Anton L. Esipovich

This study is related to producing a set of fatty acid esters from different vegetable oils and C1–C12 alcohols. A total of 66 products were synthesized. The obtained esters were characterized by fatty acid composition, density, viscosity, saponification value, acid value, iodine value, low-temperature properties, and oxidative stability. It was established that the fatty acid composition, as well as alcohol, used has a significant impact on esters properties. Comparing physicochemical properties of fatty acid esters with existing standards and specifications, it was proposed to use esters for different industrial applications. In particular, rapeseed oil fatty acid methyl esters are an ideal candidate for application as biodiesel, while transesterification of soybean oil, sunflower oil, rapeseed oil, and coconut oil with higher alcohols led to products with promising properties as bio-lubricants. Castor oil alkyl esters could potentially be utilized as base oils due to their excellent viscosity and low-temperature properties.

Background. Ozonation products of unsaturated fatty acids in fats and oils – 1,2,4-trioxolanes – which contribute to the normalization of oxidative and energy metabolism in various diseases, may be a promising substance for the creation of new combined anti-burn drugs.The aim. To study the effect of 1,2,4-trioxolanes in a pharmaceutical composition with betulin, which exhibits wound-healing properties, on indicators of oxidative stress and on energy metabolism in the treatment of burns in an experiment onrats. Methods. The experiments were carried out on 50 male Wistar rats with seconddegree skin burns. We assessed the activity of glutathione reductase, glucose-6-phosphate dehydrogenase, lactate dehydrogenase, aldehyde dehydrogenase, superoxide dismutase and catalase, as well as the level of lipid peroxidation indicators.Results. The properties of 1,2,4-trioxolanes were studied and a pharmaceutical composition of 1,2,4-trioxolanes with betulin from birch bark in fish oil was developed. The effect of this composition on oxidative and energy metabolism in rats during the treatment of burns was studied. The activation of NADP/H and NAD/H dependent enzymes (glutathione reductase, glucose-6-phosphate dehydrogenase, lactate dehydrogenase, aldehyde dehydrogenase), as well as superoxide dismutase and catalase, and the normalization of lipid peroxidation parameters under the influence of the studied composition in the treatment of burns were revealed. The effect of the composition on the energy metabolism of erythrocytes was noted, which was assessed by changes in the ratio of lactate dehydrogenase activity in the reverse and direct reactions. Morphohistological studies showed that using the composition under normal conditions and in case of a burn had no effect on the structure of the stomach wall, and also improved the condition of the burn wound on the day 10 compared to the wound condition in animals without treatment.Conclusion. The proposed composition of 1,2,4-trioxolanes and betulin in fish oil, which allows normalizing oxidative and energy metabolism and improving the condition of a burn wound without toxic effects on the stomach wall, can be used as an element of additional therapy in the treatment of burns.

Copper (I, II) oxide powders were tested for glycerol conversion to lactic acid under alkaline conditions. Fresh and spent catalysts were characterized using powder X-ray diffraction, Scanning Electron Microscopy/Energy Dispersive X-ray Spectroscopy, the BET-nitrogen adsorption method and FTIR spectroscopy. In all cases, an almost complete in situ reduction of Cu (I, II) oxides into metallic Cu was observed, even after one catalytic run. Moreover, all the samples of spent catalysts showed similar catalytic activity regardless of their initial form and particle size. Commercial copper powders, prepared copper powders and in situ reduced copper catalysts were tested under the same conditions to compare their catalytic activity. It was shown that the in situ reduced copper catalyst had similar activity to the specially prepared copper powders and much higher activity compared to the commercial copper powders. The in situ reduced copper catalyst exhibited rather high stability. The glycerol conversion and lactic acid selectivity were about 98% and 70%, respectively, after ten catalytic cycles.

Introduction. Lipid metabolism disorders, caused by both excessive physical and psycho-emotional stress, and physical hypoxia, are important problems in the prevention and treatment of a number of diseases.The objective was to study the effect of 1,2,4-trioxolanes and betulin in fish oil on lipid and energy metabolism in an experiment on rats under hypoxia and immobilization stress (IS).Methods and materials. The studies were carried out using 75 male Wistar rats (intact and experimental animals) on a model of hypoxia and immobilization stress for 10 days. The treatment was carried out with the composition of betulin (0.1 %), 1,2,4-trioxolanes (10 %) in fish oil.Results. Under stress, regardless the type of stress, in groups without treatment, there was a significant disturbance in lipid metabolism, which was reflected in the following indicators: total cholesterol increases by 5–8 %, TG increase by 5 times, HDL increase by 10 %, VLDL and LDL increase by ~ 6 times. It was revealed that the composition of fish oil, botulin and 1,2,4-trioxolanes, previously obtained by ozonation of lipids, had a normalizing effect on the indexes of lipid and energy metabolism under hypoxia and IS in rats.Conclusions. 1,2,4-trioxolanes with betulin in fish oil may be useful for population groups with physical inactivity (students, office workers, elderly people, disabled people), as well as for athletes with excessive physical activity.

The MIL-100(Cr), PW12@MIL-100(Cr) and PW4@MIL-100(Cr) catalysts were prepared and characterized through XRD, FTIR, BET, SEM, EDS and Raman spectroscopy. A comparison of the catalytic properties of the synthesized materials in the epoxidation of FAMEs with hydrogen peroxide was made. The PW4@MIL-100(Cr) catalyst exhibited the highest catalytic activity and provided a high selectivity for the formation of epoxides. The effects of the reaction temperature, catalyst loading, reaction time and FAME:hydrogen peroxide molar ratio on the reaction performance were investigated, and the optimal process conditions were determined. An epoxide yield of 73% with a selectivity of 77% could be obtained using PW4@MIL-100(Cr) after 4 h at 40 °C. The catalytic stability test showed that PW4@MIL-100(Cr) could be easily separated and reused without any treatment for at least five consecutive cycles without a loss of activity or selectivity.

Green chemistry provides a broad range of possibilities for researchers to design products and processes that minimise or eliminate the use and generation of hazardous substances in chemical engineering. The use of renewable feedstocks coupled with catalysis is one of the key principles of green chemistry. In this regard, non-edible vegetable oils and fatty acid methyl esters (biodiesel) produced by the transesterification of vegetable oils have a great potential in the chemical industry. Their catalytic conversion allows them to produce a wide range of useful chemicals. At the same time, the use of fatty acid methyl esters has advantages and they are more preferable as compared to vegetable oils due to fewer impurities, lower viscosity, etc. The production of biodiesel is associated with the formation of another important and versatile chemical, glycerol, which is currently produced in the world only through the transesterification of vegetable oils. This critical review highlights the recent achievements in the green and sustainable production of various chemicals from fatty acid methyl esters, including oxidation, amidation, hydrogenation, deoxygenation, ethoxylation, metathesis, and isomerisation reactions. A special focus is given to the applicability of each method in industry. We suppose that this comprehensive review will provide insight into the most significant ways to convert fatty esters into valuable products since they are “rough diamonds” and have a great future in the chemical industry.

Mechanism analysis and kinetic modeling of glycerol conversion into lactic acid in the alkaline media with and without heterogeneous catalyst Cu NPs are reported. The reaction pathways were determined in agreement with the experimental results and comprise several types of reactions, namely dehydrogenation, hydrogenolysis, dehydration and C–C cleavage. Experimental concentration-time profiles were obtained in a slurry batch reactor at different glycerol, NaOH and Cu NPs concentrations in a temperature range of 483–518 K. Power law, Langmuir–Hinshelwood (LH) and Eley–Rideal (ER) models were chosen to fit the experimental data. The proposed reaction pathways and obtained kinetic model adequately describe the experimental data. The reaction over Cu NPs catalyst in the presence of NaOH proceeds with a significantly lower activation barrier (E_a = 81.4 kJ∙mol⁻¹) compared with the only homogeneous catalytic conversion (E_a = 104.0 kJ∙mol⁻¹). The activation energy for glycerol hydrogenolysis into 1,2-propanediol on the catalyst surface without adding hydrogen is estimated of 102.0 kJ∙mol⁻¹. The model parameters obtained in this study would be used to scale an industrial unit in a reactor modeling.