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The effect of Si/Al ratio of zeolite Y on the performance of NiW catalysts for second stage hydrocracking was studied. The zeolites were characterized by IR spectroscopy of adsorbed pyridine, low-temperature N2 adsorption, and temperature-programmed desorption of ammonia. The observed decrease of Bronsted and Lewis acid sites concentration relates to the increase of Si/Al ratio in zeolites. According to HRTEM and XPS, sulfide component of catalysts differs in morphology, NiWS phase content and tungsten sulfidation degree. The catalysts were tested in hydrocracking of model (squalane) and real feedstock (unconverted oil (UCO) from two-stage industrial hydrocracker) at different temperatures. The increase of Si/Al ratio in zeolites was found to result in the decrease of catalytic activity and the increase of selectivity to middle distillates. However, similar selectivity of 52 and 53% at the 50% of UCO conversion was observed for catalysts containing zeolites with Si/Al ratio 24 and 37 respectively. This can be attributed mainly to the differences in the textural properties of the zeolites. The catalyst based on amorphous silica-alumina (without zeolites) was found to have a higher selectivity to middle distillates and lower activity as compared to zeolite-based catalysts.

The present work studies the influence of nitrogen compounds in hydrotreated fluid catalytic cracking (FCC) feedstock on the material balance of FCC process focused on petrochemistry. Vacuum gas oil was hydrotreated at the temperatures of 340–370 °C in typical FCC pretreatment conditions. The obtained hydrotreated products contained 370−750 ppm of nitrogen and 150−820 ppm of sulfur. Hydrotreated feedstock was exposed to the FCC process over a zeolite catalyst at the laboratory unit with a fixed bed catalyst at 527 °C and catalyst/oil ratio - 2−6. The FCC feedstock before and after hydrotreatment and FCC products were characterized by different methods to study the effect of nitrogen compounds on the FCC process.

Special features of the process of recrystallization of austenite under hot deformation and its effect on the physical and mechanical properties of rolled sections from bearing and structural steels under the conditions of thermal deformation treatment are studied.

The paper considers the features of modification of wood (pine) with reactive copolymers based on glycidyl methacrylate and fluorine (alkyl) methacrylates to impart water-repellent properties. Such modification provides the achievement of superhydrophobic properties and a decrease in the water permeability of the material due to a smaller spot of contact of water drops with the surface. Wood water absorption index reduced by 3 times.

The article presents the results of a study of the properties of chitosan spongy materials (aerogels) surface modified with copolymers of glycidyl methacrylate. The surface of the obtained materials is characterized by a highly hydrophobic state with contact angles at the initial time moment more than 140 degrees, while a decrease in water absorption of aerogels and a slight decrease in oil absorption are also observed as a result of the modification.

The influence of alumina precursors on NiMo/γ-Al2O3 catalysts for silicon removal from gas oil have been studied. Alumina precursors were prepared by hydrothermal treatment of gibbsite, precipitation of aluminum nitrate by ammonia and precipitation of aluminum nitrate in autoclave. Alumina precursors, supports and catalysts were studied by XRD, nitrogen adsorption-desorption, IR spectroscopy, UV–vis, XPS, SEM, HRTEM. Series of NiMo/γ-Al2O3 catalysts differed in preparation method of alumina precursors was tested in hydrotreating of diesel fraction contaminated with decamethylcyclopentasiloxane as a model silicon compound. It was shown that prepared alumina precursors were boehmites and dawsonite, which had different particle size. The supports prepared from these alumina precursors were γ-Al2O3 with different particles size. It was shown that there was a dependence of the surface area of the support on the size of primary particles measured by XRD. The higher surface area results in the higher content of OH groups and silicon sorption capacity. Morphology of the sulfide active component also depends on the size of primary particles. The higher length of the particles, the higher slab length of NiMoS phase. The catalyst with the lowest particle size of alumina and highest length of active component had the highest HDS activity.

The influence of alumina precursors on catalytic activity CoMoP/Al2O3 hydrotreating catalysts has been studied. Alumina precursors were prepared by eco-friendly technology including hydrothermal treatment at different stabilization time of a flash calcined gibbsite. One sample was synthesized with the addition of boric acid. A reference sample of pseudoboehmite was obtained by precipitation from aluminum nitrate with aqueous ammonia. Alumina precursors, supports and catalysts were studied by XRD, nitrogen adsorption/desorption, XPS, HRTEM. CoMoP/Al2O3 catalysts were tested in hydrotreating of model feed and fuel mixture. It is shown that the samples obtained from the product of flash calcination of gibbsite, besides pseudoboehmite, also include the amorphous phase, while the reference sample, synthesized by precipitation, is a pure pseudoboehmite. The introduction of boron prevents the crystallization of pseudoboehmite. Textural properties of the catalysts depend of initial support: alumina samples prepared by hydrothermal treatment have a bimodal pore distribution with peaks at 60–70 A and 150–200 A, the support synthesized through reprecipitation has a unimodal distribution with a maximum at 80 A. The initial alumina used as a catalyst support has a significant impact on the share of CoMoS phase of type II. The highest activities in the hydrotreating of model feed (dibenzothiophene, quinoline and naphthalene in undecane) and fuel mixture shown catalyst prepared using hydrothermal treatment of flash calcined gibbsite without addition boric acid and with short stabilization time.

We suggest a simple and reproducible strategy for fabricating durable superhydrophobic coatings on the basis of series of functional random copolymers of alkyl methacrylates and glycidyl methacrylate on cotton fabric surface. The procedure consists of the fabric treatment by solutions of copolymers in methylethylketone and following heating at 140 °C. The initial contact angles of obtained coatings on fabric surface achieve 165°. The dependence of superhydrophobic properties of coatings based on copolymers of glycidyl methacrylate and alkyl (meth)acrylates (with alkyl radicals С4–С18 in side chains) attached to the cotton fabric surface was studied. The comparative analysis of superhydrophobic state stability of polymer coatings during long-term contacts with aggressive media is presented. We evaluated the contact angles stability as a function of prolonged contact of polymer coatings with water under saturated vapor conditions, organic solvents, and synthetic detergents. Polymeric coatings based on a copolymer of lauryl methacrylate (С12) and glycidyl methacrylate provide better stability of superhydrophobic properties compared with other copolymers of alkyl methacrylates.

A study has been made of the hydrodynamic characteristics of the transition of a multicomponent bed consisting of coal sludge and straw pellets to a fluidized state. It has been shown that increase in the fraction of large particles (pellets) in the bed leads to a decrease in its relative height and in the amplitude of pulsations of the pressure difference in it; this contributes to the rise in the degree of conversion of chemical reations occurring in the bed. The possibility of assessing the minimum fluidization velocity of a multicomponent bed from the dependence of the standard deviation of a pulsation of the pressure difference in it on the velocity of air blown though the bed has been proved.

Zeolites of the MTT framework type (Si/Al = 30) have been synthesized using dimethylformamide as a template and by a template-free method (Si/Al = 24). The morphology, textural, and acidic properties of the synthesized zeolites have been studied by scanning electron microscopy, high-resolution transmission electron microscopy, N2 adsorption, IR spectroscopy of adsorbed pyridine, and temperature-programmed desorption of ammonia and compared with the properties of a commercial ZSM-23 zeolite (Si/Al = 24). Zeolite powders have been used to prepare ZSM-23+Al2O3 supports and then Pt-modified bifunctional catalysts, the properties of which have been tested in n-decane hydroconversion. It has been shown that the isomerization activity of the Pt/ZSM-23/Al2O3 catalysts is largely determined by the texture and morphology of the original zeolites.

Water-loving compounds are usually used to prepare superhydrophilic and underwater superoleophobic surfaces. Hydrophilic polymers especially polyelectrolytes which contain the charged units in their structure is one of the perspective classes for the creation of materials with superhydrophilic properties. In this work, grafted polyelectrolytes based on quaternized N,N-dimethylaminoethyl methacrylate and sodium methacrylate were synthesized on the textured aluminum surface with an attached anchor layer (polyglycidyl methacrylate) and the initiator (2-bromo-2-methylpropionyl bromide) using surface-initiated atom transfer radical polymerization. The texturing of aluminum surface was performed using sequential etching in alkali and acid solutions. The lyophilic properties of grafted polyelectrolytes were studied by contact angle measurements using the “sessile drop” and “captive bubble” methods. The resulting coatings exhibit superhydrophilic properties due to quaternized ammonium and carboxyl charged groups in the grafted polyelectrolytes. Specifically, the coatings show complete wetting with water, stable aerophobicity and oleophobicity in aqueous media, and the demonstrated contact angles are greater than 170° for long contact times. It has been shown that grafting of polyelectrolytes prevents the sorption of nonpolar organic pollutants on the modified surface.

In this paper the influence of dispersed catalysts obtained in situ based on various metals (Mo, Ni, Fe, Co) has been studied on the yield and properties of liquid products in a slurry-reactorat a temperature of 425 °С and a pressure of 20 MPa. The most active catalytic compositions for the process of catalytic steam cracking of oil (Mo and Mo-Fe) were selected. In the presence of dispersed Mo and Mo-Fe catalysts the samples of the semisynthetic oils were produced. In the rectification process the gasoline, diesel, oil and residual fractions were allocated. The selected fractions were analyzed by physicochemical methods for a wide range of performance in comparison with the initial heavy oil. The efficiency of Mo-Fe catalysts for obtaining semisynthetic oil with an increased content of light fractions (i.b.p. – 360 °С) during the catalytic steam cracking of heavy oil was shown

The influence of the composition and structure of copolymers based on fluoroalkyl methacrylates with a low fluorine content in the monomer unit (from 3 to 7 atoms) on the stability of the superhydrophobic state in the mode of heterogeneous wetting of the surface of grade 304 stainless steel, which was preliminarily etched in hydrofluoric acid, is studied. The characteristics of the hierarchical texture of the steel surface, in particular, the depth of etching and penetration of polymer modifiers, are investigated. Superhydrophobic polymer coatings on stainless steel remain in the heterogeneous wetting regime for more than two days when a droplet of water is in continuous contact with the surface of the sample under saturated conditions: the contact angle changes from 168° to 155°.

Regular features of the effect of recrystallization of austenite under hot deformation on the formation of structure in thermal deformation treatment (with subsequent hold in the furnace and without it) of rolled sections from corrosion-resistant austenitic chromium-nickel steels 10Kh17N13M2T (EI-447) and 12Kh18N19MT are investigated. The kinetics of the austenite recrystallization is studied by metallography and measurement of the hardness of specimens and of the microhardness of recrystallized and not recrystallized grains. The volume of the recrystallized grains and their mean size are determined. The effect of the homogenizing modes in heating for quenching, and of accelerated and decelerated cooling after rolling in a 1050/950 rolling mill of the “Dneprospetsstal’” Company on the impact toughness of the steels is studied.

Design of the planar magnetron-injection gun (MIG) forming ribbon helical electron beam (HEB) suitable for use in new generation of powerful planar gyrotrons is developed. The presented approach is based on three-dimensional numerical simulation of electron-optic system with taking into account the real three-dimensional configuration of the electrodes, beam space charge forces and such specific for MIGs factors as roughness of the emission surface and thermal velocities of electrons. Special attention was paid to the effect of particles drift in crossed electric and magnetic fields. Recommendations to diminish the velocity spread in the regimes with high enough (more than 1.3-1.4) pitch-factor are given. An analyzer of ribbon HEBs based on the retarding electric field method is proposed and optimized. The results of theoretical studies are in good agreement with the experimental data obtained at the IAP RAS by the mentioned above analyzer.

The problem of optimizing the textural characteristics and chemical composition of the alumina support of a vacuum gasoil hydrotreating catalyst is considered. The catalyst is synthesized using the state-of-the-art environmentally friendly technology of flash calcination of gibbsite. Ways of increasing its specific surface area by introducing inorganic additives containing boron or sulfur at the stage of synthesizing boehmite with needle-shaped particles are developed. It is established that introducing such modifiers raises SBET by 50–100 m2/g, relative to the maximum values that can be attained by varying the standard parameters of hydrothermal treatment. It is shown that introducing boron at the stage of boehmite synthesis improves the catalytic activity of CoNiMoP catalyst in the hydrodesulfurization and hydrodenitrogenation of vacuum gasoil by two or more times, relative to a similar catalyst doped with boron from an impregnating solution.

The influence of textural characteristics of NiMo/Al2O3 on silicon capacity and hydrotreating activity has been investigated so as to develop guard-bed catalyst for silicon removal from middle distillates. Series of NiMo/Al2O3 catalysts with a specific surface area from 150 to 210 m2/g and an average pore diameter from 21.1 to 10.5 nm have been synthesized. The difference in textural characteristics has been achieved by variation of aging time and temperature of hydrothermal treatment of boehmites. The boehmites, supports and catalysts were studied by various physico-chemical methods: XRD, nitrogen adsorption-desorption, IR spectroscopy, UV–vis, 1H NMR, 27Al NMR, XPS, SEM, HRTEM. Catalysts were tested in hydrotreating of diesel fuel contaminated with decamethylcyclopentasiloxane as a model silicon compound. It is shown that the increase in aging time and temperature of hydrothermal treatment of initial boehmites results in the decrease of OH groups concentration per 1 g of an alumina support. The increase of the OH groups content leads to higher silicon capacity, while HDS activity of catalysts decreases. The study of catalysts surface after reaction showed that Si located on a support surface and did not cover directly active component particles. However, its location on the support near edges of active component particles could result in the decrease of HDS activity due to limited accessibility of the active sites.

The effect of ultrastable zeolite Y recrystallization on the properties of NiMo/USY-Al2O3 hydrocracking catalyst has been studied. The mesoporosity, being introduced as the result of zeolite Y recrystallization, is mainly preserved at the subsequent steps of NiMo catalysts preparation. The total concentration of Bronsted acid sites in the catalysts varies proportionally to that for the corresponding zeolites used for preparation. It is observed that the higher the recrystallization degree the lower the concentration of strong Bronsted acid sites in the catalysts. UV–vis DRS, HRTEM and XPS data suggest that the state of supported Ni and Mo is similar for the catalysts prepared with parent and recrystallized zeolites. The catalysts based on recrystallized zeolites have significantly higher activity in hexadecane hydrocracking as compared to the catalyst obtained using parent zeolite. This effect is rationalized in terms of the improved accessibility of zeolite acid sites after recrystallization. Moreover, the mesoporosity introduced by zeolite Y recrystallization has a positive effect on the selectivity of NiMo/USY-Al2O3 hydrocracking catalyst.

Under discussion is optimization of texture and chemical composition of alumina as the support for the catalyst for hydrotreatment of vacuum gasoil synthesized using the environmentally friendly modern technology of flash thermal treatment of gibbsite. Approaches to increasing the specific surface area by introducing inorganic admixtures (including boron or sulfur) at the stage of synthesis of pseudoboehmite were developed. The introduction of these modifiers was established to increase SBET by 50–100 m2/g comparing to the maximal areas attaineddue to variation in the standard process parameters of the hydrothermal treatment. It was shown that the introduction of boron at the stage of pseudoboehmite synthesis resulted in no less than two times increase in the catalytic activity of CoNiMoP to hydrodesulfurization and hydrodenitrogenation against the activity of a similar catalyst with boron introduced with the impregnating solution.

The multivalence of vanadium in oxide melts is considered. It is shown that the vanadium oxidation state in the slags is determined by the slag and metal compositions as well as the oxidation potential of the gas phase. Using a polymer model, vanadium valence form fractions were calculated depending on technological parameters. Calculations show that in an air atmosphere, vanadium in the slag should be predominantly in the tetravalent and trivalent state, and in contact with the molten iron, mainly in the trivalent and partly divalent state. Upon contact with pig iron, VO oxide becomes the main form of vanadium in the slag. Slag basicity and temperature have a significant effect on the relationship of vanadium forms. The suggested design-basis using the polymer model can be useful in accomplishment of the thermodynamic calculations for the vanadium equilibrium distribution between metal and slag in the iron and steel production. It allows us to describe the dependence of the vanadium oxidation state on the free oxygen activity in the slag and the gas phase oxidation potential.

Novel eco-friendly method for preparation of mesoporous alumina from the product of rapid thermal treatment of gibbsite (CTA product) without “reprecipitation” stage is described. Compared with the nitrate-ammonia technology of “reprecipitation” of gibbsite to boehmite and its further calcination to γ-Al2O3, the new method consumed less amount of HNO3 per 1 kg of Al2O3 (by 30 times), while the amount of effluents is twice lower. Effluents do not contain ammonium nitrate, since the preparation of boehmite does not include ammonia. It is shown that the method makes it possible to obtain boehmite with needle-shaped particle morphology. The particle size of boehmite and the textural characteristics of alumina are easily adjusted over a wide range by changing the temperature, aging time or peptizing agent. Thus, the pore volume of alumina may be 0.45–0.95 cm3/g with an average pore diameter of 81–256 A and SBET = 140–240 m2/g.

CoMoB/Al2O3 catalysts with up to 2 wt.% of B have been synthesized by two different methods an introduction of boron into γ-Al2O3 support during the kneading of the paste or by the impregnating of γ-Al2O3 extrudates by the solution of Mo and Co compounds, citric and boric acids. It is shown that the activity in HDS and HDN of diesel fuel increases with increasing boron content in catalysts. The growth of the activity is associated with the increase in CoMoS phase content, Co dispersity, an average slab length of sulfide active component particles and an average number of slabs per 1000 nm2. The positive effect of boron is much more pronounced for catalysts prepared by the introduction of boron to the solution, since boron is located preferentially on the surface of alumina particles.

Hydrocracking of vacuum gas oil was studied over micro-mesoporous zeolite based catalysts, obtained by zeolite Y recrystallization. The contribution of mesoporosity in recrystallized materials was varied by adjusting the content of alkali and the temperature of hydrothermal treatment. The increase of recrystallization degree results in the increase of mesopore to micropore volume of zeolite Y as well as to the decrease of the contribution of strong Bronsted acid sites in faujasite cages and the increase of the contribution of Bronsted acid sites in mesopores. The highest hydrocracking activity and middle distillates yield is achieved over NiMo catalyst obtained with micro-mesoporous material with low degree of recrystallization. This effect is due to the improved accessibility of active sites and easier transport of bulky molecules provided by mesopores, on the one hand, and optimal zeolitic acidity, on the other hand. The highest selectivity to middle distillates is achieved over catalyst with the highest degree of zeolite recrystallization. This observation can be explained by the decrease of the contribution of strong BAS (bridging Si-O(H)-Al groups) accompanied by the increase of concentration of BAS in mesopores.

In the present work, NiW/Al 2 O 3 catalyst was prepared with the use of citric acid and thermally treated at temperatures of 120, 220, 300 and 450 °C. It was shown that the thermal treatment at temperatures of 220–300 °C leads to decomposition of citrate ligands, 450 °C – to the almost complete removal of organic carbon. HRTEM of the sulfided catalysts showed that stacking number of WS 2 increases with the increase of the thermal treatment temperature while the WS 2 slab length has minimum at 220 °C. The results of XPS indicated that the sulfidation degree of tungsten and nickel decreases with the increase of the thermal treatment temperature. The catalyst thermally treated at 300 °C resulted to be most active in DBT HDS, quinoline HDN and naphthalene hydrogenation reactions. The higher activity of this catalyst in comparison with the samples thermally treated at 120 °C and 220 °C can be explained by an increased stacking degree of the sulfide WS 2 slabs while maintaining a small length of sulfide slabs and by a smaller carbon content that can impede access to the active sites. The calcination at 450 °C leads to low activity due to the low dispersion of the active component and a decrease in the degree of sulfidation of tungsten and nickel.

Ni-Mo bimetallic catalysts are prepared by impregnating a carrier containing amorphous aluminosilicate (AAS) and aluminum oxide using a solution with Ni, Mo, and citric acid. The temperature of the catalysts ranges from 120 to 550°С. The physicochemical properties of the catalysts are studied via XPS, TEM, and HCNS analysis, and they are tested in hydrocracking of vacuum gasoil. The particles of the sulfide active component (NiMoS phase) are localized predominantly on surfaces of aluminum oxide, and only some are on surfaces of AAS. When the temperature of catalyst calcination is raised, the average number of the layers in particles of the NiMoS phase grows as well, due to the removal of citric acid. This indicates strengthening of the interaction between the sulfide active component and aluminum oxide. The content of Ni-Mo massive sulfide particles also grows along with the temperature of calcination. The morphological characteristics of the sulfide active component affect the activity of the catalysts in hydrodesulfurization and hydrodenitrogenation, but not in hydrocracking. The optimum heat treatment temperature for NiMo/AAS-Al2O3 catalysts prepared with citric acid is 120°C. Recommendations are given for the heat treatment of catalysts under industrial conditions.

The effect of the W: (W + Mo) atomic ratio in NiMoW trimetallic catalysts on their catalytic and physicochemical properties is studied. The catalysts are prepared by impregnating a carrier containing amorphous aluminosilicate (AAS) and aluminium oxide with an aqueous solution containing Ni, Mo, W compounds, and citric acid. They are studied via XRF, TEM, NH3 TPD, and low-temperature nitrogen adsorption and are tested in the hydrocracking of vacuum gasoil (VGO). The average length of a sulfide active component layer shrinks as the amount of Mo increases and the amount of W in the catalyst is reduced. XPS data indicate that the degree of sulfidation of tungsten in NiMoW trimetallic catalysts is lower than in NiW catalyst. Testing of the catalysts in hydrocracking of a straight-line VGO at 390–420°C, 16 MPa, a feedstock hourly space velocity (FHSV) of 0.71 h−1, and a H2: VGO ratio of 1200 L/L shows the activities of hydrodesulfurization, hydrodenitrogenation, hydrogenation, and hydrocracking grow along with the W: (W + Mo) ratio. When the process pressure is high and the amount of sulfur in the NiW feedstock is low, the catalysts have higher activity in the target reactions of VGO hydrocracking than NiMo catalyst.

The influence of the order of catalysts and their ratio in the bed for FCC feedstock hydrotreatment was investigated. CoMo/Al2O3 and NiMo/Al2O3 catalysts were prepared in the laboratory and studied by nitrogen adsorption–desorption, XPS and HRTEM methods. The catalysts were tested in hydrotreatment of model feedstocks. It was found that NiMo/Al2O3 catalyst had the highest activity in conversion of the model feedstock containing sulfur and nitrogen compounds. The best results were obtained for the feedstock firstly treated by NiMo/Al2O3 and then by CoMo/Al2O3. Catalysts were tested separately and together in hydrotreatment of SRVGO. The order of catalysts and their ratio were varied. The best combination included NiMo/Al2O3 catalyst at the top of the reactor and CoMo/Al2O3 at the bottom of the reactor in the ratio of 40/60 vol%.

The influence of various characteristics of NiMo/Al2O3 guard-bed catalysts on their activity in the removal of silicon from the diesel fraction has been studied. It has been shown that an increase in the Ni and Mo content leads to a decrease in the amount of trapped silicon in the samples, thereby enhancing the activity of the catalysts in hydrodesulfurization. It has been found that catalysts with an average pore diameter above 130 A have the highest silicon-trapping activity.

This study involved the modification of a textured aluminum surface with reactive fluoroalkyl methacrylate copolymers with short-chain fluoroalkyl radicals and glycidyl methacrylate to achieve superhydrophobic properties. The resulting grafted polymer coatings are characterized by contact angles up to 170° and roll-off angles of 2–3°. The multimodal texture of the modified aluminum surface layer, namely, the etching depth and the penetration depth of polymeric modifiers, has been investigated by scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS). This study demonstrates an increase in the stability of the heterogeneous wetting regime of superhydrophobic coatings based on fluoroalkyl methacrylate copolymers due to multiple attachment of the polymeric modifier to the surface.

We propose a novel approach to create a superhydrophobic coating on an aluminum surface by attaching random copolymers that are based on glycidyl methacrylate and a number of fluoroalkyl methacrylates that contain 3–7 fluorine atoms in their monomer units. To texture the aluminum surface, short-term etching with hydrochloric acid solutions was used. The coatings that are based on glycidyl methacrylate and fluoroalkyl methacrylate copolymers maintain superhydrophobic properties for longer than 40 h under saturated vapor conditions.

A new CoMo catalyst for selective hydrotreating of FCC gasoline has been developed; the catalyst is intended for the production of hydrotreated gasoline with up to 10 ppm of sulfur and with a research octane number decreased by less than 1.0. The new catalyst allows hydrotreating of FCC gasoline without its preliminary separation into the light and heavy fractions. The hydrotreating conditions were as follows: hourly space velocity 2.2 h–1, temperature 270°C, pressure 2.5 MPa, H2/feed = 150 m3/m3. The high degree of hydrodesulfurization at minimum decrease in the octane number is achieved due to the high activity of the developed catalyst in hydrodesulfurization of the sulfur-containing components of the feedstock and conversion of reactive high-octane olefins of FCC gasoline into less reactive derivatives with high octane numbers. The catalyst is a CoMoS phase deposited on a support containing amorphous aluminosilicate and γ-Al2O3. The method for the preparation of the catalyst is adapted to the equipment of Russian plants and feedstocks. The parameters of hydrotreating using this catalyst ensure the hydrotreating of FCC gasoline to a residual sulfur content of less than 10 ppm with minimum redesign of the equipment currently available at Russian refineries.

An approach to making the surface of a cotton cloth possessing superhydrophobic properties is given consisting in graft polymerization of fluoroalkyl metacrylates by the atom transfer radical polymerization method (ATRP). Poly(glycidyl methacrylate) was used as an anchor layer, followed by fixing of the polymerization initiator. The stability of the hydrophobic properties of the modified cloth under prolonged contact with aqueous media and organic solvents was demonstrated.

The process of heating a granular bed under conditions of thermal fluidization with heat supplied through the upper boundary of the bed and through its gas distributor is investigated.

Hydrocracking of vacuum gas oil has been studied over NiMo/zeolite-Al2O3 catalysts. Three different zeolites have been used for catalysts preparation: zeolites Beta (BEA) and Y (FAU) having small crystal size and zeolite Y modified by recrystallization (RFAU). HRTEM, low-temperature N2 adsorption, FTIR of adsorbed CO and TPD-NH3 showed that zeolites had different crystal sizes, mesopore volume, strength and concentration of acid sites. Sulfide active component particles have been revealed to be similar in all catalysts by HRTEM and XPS. NiMo/BEA catalyst having zeolite with the smallest average particle size and the highest concentration of Bronsted acid sites (BAS) demonstrated the highest hydrocracking activity. Selectivity to middle distillates decreased in the following order: NiMo/FAU > NiMo/RFAU > NiMo/BEA. This effect is accounted for by optimal zeolite acidity and improved availability of the acid sites for bulky molecules of the heavy feedstock.

The results of comparative experiments on the production of biofuel from poultry litter (PL) by the method of low-temperature pyrolysis (Torrefaction) and hydrothermal carbonization are presented. Comparison of the obtained results shows that as a result of hydrothermal carbonation of PL (processing temperature 180-210 °C, treatment time 240 minutes), the carbon content in the manure can be increased by 1.35 times, and the oxygen content is reduced in 2.2 times, the lower heat of combustion of the fuel obtained, which is similar in its characteristics to lignites, can be increased by 1.25 times to 19.7 MJ/kg. As a result of low-temperature pyrolysis in the fluidized bed at a temperature of 300 °C in a nitrogen medium and superheated water vapor, the carbon content can be increased by 1.16 times, and the oxygen content is reduced in 2.8 times. The lowest heat of combustion of the fuel produced can be increase by 1.13 times to 18.8 MJ/kg. Considering that the technology of PL treatment by low-temperature pyrolysis in the fluidized bed requires significantly less processing time (360-480 seconds), this technology can be fully considered as an alternative to hydrothermal carbonization.

The positive effect of alumina surface graphitization by CVD with ethylene on the activity of CoMo catalysts in hydrodesulfurization has been demonstrated. X-ray diffraction, Raman spectroscopy, High-resolution transmission electron microscopy, X-ray photoelectron spectroscopy and nitrogen physisorption showed that alumina surface graphitization does not significantly change the morphology and textural characteristics of the support. However, it has a significant impact on the morphology of supported sulfide component resulting in the formation of particles with a shorter slab length (2.9 vs 3.3 nm) and higher stacking number (2.4 vs 2.1) as compared to the sample based on γ-Al2O3. The results of CoMoS/γ-Al2O3 and CoMoS/C@γ-Al2O3 catalysts testing in hydrotreating reactions demonstrated a similar activity in hydrodenitrogenation of quinoline and 1.7 times higher activity of CoMoS/C@γ-Al2O3 in hydrodesulfurization of dibenzothiophene. Higher hydrodesulfurization activity of CoMoS/C@γ-Al2O3 sample is attributed to improved dispersion of the supported sulfide component and enhanced promotion of MoS2 by cobalt. Thus, the simple CVD approach presented here allows selective modification of the surface of commercially available alumina supports with a layer of graphite-like carbon and can be used to improve the activity of conventional hydrotreating catalysts.

A new approach to optimize grading guard systems for gas oil hydrotreating reactor based on the phenomenon of clogging of catalyst beds with microparticulates and coke deposits was developed. Pellets with different shapes have been tested to obtain dynamic dependencies of filter coefficient and pressure drop buildup. The experiments were performed in the trickle-flow regime with different ensembles of microparticulates having sizes from 15 to 165 μm. The observed effect of a filter cake formation was characterized in terms of average porosity of the interface beds and it was introduced in simulations plugging of catalyst bed. Estimation of the growth of coke deposits was made using modified Voorhies’s equation and experimental samples obtained in the microreactor under hydrotreating process conditions using foulants of industrial gas oil hydrotreater. The analysis of coked samples was carried out using TGA. Based on the discrete model and experimental data, optimization procedure of grading guard systems was carried out using brute force search. All combinations of schemes of guard-beds were compared using integrated hydrodynamic resistance as a criterion. It was shown that an optimized scheme of guard-beds can reduce hydrodynamic resistance as compared to the schemes without guard-beds or with non-optimized guard-beds.

Influence of Si addition at the stage of boehmite preparation on properties of NiMo/Al2O3 catalysts for FCC feedstock pretreatment have been studied. The series of boehmites doped by PDMS at the stage of hydrothermal treatment was prepared. Si/Al molar ratio was 0, 0.01, 0.015 and 0.02. Boehmites were used for supports and catalysts preparation. Boehmites, supports and catalysts have been characterized by XRD, TGA, nitrogen adsorption-desorption, IR spectroscopy, UV–Vis, 29Si MAS NMR, HRTEM, EDX, XPS. Catalysts were tested in hydrotreating of FCC feedstock. It is shown that there are changes in morphology of boehmite particles and textural characteristics of aluminas. Introduction of Si to alumina induces formation of wider mesopores and blocks part of the Lewis acid sites of alumina. Testing of catalysts in hydrotreating of FCC feedstock shows that the catalyst with Si/Al ratio of 0.01 in boehmite has the best combination of hydrodesulfurization and hydrodenitrogenation activities.

Modification of cotton fabric surface by random or block copolymers of glycidyl methacrylate and lauryl methacrylate is studied. It is shown that a cotton fabric surface modified in such a way takes on superhydrophobic properties and differs in stability under long-term contact with aqueous media.

The method for preparation of Co–Mo catalysts for one-stage hydrotreating of full FCC gasoline fraction is proposed. The main characteristic of the catalysts is the use of the supports based on amorphous aluminosilicate. Catalysts were characterized with nitrogen adsorption-desorption, HRTEM and XPS methods. It was shown that all catalysts containing aluminosilicates have similar textural characteristics and contain Co-Mo-S phase with similar morphology. The IR CO data indicate that sulfided catalysts contain different acid sites with the predominance of weak Lewis acid sites and Bronsted acid sites with the strength of 1190 kJ/mol. Catalysts were tested in hydrotreating of model fuel and full FCC gasoline fraction. It was shown that presence of amorphous aluminosilicates in catalysts results in the increase of catalytic activity in reactions of olefin isomerisation. Significant contribution of olefin isomerization reactions results in the prevention of octane number loss while high activity hydrodesulfurisation maintains.

Nowadays, computational techniques can greatly facilitate the identification of point defect related photoluminescence and EPR centers in semiconductors. Once the identification has been achieved, one can gain a detailed description of the microstructure and the electron configuration of the defect, providing a basis for further understanding and development. Recently, the importance of divacancy and related point defects in different polytypes of SiC has substantially increased due to their possible quantum bit application. However, their different configurations have not been satisfactorily identified yet. In our study, we carry out large-scale first principles supercell calculations to identify the divacancy related point defects in 4H and 6H-SiC. By resolving some general accuracy issues of usual ab initio supercell techniques, we are able to obtain convergent photoluminescence (PL) energies, zero-field-splitting, and hyperfine parameters. Our results confirm the previous assignment of the PL1-4 PL lines in 4H-SiC (also known as UD-2 luminescence lines previously) to the four possible divacancy configurations and provide the identification of QL1,QL2, and QL6 PL lines in 6H-SiC. In all cases the calculated zero-field and hyperfine tensors’ parameters are provided.

We demonstrate optically pumped dynamic nuclear polarization (DNP) of 29Si nuclear spins that are strongly coupled to paramagnetic color centers in 4H- and 6H-SiC. We observe 99%±1% degree of polarization. By combining ab initio theory with the experimental identification of the color centers’ optically excited states, we quantitatively model how the polarization derives from hyperfine-mediated level anticrossings. In addition, we developed a general model for these optical DNP processes that allows the effects of many microscopic processes to be integrated. Applying this theory, we gain a deeper insight into dynamic nuclear spin polarization. In particular, our findings show that the defect electron spin coherence times and excited state lifetimes are crucial factors in the entire DNP process. These results lay a foundation for SiC-based quantum memories, nuclear gyroscopes, and hyperpolarized probes for magnetic resonance imaging.

Oxidation catalysts, e.g., those for biomass combustion in a fluidized bed (olivine sand and catalyst ShchKZ-1), were compared. Samples consisting of straw powder, straw powder and uncalcined olivine sand, straw powder and calcined olivine sand, and straw powder and crushed catalyst ShchKZ-1 were prepared. The calcined olivine sand and catalyst ShchKZ-1 had practically the same influence on the sample mass loss and heat generation from the straw by heating.

We develop a high speed on-chip flux measurement using a capacitively shunted SQUID as an embedded cryogenic transducer and apply this technique to the qualification of a near-term scalable printed circuit board (PCB) package for frequency tunable superconducting qubits. The transducer is a flux tunable LC resonator where applied flux changes the resonant frequency. We apply a microwave tone to probe this frequency and use a time-domain homodyne measurement to extract the reflected phase as a function of flux applied to the SQUID. The transducer response bandwidth is 2.6 GHz with a maximum gain of $\rm 1200^\circ/\Phi_0$ allowing us to study the settling amplitude to better than 0.1%. We use this technique to characterize on-chip bias line routing and a variety of PCB based packages and demonstrate that step response settling can vary by orders of magnitude in both settling time and amplitude depending on if normal or superconducting materials are used. By plating copper PCBs in aluminum we measure a step response consistent with the packaging used for existing high-fidelity qubits.

The stacked beds comprising hydrotreating catalyst as the top layer, hydrocracking catalyst based on amorphous silica-alumina as the interlayer and hydrocracking catalyst based on USY zeolite as the bottom layer were tested in hydrocracking of mixed feed containing straight-run VGO, heavy coker gas oil, aromatic extract and petrolatum. It is shown that stacked beds with developed catalysts can be successfully used both in the once-through hydrocracking to provide VGO conversion of 70–80% with middle distillates yields up to 50 wt% and in the first stage operation of two stages hydrocracker to provide 35–65% VGO conversion and produce high-quality middle distillates and feed for the second stage. The commercial partner of this work is Gazprom Neft PJSC (Gazprom Neft Omsk Refinery).

An experimental study has been made of the distributions of the coefficient of external heat exchange over the volume of the fluidized bed with different forms of inlet gas distribution. It has been shown that the grid giving a concave inlet profile of the air velocity ensures a required homogeneity of the bed′s structure at a high level of heat exchange.

Results of determination of effective heat capacity of untreated biomass granules are furnished. It is shown that evaporation of moisture and other volatile components present in the material affects heat absorption by the material. A mathematical model of the temperature field in reactor chambers during low-temperature biomass pyrolysis is given.