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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.

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.

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.

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.

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.

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).

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.