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The applicability of a porous carbon material obtained as a result of the “chemical” dehydrochlorination of chlorinated polyvinyl chloride as a support for palladium hydrogenation catalysts was demonstrated. The efficiency of the catalyst was evaluated in the liquid-phase reactions of nitrobenzene hydrogenation and chlorobenzene hydrodechlorination. Although the specific activity of the catalyst was lower by a factor of 3–4 than that of the samples based on Sibunit and carbon nanotubes, the complete conversion of the initial compounds with the selective formation of end products under mild conditions was achieved at a relatively low palladium content (1.5%).

The effect of a nanosecond high-power ion beam on thin polymer layers of chlorinated polyvinyl chloride and polymethyl methacrylate containing ferrocene as an additive is investigated. Arrays of carbon nanofibers with a characteristic diameter of 30–160 nm and lengths of up to 15 m are formed on the surface of the chlorinated polyvinyl chloride. The same effect on polymethyl-methacrylate layers leads to intense cavitation of the surface layer. The possible mechanisms of the formation of carbon nanofibers in chlorinated polyvinyl chloride with ferrocene additive under the action of a high power ion beam are discussed.

Mechanochemical activation of PVC in a high-energy centrifugal-planetary mill was shown to increase its reactivity in dehydrochlorination under the action of bases. Thus modified PVC is capable of low-temperature carbonization and can form a carbon material even at the temperatures below 400°C.

The liquid-phase hydrogenation of aromatic trinitro compounds was studied at atmospheric and elevated pressure and a temperature of 50–70 °C. It was shown that at atmospheric pressure, irrespective of the solvent type (water or acetic anhydride), a complete reduction of the nitro groups of 2,4,6-trinitrobenzoic acid to amino groups does not occur; the intermediate products of hydrogenation and the products of secondary transformations are present in the solution. An increase in pressure to 5 bars ensures a complete hydrogenation of 2,4,6-trinitrobenzoic acid and 1,3,5-trinitrobenzene with the formation of 1,3,5-triaminobenzene.

Chlorine-substituted polymers with a system of conjugated double bonds—polyvinylene chlorides, which were prepared by the chemical dehydrochlorination of carbon-chain chloropolymers with a Cl content of higher than 60 wt %, being polymeric electron acceptors, were found to form complexes with alkali metal hydroxides (LiOH, NaOH, and KOH). The resulting complexes exhibit high sorption capacity for phenol. The static exchange capacity of the alkaline complexes of polyvinylene chlorides for phenol is as high as 310 mg/g in an aqueous medium or 90 mg/g in an atmosphere of air; these values are comparable with the sorption capacity of the known sorbents of phenol.

A high-energy planetary mill AGO-2 was used for mechanical activation of synthetic graphite with the particle size of 25–30 μm and specific surface area S BET = 3.0 m 2 /g in air for 1–60 min at a 100 g acceleration of milling bodies. The X-ray diffraction, Raman spectroscopy and electron microscopy studies showed that the 60 min mechanical activation of graphite decreases the number of graphene layers in graphite crystallites to 8–12 and induces their turbostratic disorder. The size of graphite particles decreases to 6.9 μm after 30 min of mechanical activation and increases to 12.1 μm when the time of mechanical activation is extended to 60 min. Similar changes are observed for the true density of graphite: after 60 min of mechanical activation it becomes equal to 2.48 ⋅ 10 3 kg/m 3 , which is by 10% higher than the true density of graphite not subjected to such treatment. The specific adsorption surface of graphite ( S BET ) reaches its maximum values, 427–460 m 2 /g, after 7–12 min of mechanical activation. A further increase in the activation time to 30–60 min decreases S BET of graphite to 230–250 m 2 /g. Due to attrition of steel milling bodies caused by mechanical activation, iron is accumulated in the samples and its content exceeds 5%. Iron is distributed uniformly in the graphite as the 30–100 and 3–5 nm particles of hematite and iron carbide. The IR spectroscopy study revealed the formation of 0.8 mEq/g of the hydroxyl, phenolic, lactone and carbonyl groups on the graphite surface in the course of mechanical activation.

The properties of Pt/MgAlO x catalysts based on aluminum–magnesium layered hydroxides have been investigated in n-decane dehydrogenation. The n-decene formation selectivity depends on the Mg/Al ratio in the support, on the platinum complex binding conditions, and on the platinum content of the catalyst. Increasing the proportion of magnesium decreases the number of acid cites in the support and changes the properties of supported platinum. As a result, the n-decene formation selectivity under the appropriate conditions reaches 90% without a modifier added.

Studies of the structural transformations of carbon black caused by laser and electron irradiation have been carried out using high-resolution transmission electron microscopy (HRTEM). The heterosystems of the Pt/C-type are obtained in the process of laser irradiation of carbon black suspensions in platinum-containing solutions. A high-energy electron irradiation of carbon black causes the formation of multimorphological carbon nanostructures, which possess a graphite-like arrangement of graphene layers.

The surface of the VNIITU-1 carbon mesoporous sorbent was modified with polyglicolic acid characterized by antibacterial and antifungal properties. Synthesis was carried out in three stages: 1) carbon sorbent impregnation with 50% aqueous glycolic acid solution for 8 h, 2) sorbent drying for 1 h at a temperature of 105 ± 2°C; 3) and thermal treatment of the carbon sorbent impregnated by glycolic acid during the first hour at a temperature of 195 ± 5°C with further heating for 5 h at the temperature of 225 ± 5°C. Carbon sorbent samples were studied using a complex of physico-chemical methods: scanning electron microscopy; IR spectroscopy; X-ray photoelectron spectroscopy; low-temperature adsorption of nitrogen; nuclear magnetic resonance; thermogravimetry; X-ray microanalysis; and C, H, S, O analysis. It is found that the modifier is strongly fixed in the carbon sorbent surface predominantly in the form of glycolic acid oligomers (hexamers). As a result of modification, the amount of oxygen-containing moieties increases considerably as compared to the initial sorbent. The synthesized samples are of great interest as materials for sorption medicine.

The effect of the composition of a dry mix containing molybdenum oxide, carbon, and reducing metal (Zn or Al) on the formation of molybdenum carbides during the mechanical activation (MA) of the mixture is studied. The phase composition of the mechanically activated samples is studied via X-ray phase analysis (XPA). The optimum formulation of the mixture and the MA modes ensuring a yield of highly dispersed carbide-containing catalyst with Mo2C + Al2O3 composition are determined. It is shown that the composition of the medium (air or argon) has no appreciable effect on the phase composition of the target product (molybdenum carbide). Catalytic testing of carbide-containing catalyst in the reaction of hydrodesulfurization of dibenzothiophene (DBT) is conducted, and it is established that this catalyst exhibits high activity and selectivity: at 320°C, the conversion of DBT is 92.8% and the content of cycloalkanes is 88.3%. The obtained results can be used to create an industrial zero-waste technological process for the production of molybdenum carbide.

Nanocapsules and stacks of graphene sheets have been prepared from carbon black by irradiation relativistic electron beam. Electrons with energy of 2.5 MeV were used in these experiments to produce carbon nanoparticles with graphite-like structure of the graphene layers. High Resolution Transmission Electron Microscopy (HRTEM), Raman spectroscopy and Electron Spin Resonance (ESR) spectroscopy were used to obtain the information about morphology, crystallinity, and interlayer distance of these nanostructures.

The results of studies on the preparation of Ni-Mo sulfide catalysts based on a carbon-carbon composite material of the Sibunit type for the hydrocracking of heavy petroleum residue are reported. The effects of the support texture and the conditions of catalyst preparation on catalytic activity in the model reactions of 1-methylnaphthalene and dibenzothiophene conversion were demonstrated.

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 methods of regulating the porous structure and properties of carbon materials of the Sibunit type are considered. The deposition to 10–15 wt % pyrolytic carbon in the pore space of Sibunit makes it possible to regulate pore volume and pore-size distributions by decreasing the fraction of micropores and small mesopores and to enhance the strength characteristics of the support. Heat treatment in an inert atmosphere in a temperature range of 2200–2600°C imparts a number of unique specific properties to the Sibunit supports, in particular, high resistance to oxidative and electrochemical corrosion, which is comparable with the resistance of graphite. At the same time, it retains sufficiently high pore structure characteristics and adsorption properties typical of porous carbon materials. The introduction of water-soluble organic compounds capable of producing microporous carbon upon carbonization at the stage of granulation or the supporting of organic compounds on Sibunit with the subsequent polymerization and carbonization in the support pores makes it possible to form micropores with a volume to 0.20–0.25 cm3/g in Sibunit.

A series of Pd/C catalysts (2–4 wt % Pd) with different particle sizes of the supported metal was prepared under varied conditions of the formation and surface deposition of the polynuclear hydroxo complexes (PHCs) of palladium(II) on powdered Sibunit carbon supports with their subsequent reduction to the metal. It was found that the liquid-phase hydrogenation of ethyl p-nitrobenzoate to anesthesine (benzocaine) on these catalysts is a structurally sensitive process, and the dependence of the activity of catalysts on their dispersity is expressed as an extremal function; in this case, the most effective catalysts had the average Pd particle size of 3–5 nm. It was demonstrated that the degree of catalyst utilization increased with the pH of Pd(II) PHC formation; this fact indicates that egg-shell-type catalysts were formed at high values of pH. The Pd/Sibunit catalysts are promising for use in the pharmaceutical industry for the synthesis of local anesthetics with p-nitrobenzoic acid as an intermediate.

Prospects for the application of porous granulated carbon-carbon materials synthesized based on nanodispersed carbon filling agents and a pyrolytic carbon matrix to processes in the hydrometallurgy of nonferrous metals are demonstrated. The results of the sorption of organic impurities from model and real process liquors used in the hydrometallurgy are considered using Tekhnosorb-1M carbon-carbon sorbent as an example. The results of the use of this material under industrial conditions at OOO NPF Baltiiskaya Manufaktura, one of the largest scale producers of cobalt salts in Russia, are also discussed.

While synthesizing platinum catalysts supported on aluminum-magnesium oxides (Pt/MgAlO x ), we established that, in the binding of the Pt(IV) chloro complex to aluminum-magnesium layered double hydroxides (LDHs), the mechanism of the metal complex-support interaction depends on the nature of the interlayer anion of the LDH. The synthesis may yield chemically identical Pt/MgAlO x samples differing in the particle size and electronic structure of supported platinum. The higher dehydrogenating activity of the catalyst obtained by binding the [PtCl6]2− complex in the interlayer space of LDH via exchange with interlayer OH− anions is possibly due to the larger proportion of metallic platinum (Pt0) in this catalyst. In the catalyst prepared from hydrolyzed platinum complex species using LDH with CO 3 2− interlayer anions, platinum is mainly in an oxidized state similar to Pt2+.

The latest advances in the synthesis of granulated carbon-carbon materials based on nanodispersed globular and pyrolytic carbons modified with silicon or its compounds at the Institute of Hydrocarbons Processing, Siberian Branch, Russian Academy of Sciences are considered. The methods and main regularities of the synthesis and the physicochemical properties of silicon-containing composite materials like C/SiO2, C/SiO2/C, and SiO2/C are discussed. It is shown that the synthesis of modified nanocomposites with the use of polyorganosiloxanes is a promising line in the development of silicon-containing carbon-carbon materials. In this work, a nontraditional approach to the production of mesoporous silicon dioxide based on nanodispersed globular carbon and polyorganosiloxanes is proposed.

The effect of mechanochemical activation parameters-process power density and the time of treatment of a mixture of nickel hydroxocarbonate NiCO3 · 2Ni(OH)2 · nH2O and ammonium paramolybdate (NH4)6Mo7O24 · 4H2O -on the phase composition, specific surface area, and morphology of mechanically activated products at different Ni: Mo atomic ratios was studied. It was found that, at a mechanochemical activation process power density of 6.2 W/g, layered transition metal molybdates (LTM compounds) with different amounts of crystal water were the constituents of the products, whereas the products mechanically activated at a power density of 28.0 W/g contained a mixture of LTM compounds and heteropoly compounds with the Anderson structure regardless of activation time.

The precursors of massive Ni-Mo catalysts for hydrotreating processes, which were synthesized by the mechanochemical activation of a mixture of nickel hydroxocarbonate NiCO3·2Ni(OH)2·nH2O and ammonium paramolybdate (NH4)6Mo7O24 · 4H2O, were sulfidized. Their structure was studied by X-ray diffraction analysis and high-resolution electron microscopy. It was found that MoS2 packets, which are characterized by the presence of structural defects and geometric curvature, are the constituents of the massive catalysts. The catalyst also includes a phase of Ni3S2 and regions containing a complex Ni-Mo-S phase. The catalytic tests of the synthesized catalysts in the model reactions of 1-methylnaphthalene and dibenzothiophene conversions showed that the catalyst whose precursor was a heteropoly compound with the Anderson structure after the stage of mechanochemical activation exhibited the highest activity.

Procedures for the synthesis of massive molybdenum carbide by the mechanical activation of a mixture of MoO3, commercial carbon, and Zn in air and the synthesis of the supported carbide-containing catalyst Mo2C/C by the mechanical activation of commercial carbon impregnated with a 16% aqueous solution of ammonium paramolybdate in an inert atmosphere were developed for the first time. With the use of a set of physicochemical methods, the metal contents, particle sizes, specific surface areas, and phase compositions of the mechanically activated composites were determined. The structure of the carbide-containing supported catalyst was studied by electron microscopy, and its acidic properties were studied by the temperature-programmed desorption of ammonia; catalytic tests in the model reactions of dibenzothiophene (DBT) and alkane aromatization were performed. It was found that the Mo2C/C catalyst exhibited high activity in these reactions: the conversion of DBT at a contact time of 3–6 h was 80–85%. The conversion of n-heptane at a contact time of 2 h was 31.2%, and 100% toluene was the reaction product. An increase in the contact time to 6 h led to a decrease in the conversion of n-heptane to 1.3%, and to 47% C6-C7 cycloalkanes were present in the reaction products. The results of this work are indicative of the high catalytic activity of the Mo2C/C catalyst obtained by mechanical activation.

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.

We studied methane pyrolysis of at 750 to 1100°C on a heat-treated FeCrAl wire heated by electric current both in the absence of oxygen and at CH4 : O2 = 15 : 1 and 9 : 1. The process proceeds in two temperature ranges differing in pyrolysis product selectivity. In the transition region, intensive carbon deposition occurs on the wire surface. The presence of oxygen shifts the methane conversion versus temperature and product selectivity versus temperature curves to higher temperatures. We believe that the existence of two process regions is due to the coking of the catalyst surface.

The transformations of platinum(IV) complexes subsequent to their sorption on the support are considered. As the Pt(IV)/Al2O3 systems are dried at 25°C in daylight, their dehydration is accompanied by the replacement of inner sphere ligands of Pt(IV) by OH groups and the Coulombic bonding between the adsorbed metal complexes and the support turns into coordination bonding. Drying at a higher temperature of 120°C does not increase the extent of hydrolysis of the bound complexes in the predried samples. The observed increase in the proportion of unreadily reducible platinum species is likely due to the multisite adsorption of platinum complexes taking place.

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.

The possibility of synthesizing bulk catalysts by means of mechanochemical activation (MCA), the basis for wasteless technologies for the production of catalysts with particle sizes less than 10 μm, is demonstrated. The precursors of Ni-Mo catalysts for hydrogenation processes are synthesized by MCA. The chemical and phase composition and specific surface area of mechanically activated composites with Ni: Mo atomic ratio = 1.0 and 1.4 are studied by DTA, XRD, TPR, and low-temperature adsorption. It is established that during the simultaneous MCA of Ni- and Mo-containing salts, solid-state reactions yield complex X-ray amorphous compounds that after calcination at 520°C form nickel molybdates composed almost entirely of highly active modified β-NiMoO4, the sulfidation of which produces MoS2 and Ni3S2 phases. Comparative testing of sulfide catalysts (i.e., bulk (Ni: Mo = 1.4) and industrial supported) in model reactions of the conversion of 1-methylnaphthalene and dibenzothiophene was performed at a temperature of 350°C, a pressure of 3.5 MPa, a feedstock hourly space velocity of 2 h−1, and a hydrogen/feedstock ratio of 600. Based on the composition of the 1-methylnaphthalene and dibenzothiophene conversion products while using industrial and bulk catalysts, it is concluded that the bulk catalyst exhibits higher hydrogenating activity.

Mechanochemical activation in high-energy planetary activators was used for the preparation of highly dispersed nickel-molybdenum compounds. Nickel hydroxocarbonate [NiCO3 · 2Ni(OH)2 · nH2O] and ammonium paramolybdate [(NH4)6Mo7O24 · 4H2O] were chosen as starting compounds. The effect of the Ni: Mo atomic ratio on the composition and structure of products formed in the process of mechanochemical activation followed by calcination was studied. It was found that, at the Ni: Mo atomic ratios of 1.0 and 1.4, the mechanically activated product after calcination at 520°C contained 70–100% β-NiMoO4, which is a stable phase at temperatures lower than 180°C.

The scientific and technical achievements made during the last 15 years in the deoxygenation processes for the production of hydrocarbon biofuels from oil and fatty raw materials are reviewed. The most advanced methods for the processing of triglycerides into hydrocarbons are associated with the use of pyrolysis, catalytic cracking, and hydrotreatment processes similar to those already used at petrochemical plants and oil refineries. The hydrotreatment technologies, which have already been adopted or ready for industrial application, are considered in more details. Nonsulphide catalysts for the single-stage production of waxy diesel fractions from vegetable oils and combined technologies are promising for reducing the consumption of hydrogen and increasing the yield of hydrocarbon products and the flexibility in obtaining different types of fuel.

A method is suggested for modifying the surface properties of alumina without changing its chemical composition. The sorption of aluminum complexes with organic acid ligands on the γ-Al2O3 surface is reported. The thermal decomposition of the adsorbed oxalate complexes yields supported aluminum oxide compounds on the surface of the initial support. This modifies the functional cover of the γ-Al2O3 surface, altering the proportions of different types of surface hydroxyl groups, reducing their total number, and lowering the concentration of weak Lewis acid sites.

The liquid-phase catalytic hydrogenation of acetylene into ethylene in the presence of CO over palladium supported on the graphite-like material Sibunit has been investigated. Carbon monoxide is an effective modifier of the selective hydrogenation process, exerting its effect by competing with acetylene and ethylene for chemisorption sites on the palladium surface. Under the optimum conditions (T = 90°C; N-methylpyrrolidone solvent; feed consisting of 2 vol % C2H2, 90 vol % H2, and He balance), the introduction of 2 vol % CO ensures a high ethylene selectivity of 89.6 ± 1.5% at an acetylene conversion of 95.8 ± 1.3%, with the acetylene converted into hydrooligomers taken into account.

The interaction between tert-butyl chloride and activated aluminum was studied by attenuated total reflectance Fourier transform infrared spectroscopy near room temperature (18–25°C). A long induction period of ∼240–260 min was observed. The ionic aluminum chloride complexes [Al n Cl3n+1]− (n = 1, 2) and the molecular species AlCl3 were identified at the activated aluminum/tert-butyl chloride interface during the reaction. The formation of the ion in the AlCl 4 − ion in the liquid medium and the presence of the same ion and a molecular AlCl3-tert-butyl chloride complex in the resinous products of the reaction were confirmed by 27Al NMR spectroscopy. The reaction products were analyzed qualitatively by GC/MS. The reactivities of activated aluminum and anhydrous aluminum chloride toward tert-butyl chloride under the same conditions were compared. A distinctive feature of the interaction activated aluminum and tert-butyl chloride is the dominant formation of the AlCl 4 − ion. By contrast, the interaction between aluminum chloride and tert-butyl chloride yields the polynuclear ion Al2Cl 7 − and, likely, Al3Cl 10 − .