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Structural modification of alumina was carried out by the decomposition of the products of the reaction of aluminum hydroxide with the organic acid used simultaneously as a peptizer and a “burnable” additive. The modification changes the acidity of the support surface and induces the formation of pentacoordinate Al3+ cations interacting with platinum, which increases the fraction of platinum atoms with electron deficiency. The alumina-platinum catalyst based on the support treated with oxalic acid shows an enhanced selectivity to aromatization in n-heptane reforming.

The influence of the alkali treatment of ZSM-5 zeolites with a silica ratio of 30 within the NaOH : SiO2 molar ratio of 0 : 230, as well as the modification of a ZSM-5 zeolite with phosphorus in the range of 0–8 wt %, on the physicochemical properties and activity in hydrogen transfer reactions in the case of conversion of aliphatic alcohols has been studied. The alkali treatment of the zeolite leads to a decrease in the zeolite silica ratio and a growth in the hydrogen transfer coefficient in the case of transformation of aliphatic alcohols. The modification of the zeolite with phosphorus is equivalent to an increase in the zeolite silica ratio, which leads to a decrease in the hydrogen transfer coefficient.

The staged crystallization of aluminophosphate AlPO4-11 from a commercially available aluminum source based on boehmite is studied for the first time by means of X-ray diffraction, 27Al and 31P magic-angle spinning nuclear magnetic resonance, low-temperature nitrogen adsorption–desorption, and scanning election microscopy. It is shown that the synthesis of AlPO4-11 proceeds via the formation of an intermediate phase based on crystalline aluminophosphate with a layered structure. It is found that AlPO4-11 with a high degree of crystallinity and phase purity forms in 6–24 h at 200°C. Lengthening the time of crystallization at 200°C to more than 48 h results in the transformation of AlPO4-11 into nonporous cristobalite. The results can be used to develop means for directional control of the phase purity and degree of crystallinity of commercially important silicoaluminophosphate molecular sieves SAPO-11 with desired properties. These can be used as a base for the synthesis of promising domestic catalysts for the commercial hydroisomerization of higher n-paraffins.

The effect of the temperature and exposure time of the starting aluminophosphate gels on their chemical and phase composition was studied. When the source of aluminum is its hydrated oxide (boehmite), gels with different contents of ammonium phosphate, undissolved boehmite, and amorphous aluminophosphate can be formed. The formation of a gel with dominant amorphous aluminophosphate allows selective crystallization of AlPO4-11 of high phase purity and ~100% crystallinity. The developed procedure for the preparation of highly dispersed aluminophosphate AlPO4-11 molecular sieves with these properties allows a transition to crystallization of silicoaluminophosphates SAPO-11—promising domestic catalysts for industrial hydroisomerization of n-paraffins in the production of Arctic diesel fuels and group III oils and isomerization of butenes.

The one-dimensional channel pore system and the moderately strong acid centers inherent in aluminophosphate (AlPO4-11) and silicoaluminophosphate (SAPO-11) molecular sieves make them promising catalyst for hydroisomerization of higher n-paraffins. However, the mechanism of crystallization of these materials is not well understood as yet. XRD,27Al and31P MAS NMR, lowtemperature adsorption-desorption of nitrogen, and SEM techniques were used for the first time for studying the stage crystallization of aluminophosphate AlPO4-11 for commercial boehmite based aluminium source. AlPO4-11 was shown to form via an intermediate phase based on layered crystalline aluminophosphate. It was established that highly crystalline and phase-pure AlPO4-11 was formed at 200 °C during 6 to 24 hours. When the crystallization at 200 °C lasted for more than two days, AlPO4-11 turned into non-porous cristobalite. The results obtained will be used for developing methods for deliberate control of the phase composition and crystallinity of industrially important silicoaluminophosphate sieves SAPO-11 with required properties to develop promising catalysts based thereon for large-scale processes of hydroisomerization of n-paraffins.

Mechanically activated dehydrochlorination of polyvinyl chloride in the presence of lithium, potassium, and calcium hydroxides was studied. Short joint mechanical treatment of polyvinyl chloride with the above bases in a high-energy centrifugal planetary mill for 5–10 min ensures the formation of polymers with a conjugated double bond system (polyvinylenes). Their subsequent heat treatment at temperatures of up to 400°С yields amorphous carbon structures. Activation of the resulting material in a CO2 medium at 850°С results in the formation of a micro-, mesoporous carbon material with the prevalent mesopore volume. The results obtained can serve as a basis for the development of technologically acceptable procedures for polyvinyl chloride waste processing to obtain demanded carbon materials without dioxin formation.

Tungstate-containing aluminum oxide is suitable as a catalyst support for hydrodeoxygenation of sunflower oil, ensuring 81–83 wt % yield of liquid products at 380°С, 4.0 MPa, and feed space velocity of 1 h–1. The catalyst acidity increases with increasing tungsten oxide content, leading to an increase in the content of decarboxylation/decarbonylation products and isoparaffins in the product mixture.

The textural and structural properties of mixed oxides Ga2O3–Al2O3, obtained via impregnating γ-Al2O3 with a solution of Ga(NO3)3 and subsequent heat treatment, are studied. According to the results from X-ray powder diffraction, gallium ions are incorporated into the structure of aluminum oxide to form a solid solution of spinel-type γ-Ga2O3–Al2O3 up to a Ga2O3 content of 50 wt % of the total weight of the sample, accompanied by a reduction in the specific surface area, volume, and average pore diameter. It is concluded that when the Ga2O3 content exceeds 50 wt %, the β-Ga2O3 phase is observed along with γ-Ga2O3–Al2O3 solid solution. 71Ga and 27Al NMR spectroscopy shows that gallium replaces aluminum atoms from the tetrahedral position to the octahedral coordination in the structure of γ-Ga2O3–Al2O3.

The structure, texture, and acid properties of platinum catalysts on oxide (Al2O3, ZrO2, ZrO2–Al2O3) and borate-containing supports (B2O3–Al2O3, B2O3–ZrO2) are studied. The catalysts are tested in the process of hydrocracking sunflower-seed oil at 380°C, 4.0 MPa, and a weight stock feed rate of 1.0 h–1. It has been found that aluminum oxide (A) contains the γ-Al2O3 phase, zirconium dioxide (Z) includes 85 and 15 rel. % of the monoclinic (M) and tetragonal (T) phases, respectively, while zirconium dioxide with the addition of 2.5 wt % Al2O3 (ZA) comprises 14 and 86 rel. % of the M–ZrO2 and T–ZrO2 phases, respectively. The B2O3–Al2O3 (BA) and B2O3–ZrO2 (BZ) systems modified with boron oxide (20 wt %) are X-ray amorphous. A Pt/BA catalyst differs from a Pt/A catalyst, while a Pt/BZ catalyst has a larger specific surface area and acidity than Pt/Z and Pt/ZA catalysts and contains Bronsted acidic centers (BACs) along with Lewis acidic centers (LACs). Only LACs are present on the surface of Pt/A, Pt/Z, and Pt/ZA catalysts. The LAC/BAC ratio in Pt/BA and Pt/BZ catalysts is 0.3 and 1.0, respectively. All the catalysts provide complete oil conversion to give C5+ hydrocarbons with a yield of 81.7–87.3 wt %. Pt/A catalyzes mainly decarboxylation and hydrogenation–dehydration reactions, while Pt/Z and Pt/ZA provide decarboxylation. The yield of diesel fraction reaches 71.8–73.9 wt % with an n-alkane content of 94.0–95.9 wt %. One-stage oil hydrocracking with the prevalence of hydrodecarbonylation and hydrogenation–dehydration reactions occurs on Pt/BA and Pt/BZ catalysts for 20 h to give the yield of the diesel fraction of at least 81.4 and 74.4 wt % and the total content of iso-alkanes and cycloalkanes of at least 28.3 and 60.7 wt %, respectively.

A method of lactic-acid (LA) polycondensation on a carbon sorbent, including sorbent impregnation and multistep thermal treatment with no catalysts or toxic solvents, is developed. This modification technique makes it possible to obtain materials with adjustable properties (molecular weight of the synthesized oligomer, amount of applied modifier, degree of screening of carbon-sorbent pores, etc.). The resulting sorbent samples were investigated using various physicochemical methods: 13С and 1Н NMR spectroscopy, low-temperature nitrogen adsorption, differential thermal analysis, etc. It is established that the modifier concentration has an impact on the physicochemical characteristics of the studied carbon-sorbent samples. Of greatest interest is the carbon-sorbent sample impregnated with a 50% lactic-acid solution with subsequent thermal treatment. Its composition includes a high content of the modifier (biologically active substance with biospecific properties) and exhibits durable action.

New copolymers containing reactive vinyltriazole units and polyvinylene blocks with conjugation system promising as materials with special electrical, physical, catalytic, and sorption properties have been prepared by the reaction of poly(vinyl chloride) with sodium salts of 1,2,4-triazole and 1,2,3-benzotriazole in a dimethylformamide medium.

The effect of temperature (530–590°C), weight hourly space velocity (2.5–7.0 h–1), and the Si/Al ratio of the ZSM-5 zeolite (30, 55, 80, 300) on the cracking of a butane–butylene fraction containing 85 wt % butylenes has been studied. The HZSM-5 zeolite has been modified with phosphorus. The effect of modification on the catalyst activity in cracking reactions has been studied. The ethylene and propylene yield achieves 38.4 wt % at a degree of conversion of butylenes of 81.5%. The ethylene to propylene ratio is 0.55.

A method for carbon materials synthesis based on polyvinyl chloride has been proposed. Method includes polymer dehydrochlorination by alkali with carbon-rich conjugated structures (polyvinylenes) formation and its subsequent carbonization at relatively low temperatures. Raman and 13C NMR spectroscopy and transmission electron microscopy show that thermal treatment of the resulting polyvinylenes up to 400 °C leads to the formation of amorphous carbon material with chlorine contain less than 0.5 wt.%. These results can be used to develop dioxin-free technology of utilization of polyvinyl chloride and its wastes.

Methane adsorption on the Pt–H/Al2O3 and Pt/Al2O3 catalysts begins at Т = 475°C and is accompanied by the appearance of hydrogen in the reaction medium. At a higher temperature is raised to 550°C, the amount of adsorbed hydrogen increases to 1.1 and 0.8 mol/(mol Pt), respectively. According to the calculated degree of methane dehydrogenation on platinum sites at Т = 550°C, the Н/C ratio is 1.3 (at/at) for the Pt–H/Al2O3 catalyst and 1.5 (at/at) for the Pt/Al2O3 catalyst. The introduction of n-pentane into the reaction medium increases the yield of aromatic hydrocarbons (benzene and toluene) by a factor of 8.8 over the arene yield observed in individual n-pentane conversion. A mass spectrometric analysis of the arenes obtained with the Pt/Al2O3 catalyst has demonstrated that 37.5% of the adsorbed methane is involved in the methane–n-pentane coaromatization yielding benzene and toluene.

The compositions of aqueous 2-aminoethanol solutions used in industry for absorption of carbon dioxide resulting from combustion of natural gas have been determined by 1H and 13C NMR spectroscopy. The absorption process does not involve generally accepted paths of thermal decomposition of the absorbent in the reaction with carbon dioxide, but the main path is non-oxidative decomposition of 2-aminoethanol into ammonia and ethylene oxide. Splitting of the NMR signals of carbamate anion formed by reaction of 2-aminoethanol with carbon dioxide has been rationalized by specific structure of the anion due to intramolecular hydrogen bonding.

For the first time it was established that the catalytic hydrogenation of 2,4,6-trinitrobenzoic acid to 1,3,5-triaminobenzene can proceed via the formation of aromatic hydroxyamines and cyclohexane-1,3,5-trione trioxime. As a result of aqueous-phase hydrogenation of sodium salt of 2,4,6-trinitrobenzoic acid in the presence of 5%Pd/Sibunit catalyst at a temperature of 323 K and pressure of 0.5 MPa, a trioxime in high yield (about 70 %) was obtained. Due to high selectivity to cyclohexane-1,3,5-trione trioxime the catalytic hydrogenation of sodium salt of 2,4,6-trinitrobenzoic acid can be considered as a new method for its synthesis.

For changing the texture of the mesoporous carbon composite Sibunit, its modification by treatment with furfuryl alcohol and the solutions of furfuryl alcohol in water and benzene followed by the carbonization of a polymer was studied. It was found that the composition of a modifying liquid phase has an effect on the textural characteristics of Sibunit, and the most essential pore-size redistribution occurred with the use of the aqueous solutions of furfuryl alcohol. The conditions under which the micropore structure of the modified Sibunit was maximally developed were determined.

The surface of the VNIITU-1 carbon mesoporous sorbent was modified with poly-N-vinylpyrrolidone characterized by antibacterial activity. Synthesis was carried out in two stages: (1) impregnation of the carbon sorbent by an aqueous solution of poly-N-vinylpyrrolidone with the molecular mass of 10000 g/mol; and (2) impregnation of the carbon sorbent by an aqueous solution of the (N-vinylpyrrolidone) monomer and initiator with their further polymerization in an inert atmosphere. Carbon sorbent samples were studied using a complex of physicochemical methods: scanning electron microscopy, infrared spectroscopy, low-temperature nitrogen adsorption, nuclear magnetic resonance, and thermogravimetry. It was found that the polymer obtained on the carbon surface is free of the initial toxic VP monomer. Microbiological tests of modified sorbents with respect to pathogenic and opportunistic microflora were carried out.

The surface of a VNIITU-1 carbon mesoporous hemosorbent is modified with poly-N-vinylpyrrolidone, which possesses its own antibacterial activity. The modification is performed in two steps: (1) impregnation of the monomer, N-vinylpyrrolidone, and the initiator in an aqueous solution and (2) polymerization in an inert atmosphere. The composition of products produced during polymerization reaction is analyzed by NMR 13C. The texture characteristics, the relief and the morphology, and the content of nitrogen in the initial and modified sorbents are studied by current physicochemical methods. Bench tests show that the contact with the modified sorbent leads to a decrease in the amount of Staphylococcus aureus bacterial cells and inhibition of their growth in comparison with the initial carbon sorbent.

On mixing acetone solutions of 4,5-dichloro-2-dichloromethylen-4-cyclopenten-1,3-dione with thiourea or its homologs clear yellow amorphous hygroscopic precipitates were formed practically quantitatively and instantaneously, which are probably the predicted half a century ago Mobius aromatic compounds.

Earlier reported schemes of main way of absorbent degradation were corrected un the course of joint studies by NMR and chromatography-mass spectrometry of a composition of aqueous solutions of monoethanolamines used in absorption removing acidic impurities H2S, CO2, SO2, COS, CS2 from exhaust gas and in view of new literature data.

The arguments in favor of a change in the accents at the description of the reaction mechanism of the isobutene alkylation with butylenes in the presence of sulfuric acid are proposed. The reaction of sulfate sulfur reduction that until now considered as the side process is proposed to suggest as just the initiation of chain process which includes generation of tert-butyl cations. Such a concept makes it possible to explain a number of characteristic experimental data, in particular failure of attempts of creation of the effective solid catalyst for the alkylation on the basis of the sulfated zirconium oxides.

Nitration of 1,3,3-trimethyl-1-phenylindane (phenylindane) by nitric acid of different concentration over mesoporous aluminosilicates with the molar ratios SiO2 : Al2O3 = 20, 40, and 80 was studied. The effects of the SiO2 : Al2O3 and phenylindane : nitric acid ratios, the concentration of nitric acid, and temperature on the conversion of phenylindane and the yield of dinitrophenylindane were revealed. The aluminosilicate samples with a SiO2 : Al2O3 ratio of 20 are shown to have the highest activity. In the presence of these samples, the conversion of phenylindane reaches 100% with a selectivity of formation of 5and 6-nitro-1-(4´-nitrophenyl)1,3,3-trimethylindanes close to 80% (70% nitric acid, 100 °C).

Composition of a series of formulations used in Russia for production of various perfumes, among them car air fresheners, was studied by 13C and 1H NMR. The main components were identified, approximate compositions of several perfumes were determined, and spectral data are given. These spectral data can be used for prompt analysis for composition of commercial odorants with the aim of monitoring their quality and hygienic characteristics.

The composition of aqueous solution of monoethanolamine used in various units of gas treatment of the Omsk Oil-Refining Plant, Joint-Stock Company, was studied by the 13C NMR spectroscopy. The components of the gases to be purified and the reactions producing the impurities were established.

The main impurities in aqueous solution of monoethanolamine used in various stages of gas treatment at the Omsk Oil Refinery Joint-Stock Company were identified by 1H and 13C NMR spectroscopy. A mechanism of their formation was proposed. A probable dependence of service characteristics of the absorbent on its composition was considered.

A procedure for fast determination of the total content of arenes in reformer naphthas by 1H NMR spectroscopy was developed and tested. Their content is determined from the ratio of the integral intensities of the signals of aromatic protons and alkane methyl protons, using a calibration plot constructed on the basis of GLC data.