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Nowadays, the production of liquid motor fuel faces such problems as compliance of the final product with existing international standards (for the content of sulfur, oxygen and nitrogen) as well as the improvement of the feasibility of the existing technologies for fuel production. Biomass is one of the most perspective and widely spread sources for energy. The existing techniques for biomass conversion into the fuels are mainly based on the hydroprocessing and can be successfully applied in petroleum industry. The integrated processes involving both biofuel and oil conversion are of great interest. In this work, the novel hydrogen-free approach for co-processing of heavy oil fractions and bio-oil is described. The use of supercritical solvent mixture, which includes propanol-2 and n-hexane, allows full substrate conversion to be achieved for maximum 3 h. As a result, the hydrocarbon mixture consisting of aromatic and cyclic compounds was obtained with 99 wt. % yield.

In this paper, the synthesis of novel effective biocatalysts based on oxidoreductases (peroxidase extracted from the horseradish roots; commercial glucose oxidase) immobilized on the sodium alginate microspheres was performed. To activate the carboxylic groups of the support, enzyme immobilization on the sodium alginate microspheres was carried out using carbodiimide and N-hydroxysuccinimide. This allows the successful crosslinking of enzyme and support to be reached. The investigation of catalytic properties of the synthesized biocatalysts was carried out in the oxidation of phenol and 4-chlorophenol in the presence of 4-amino antipyrine. The activity and stability of the synthesized biocatalysts was studied. The use of biocatalysts immobilized on the sodium alginate microspheres allows more than 95 % of phenol and 4-chlorophenol conversion to be achieved. The synthesized biocatalysts exhibit 25 - 30 % activity in comparison with the native enzyme in the oxidation of phenol and its derivatives. The biocatalysts were found to save their activity in the up to 10 multiple reuses.

A new Ru-containing catalyst based on Fe3O4-SiO2 particles that exhibit magnetic properties is proposed for the hydrogenolysis of cellulose to glycols and the hydrolytic hydrogenation of inulin to mannitol. Here, we also report utilisation of a magnetically recoverable catalyst in the inulin hydrolytic hydrogenation to mannitol. The effect of process parameters on the selectivity toward the main products is studied. In the hydrogenolysis of cellulose, the highest selectivities for EG (19.1 %) and PG (20.9 %) are achieved within 50 min under conditions of 255 °C, H2 60 bar. The conversion of cellulose is 100 %. In the hydrolytic hydrogenation of inulin, maximum mannitol selectivity (44.3 %) is reached within 45 min under conditions of 150 °C, H2 60 bar. The conversion of inulin is 100 %.The catalyst used in this work is stable under hydrothermal conditions of the process. It can be easily magnetically separated from the reaction mixture and reused without any loss of selectivity and activity, making this catalyst promising for practical applications in biomass conversion.

The selective oxidation of organic compounds to obtain vitamins is one of the key processes in chemistry and biotechnology. The use of toxic compounds such as chromium and manganese oxides for these purposes strongly affects the environment. We propose a novel bio-catalyst supported on magnetically separable nanoparticles based on the immobilized peroxidase. Biocatalysts based on immobilized enzymes received considerable attention due to important applications in syntheses of value-added chemicals, pharmaceuticals and drug intermediates with great catalytic efficiency and high yields of target molecules. In this work, we studied the oxidation of 2,3,6-trimethylphenol to 2,3,5-trimethylhydroquinone (an intermediate of vitamin E) using hydrogen peroxide. The effects of initial substrate concentration, temperature, and pH were studied. The optimum conditions for the process of oxidation 2,3,6-trimethylphenol in the presence of magnetically separable biocatalyst were found: initial substrate concentration – 1.5 mmol/L; temperature – 40 °C; pH – 6.5. The developed biocatalyst showed high activity and selectivity in 2,3,6-trimethylphenol oxidation to 2,3,5-trimethylhydroquinone.

Furfural (FF) is one of the main components of bio-oil obtained by the treatment of lignocellulose biomass. Furfural alcohol (FA) as the main product of the selective FF hydrogenation is a source of value-added chemicals. In this paper, the results of the study of ruthenium catalysts based on hyper-crosslinked polystyrene (PS) in the selective hydrogenation of FF to FA are presented. Two types of ruthenium catalysts: nanoparticles of RuO2 and Ru0 stabilized in the PS pores were synthesized and compared. The novelty of this work is in the comparison of the PS stabilized Ru0 and RuO2 nanoparticles were performed and differences in their catalytic properties were shown. The BET, TEM, and SAXS data showed the formation of Ru-containing nanoparticles similar in size and structure for both catalysts. The comparison of the catalytic properties of the Ru catalysts showed that the catalyst with Ru0 (Ru-PS) exhibits higher values of FF conversion (99 %) and selectivity to FA (96 %). It can be assumed that Ru0 nanoparticles are responsible for the formation of catalytically active sites of selective hydrogenation of FF to FA.

In this paper, the commercial 5%Pd/C and 5%Pt/C catalysts and synthesized 5%Pt/MN-270 and 5%Pd/MN-270 were used in the hydrogenolysis of lignocellulosic material (softwood sawdust) to obtain liquid fuels in the form of hydrocarbons. As lignin has a very complex structure, anisole was used as a model compound. It was found that the use Pt-containing catalysts based on hypercrosslinked polystyrene in both processes of anisole and lignin-containing feedstock conversion allowed obtaining the highest yield of oxygen-free hydrocarbons (up to 96 wt. %). Besides, the polymer based catalysts showed high stability in hydrogenolysis process in comparison with the commercial carbon based catalysts.

This paper describes synthesis of Pd-containing catalysts of Suzuki cross-coupling based on non-functionalized hyper-crosslinked polystyrene (HPS) at variation of Pd precursor nature (PdCl2, PdCl2(CH3CN)2 or PdCl2(PhCN)2). Relatively low affinity of Pd species to the chosen polymeric support was shown to be responsible for in situ formation of Pd nanoparticles and their aggregates. During the investigation of aryl halide nature, catalytic activity was shown to decrease in the following order: Br > I > Cl. Best results were obtained for the preliminarily reduced HPS-based sample synthesized while using PdCl2 in the reaction between phenylboronic acid and 4-bromoanisole: more than 93% yield of cross-coupling product was achieved at mild reaction conditions (NaOH, 60oC, solvent ethanol-water mixture) using 0.8 mol.% of Pd.

In this paper, a novel catalysts on the base of hypercrosslinked polystyrene (HPS) with magnetic properties are proposed for the one-pot processes of the cellulose conversion into ethylene glycol (EG) and propylene glycol (PG). Synthesized magnetically recoverable supports and catalysts were characterized by different physical-chemical methods. The magnetic properties of the supports Fe3O4/HPS MN270 and the corresponding catalysts were studied. The use of this catalyst in the process of microcrystalline cellulose hydrogenolysis in subcritical water allows PG and EG selectivities of 20.0 and 22.6%, respectively, at 100% of cellulose conversion.

A study of the structure and catalytic properties of the cobalt- and iron-containing catalysts synthesized by the subcritical deposition in the water medium was performed in the current work. The catalyst synthesis was carried out at a temperature of 200 °C and a total pressure of 7.5 MPa using silica as support. The catalytic activity of the synthesized materials was studied in the liquid-phase Fischer-Tropsch synthesis. The study of catalyst structure and composition showed that the use of silica as catalyst support allows the formation of Co- and Fe-containing particles consisted of metal oxides. Testing of the synthesized catalysts in liquid phase Fischer-Tropsch synthesis showed that Co-based catalyst allowed the formation of gasoline-range hydrocarbons. It is noteworthy that Co/SiO2 showed higher selectivity towards the formation of linear C5-C8 hydrocarbons. In the case of Fe-containing catalyst, the formation of a significant amount of oxygenates (C3-C4 alcohols) was found.

Here, the novel method for the conversion of fatty acids into hydrocarbon fuel without hydrogen consumption is reported. The deoxygenation of stearic acid as a model compound was performed in the medium of supercritical n-hexane in the presence of Ni-containing catalysts synthesized by a hydrothermal deposition method. We studied the influence of the support as well as the metal loading on the yield of target products of stearic acid conversion into hydrocarbons. Ni was supported on the three different supports: anhydrous microporous silica, anhydrous alumina, and non-functionalized hypercrosslinked polystyrene. The hydrothermal synthesis of the catalysts leads to the changes in the porosity and structure of the supports increasing the number of mesopores. The active phase of the catalysts was found to be deposited on the internal surface of the supports as a thin layer of ?-NiOOH. Ni/HPS catalyst was found to be the most active in the stearic acid deoxygenation process in supercritical n-hexane. The study of the influence of the metal loading on the conversion of the substrate and the target product yield showed that 10 wt. % of Ni is more favorable for the production of high yield of C16-C17 hydrocarbons.

The article presents the results of the process of hydrogenolysis of lignin obtained from softwood sawdust using 5% Pt/MN270 and 3% Pt/MN270 catalysts. Depending on the desirable products 2-propanol was chosen as the solvent showing the highest substrate conversion and product yield. Pt polymer-based catalyst provides high substrate conversion compared to Pd catalysts. This can be due to the higher surface area and the higher active metal concentration on the catalyst surface. Also, it is notable, that Pt-containing catalyst results in the lowest formation of oxygen-containing products. The highest conversion (90%) and the highest selectivity towards the oxygen-free hydrocarbons (92%) were achieved while using 5% Pt catalyst based on HPS.

The aim of this work is to develop the synthesis of the magnetically separable biocatalyst for enzymatic oxidation of D-glucose to D-gluconic acid with high product yields. The biocatalyst support is based on magnetite particles (MPs) synthesized by coprecipitation and coated with the amino- silica layer to facilitate further functionalization. This functionalization involves the attachment of the glutaric dialdehyde linker followed by the covalent attachment of glucose oxidase (GOx, an enzyme of oxidoreductase group) via its amino groups. TEM, XRD, and magnetic measurements were performed for initial MPs and GOx biocatalyst. The biocatalyst activity was studied in the oxidation reaction of D-glucose to D-gluconic acid. The biocatalyst synthesis proposed in this work allowed to create a highly effective system. It was found that GOx immobilized on the modified MPs was the most active biocatalytic system in comparison with other inorganic support and showing 88% of gluconic acid yield.

The work is devoted to the modification of H-ZSM-5 samples with sodium hydroxide and oxalic acid to provide the formation of the mesoporous structure of the zeolite and to obtain optimal Si/Al ratio. Moreover, zeolite active sites were modified with Co, Ni, Fe in order to decrease polyaromatic substances formation during methanol transformation into hydrocarbons. The testing of the samples was performed at 350 ºC in a flow reactor, the methanol feed rate was maintained at 0.16 g(methanol)/(g(Cat)*h). Dimethyl ether transformation rate into hydrocarbons was found to be 0.055-0.1 kg(DME)/(kg(Cat)*h) for investigated catalysts. Alkali treatment of H-ZSM-5 samples results in the formation of a mesoporous structure with a mean pore diameter of 5 nm. Formation of additional mesopores results in some increase of dimethyl ether to hydrocarbons transformation rate up to 0.09 kg(DME)/(kg(Cat)*h). Zeolite treatment with oxalic acid results in decreasing of Si/Al ratio from 0.76 to 0.41 that case some decrease of dimethyl ether transformation rate from 0.07 kg(DME)/(kg(Cat)*h) to 0.05 kg(DME)/(kg(Cat)*h), however considerable decrease of polyaromatic hydrocarbons concentration in reaction media was achieved for sample with lowest Si/Al ratio. Modification of H-ZSM-5 with Co, Fe, Ni results in some increase of dimethyl ether transformation rate up to 0.07-0.1 kg(DME)/(kg(Cat)*h) and a considerable decrease of polyaromatic hydrocarbons concentration in reaction media due to active sites modification.The ZSM-5-Ni-0.001M sample showed highest activity 0.1 kg(DME)/(kg(Cat)*h).

Basing on the experimental data the optimal parameters of the pyrolysis of heavy and residual hydrocarbons of oil were defined as follows: temperature of 500 °С; catalyst of CoCl2 with the catalyst loading 5% (wt.) of the substrate weight. Under the optimal conditions the kinetic investigation of the pyrolysis process was carried out using the thermogravimetric method. According to the investigation, it was found that the activation energy of the catalytic pyrolysis of oil-containing waste decreased by 20-30 kJ/mol in comparison to non-catalytic process.

The results of the study of palladium catalysts in the selective hydrogenation of furfural to furfural alcohol are presented. A comparison of the properties of palladium catalytic systems prepared on different supports (aluminium oxide, hypercrosslinked polystyrene and magnetite/hypercrosslinked polystyrene) is carried out. It is shown that the nature of the support has a significant impact on both the morphology of the catalyst and its activity in the selective hydrogenation of furfural. The most effective catalyst was magnetically recoverable 3 % Pd/Fe3O4/HPS, in the presence of which the conversion of furfural was> 95% with selectivity for furfuryl alcohol> 94 %.

In the current investigation, we studied the influence of reaction conditions on the liquid products formation and catalysts stability in methanol to gasoline synthesis process. Methanol to gasoline synthesis was carried out in continuous mode regime. Main reaction products were found to be gases including methane, ethylene, propylene, isobutene, and liquid hydrocarbons including cyclopropane and methylcyclopropane, as well as the aromatics - benzene, toluene, xylene, cresol, durol, naphthalene, methylnaphthalene, ethylnaphthalene, isopropylnaphthalene, methylisopropylnaphthalene etc. The optimal reaction conditions were found to be as the following: 5 bar of the total pressure in the system, 330 ºС process temperature, and methanol feed rate 5 mL/min. The optimal reactor size was found to be 30 cm length and 5 mm diameter. Under the established conditions the yield of the liquid strained hydrocarbons was the maximal and reached about 35 wt. %, while the aromatic content was only 3 wt. %.

This work is devoted to the synthesis of Pd- and Au-containing mono- and bimetallic catalysts based on hypercrosslinked polystyrene (HPS) and study of their catalytic properties in Suzuki cross-coupling of 4-bromoanisole (4-BrAn) and phenylboronic acid (PBA). Series of HPS-based catalysts were synthesized at variation of Pd content and tested in Suzuki cross-coupling of 4-BrAn and PBA in a batch mode at ambient pressure while using ethanol/water mixture as a solvent and NaOH as a base. The highest catalytic activity was observed for Au-Pd/HPS catalyst containing 1.15 wt.% of Pd and 1.80 wt.% of Au andreduced with aqueous solution of NaBH4 (more than 98 %of 4-BrAn conversion was achievedfor 3 h of reaction time). Selectivity was higher than 98 % with respect to 4-methoxybiphenyl (4-MBP). Thus HPS-supported bimetallic palladium catalysts were found to be promising (active, selective) and simple in preparation for the Suzuki cross-coupling at mild temperatures along with the absence of the necessity to use phase-transfer agents.

The disadvantages of most catalysts of gaseous products thermal refining from the tars are their high cost and fast activity loss due to the carbon formed on their surface. So it is necessary to develop cheap and effective catalysts for the thermal refining of pyrolysis gaseous products. Therefore, the study of the fast pyrolysis process including the stage of thermocatalytic refining of pyrolysis gaseous products can help to solve the problems of renewable feedstock processing with the energy generation followed. It was found that the use of zeolite catalysts on the base of iron subgroup metals leads to the decrease of tars content in the gaseous product of biomass fast pyrolysis as well as to the increase in С1-С4 hydrocarbons, hydrogen and carbon monoxide (II) concentration.

This paper describes synthesis of Pd-containing catalysts of Suzuki cross-coupling based on amino-functionalized hypercrosslinked polystyrene. The investigation of the influence of a palladium concen-tration, solvent composition, temperature, type and concentration of base, and a type of a gas phase was carried out. It was shown that the catalyst developed allows achieving conversion of 4-bromoanisole higher than 98% for less than 1 h at mild reaction conditions and in the absence of a phase transfer agent. Catalyst reduction was found to result in formation of small Pd nanoparticles (about 3 nm in diameter) and a large number of Pd clusters, which are highly active in Suzuki-Miyaura cross-coupling (conversion of 4-bromoanisole reached 90.2% for 3 h). Copyright © 2015 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

The study is devoted to the low-temperature catalytic pyrolysis of biomass. The pyrolysis of peat was conducted using natural aluminosilicates and synthetic zeolites. It was found that the pore size of the mineral strongly affects the catalytic activity and provides the processing of the hydrocarbons forma-tion reactions. Bentonite clay was found to be the most effective catalyst for the biomass pyrolysis proc-ess. The use of bentonite clay as an addition to peat allows improving structural (strength, porosity) and sorption characteristics (sorption rate) of the molded compositions and can serve as a catalyst dur-ing its subsequent thermal conversion. The amount of gases obtained using natural aluminosilicate as a catalyst increased by 2 times compared to the non-catalytic process. The calorific value of the prod-ucts obtained was higher due to the light hydrocarbons formation. Copyright © 2015 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).