well as their thermal stability.