A synthetic method for betulin 3-O-propionate 28-O-acylates via the reaction of betulin 3-O-propionate with melts of benzoic, phthalic, cinnamic, and succinic acids at 185–195°C for 5–6 min was proposed.

Esters of betulin containing residues of bioactive aromatic and aliphatic acids are of interest to the chemical and pharmaceutical industry as hepatoprotectors, anti-inflammatory, antiulcer and immunomodulatory substances. The development of new efficient, ecological and economical methods for the synthesis of betulin esters is an actual task. A new "green" method for the production of betulin 3-acetate-28-maleate and betulin 3-acetate-28-levulinate has been developed. For the first time, esterification of betulin 3-acetate with melts of maleic acid and levulinic acids was carried out at a temperature of 185-200°C for 5-7 minutes to obtain betulin 3-acetate-28-maleate and betulin 3-acetate-28-levulinate, respectively. The structure of the resulting betulin esters was determined using IR and NMR spectroscopy, and the composition was determined by elemental analysis. The advantage of the developed method for the synthesis of 3-acetate-28-maleate and 3-acetate-28-levulinate of betulin in comparison with the known ones is: the synthesis is carried out in the absence of harmful and hazardous solvents (pyridine, methylene chloride, chloroform), a reduction in the duration of synthesis from 15-40 hours to 5-7 minutes. Maleic anhydride is used instead of maleic anhydride on the preparation of betulin 3-acetate-28-maleate.

For the first time, polysaccharides: cellulose and xylan, isolated from birch wood by peroxide delignification in "acetic acid- water" medium in the presence of catalyst (NH4)6Mo7O24, were proposed to be used to obtain polymer composites (films). The initial components: cellulose, xylan, sodium alginate were characterized using the methods of FTIR, GC, GPC, laser diffraction and chemical analysis.It is shown that the introduction of ultrasound- activated birch bark cellulose into the composition of xylanalginate composites leads to an increase in the strength of the films, an increase in their barrier properties with respect to water vapor, and also reduces the solubility of the films in water.

Synthetic methods for betulin 3-acetate-28-benzoate, betulin 3-acetate-28-p-bromobenzoate, betulin 3-acetate-28-cinnamate, betulin 3-acetate-28-succinate, and betulin 3-caetate-28-phthalate based on the reaction of betulin 3-acetate with fused benzoic, p-bromobenzoic, cinnamic, succinic, and phthalic acids at 185–195°C for 5–6 min are proposed for the first time.

The paper describes a one -step method for obtaining betulonic acid directly from birch bark, based on the use of the Jones reagent. The influence of the duration and liquid solid ratio (LSR) of the process on the yield of betulonic acid has been studied. By the method of mathematical optimization using full factorial experiment type 3(2) and the Statgraphics Centurion XVI software package, the optimal conditions were established to ensure the yield of betulonic acid of 15.9 wt.%: duration - 3.5 h, LSR - 15. The structure of betulonic acid obtained under optimal conditions was established by methods FTIR and NMR spectroscopy, composition - by elemental analysis.

Many natural polysaccharides have biological activity, which allows them to be used to obtain medicines. The development of new methods for the isolation of polysaccharides from plant materials, as well as the study of their properties and structure, is an actual task. In this work the polysaccharide galactoglucomannan (GGM) was isolated from pine wood time by the peroxide delignification in the “acetic acid-water” medium in the presence (NH4)6Mo7O24.Its yield was 10.1 wt.% from the weight of wood and 58.1 wt.% from the content of hemicelluloses in wood. By 13С NMR method it was found that the degree of GGM acetylation is 0.23 with substitution of carbon atoms of the pyranose ring at C2 and C3. According to the X-ray data, GGM has an amorphous supramolecular structure. The polysaccharide gluoxylan (GX) was isolated by alkaline extraction from the cellulose product obtained after peroxide delignification. Its yield was 4.3 wt.%. from wood and 24.5 wt.% from the content of hemicelluloses in wood.Glucoxylan does not contain acetyl groups (data from IR and NMR spectroscopy), it has a crystalline supramolecular structure and is poorly soluble in water. Composition and structure of the obtained polysaccharides were studied using chemical methods of analysis, IR spectroscopy, 1H, 13C, 2D HSQC NMR spectroscopy, gas chromatography, X-ray analysis.

For the first time, the process of extraction fractionation of "hemicelluloses-free" birch wood in an ethanol medium into cellulose product and ethanol lignin is studied and optimized. The composition and structure of cellulose product and ethanol lignin obtained by extraction fractionation of "hemicellulose-free" birch wood and other products of their subsequent transformations are characterized by methods of infra-red spectroscopy, nuclear magnetic resonance, X-ray diffractometry, scanning electron microscopy, BET surface area analysis, high-performance liquid chromatography, gel permeation chromatography, gas chromatography, and chemical and elemental analysis. The possibility of producing enterosorbents from birch ethanol lignin that are more effective than the commercial enterosorbents "Polyphepan" based on hydrolyzed lignin is established. A new approach to the biorefinery of birch wood into xylose, levulinic acid and enterosorbents is proposed based on the integration of an optimized process of extraction fractionation of "hemicellulose-free" birch wood in ethanol medium, alkaline isolation of xylan and its hydrolysis to xylose, cellulose product conversion into levulinic acid and ethanol lignin processing to enterosorbents.

For the first time, it is proposed to combine the environmentally friendly heterogeneous catalytic processes of wood hemicelluloses hydrolysis and peroxide delignification of «hemicellulose-free» wood for the biorefinery of birch wood into microcrystalline, microfibrillated, and nanocrystalline celluloses, xylose, and sorbents. The use of the solid acid catalyst ZrO2/SO42− for the hydrolysis of birch-wood hemicelluloses at a temperature of 150 °C makes it possible to obtain xylose with a yield of 72.5

For the first time, it was proposed to fractionate the main components of birch wood into microcrystalline cellulose, xylose and enterosorbents by integrating heterogeneous catalytic processes of acid hydrolysis and peroxide delignification of wood biomass. The hydrolysis of wood hemicelluloses into xylose is carried out at a temperature of 150 °C in the presence of a solid acid catalyst Amberlyst® 15. Then the lignocellulosic product undergoes peroxide delignification in a "formic acid – water" medium in the presence of a solid TiO2 catalyst to obtain microcrystalline cellulose (MCC) and soluble lignin. Under the determined optimal conditions (100 °С, Н2О2 – 7.2 wt.%, НСООН – 37.8 wt.%, LWR 15, time 4 h), the yield of MCC reaches 64.5 wt.% and of organosolvent lignin 11.5 wt% from the weight of prehydrolyzed wood. By the treatment of organosolvent lignin with a solution of 0.4% NaHCO3 or hot water the enterosorbents were obtained, whose sorption capacity for methylene blue (97.7 mg/g) and gelatin (236.7 mg/g) is significantly higher than that of the commercial enterosorbent Polyphepan (44 mg/g and 115 mg/g, respectively). The products of catalytic fractionation of birch wood are characterized by physicochemical (FTIR, XRD, SEM, GC) and chemical methods.

The kinetic regularities of the process of abies wood delignification in the "formic acid-hydrogen peroxide-water" medium at the presence of the MnSO4 catalyst at the temperature range 70-100 degrees C were established. It was determined that the delignification process is satisfactorily described by the first order equation. The reaction rate constants vary from 1.8 to 10.2.10(-4) min(-1), the activation energy is 85 kJ/mol. Mathematical optimization of the process of abies wood delignification, as a key stage of nanofibrillated cellulose production, was carried out by Box-Behnken statistical method. Under the optimal conditions: HCOOH 30 wt.%, H2O2-9 wt.%, LWR 15, temperature 100 degrees C, 4 h, the cellulose product with a lignin content of 1.2 wt.%, hemicelluloses 5.2 wt.%, cellulose 93, 1 wt% was obtained. The average hydrodynamic diameter of particles of nanofibrillated cellulose produced from abies wood by acid hydrolysis followed by ultrasonic treatment is 82 nm.

The possibility of isolation of high-quality cellulose by peroxide delignification of birch wood in an acetic acid-water medium in the presence of a TiO2 catalyst at a temperature of 100 °C was shown. The influence of the process conditions (concentration of hydrogen peroxide and acetic acid, liquid/wood ratio (LWR)) on the yield and composition of cellulose products was established. Numerical optimization of the process was carried out using a full factorial experiment. The optimal conditions for isolation from birch wood a cellulose product with residual lignin content of ≤ 1 wt.% are: СН3СООН concentration 23.8 wt.%, Н2О2 concentration 4.9 wt.%, LWR14.9, temperature 100 °C, time 4 h. Under these optimal conditions, the yield of a cellulose product with a cellulose content of 92.5 wt.% was 49.9 wt.%

Experimental and mathematical methods were used to obtain the optimal parameters of peroxide delignification of larch in the presence of MnSO4 catalyst, which provide a high yield of cellulose (44.3 wt.%) with a low content of residual lignin: temperature 100 °C, content of H2O2 6 wt.%, CH3COOH 25 wt.%, hydromodulus 15, and duration 3 h. The cellulose produced under optimal conditions had the following chemical composition: cellulose 92.7 wt.%, lignin 0.6 wt.%, and hemicellulose 5.7 wt.%. IR spectroscopy and XRD studies revealed that the structure of cellulose produced from larch is similar to that of industrial microcrystalline cellulose. The proposed catalytic method allows obtaining larch-derived cellulose with a minimum content of lignin under mild conditions in a single step with a high yield, crystallinity 0.8 and crystallite size 3.0 nm.

Two alternative routes of softwood catalytic oxidative fractionation to cellulose products and fine chemicals are assessed. We suggested to use the process of larch wood peroxide oxidation in the medium acetic acid - water at temperatures 70-100 degrees C in the presence of soluble catalyst (NH4)(6)Mo7O24 to produce microcrystalline cellulose (35.0 wt% on wood), microfibrillated cellulose (7.5 wt% on wood) or nanocrystalline cellulose (3.7 wt% on wood) and low molecular weight organic compounds (20 wt% on wood). The developed process reduces the number of technological stages and increase an environmentally safety of nanocelluloses production from wood, compared to traditional technologies. Another suggested process of softwood (pine and larch) fractionation to vanillin (up to 4.7 wt% on wood) and cellulose (up to 34.6 wt% on wood) is based on wood oxidation by oxygen in water-alkaline medium at temperatures 160-180 degrees C in the presence of suspended catalyst Cu(OH)(2). The further acid conversion of cellulose by 2 % H(2)SO(4)at 180 degrees C produces levulinic acid with the yield up to 9.7 wt % on wood. The integration of the processes of dihydroquercetin and arabinogalactan extraction isolation from larch wood, oxidation of extracted wood by oxygen to vanillin and cellulose in the presence of catalyst Cu(OH)(2), acid catalyzed conversion of cellulose to levulinic acid and arabinogalactan hydrolysis over solid acid catalyst to arabinose and galactose leads to an increase in the number of target products. FTIR, XRD, SEM, AFM, solid state C-13 CP/MAS and chemical methods were used for characterization of cellulose products. Organic compounds were identified by GC, HPLC and GC-MS methods. The two alternative schemes of larch wood catalytic oxidative biorefinery to produce nanocelluloses and fine chemicals have been developed.

In the present work, a kinetic study and optimization of the process of spruce wood peroxide oxidation in “acetic acid–water” medium in the presence of suspended TiO 2 catalyst at temperatures 70–100 °C were accomplished for the first time. The effect of wood species and organic solvent nature on the features of the processes of catalytic peroxide fractionation of wood biomass on microcrystalline cellulose and soluble organic products from lignin and hemicelluloses is described. Solid products of wood peroxide oxidation were characterized by FTIR, XRD, SEM, solid state 13 C CP-MAS NMR and soluble products were identified by GC–MS. The experimental optimization of the process of birch wood oxidation by oxygen in “water–alkaline” medium in the presence of suspended Cu(OH) 2 catalyst was carried out at temperature range 160–180 °C. The scheme of biorefinery of birch wood, based on catalytic oxidative fractionation of wood biomass with the production of pentosans, vanillin, syringaldehyde and levulinic acid was developed. The resulting products are in demand in many areas, including food, pharmaceutical, chemical, cosmetic industries, synthesis of new functional and biodegradable polymers.

Pyrolysis of Kaa-Khemsky and Mezhegeisky coals was investigated with an increase in temperature to 900 °С with a change in pressure in the reactor by increasing the retention time of volatile substances in the pyrolysis zone at 600 °С and 640 °С. Liquid products of coal pyrolysis were extracted by hexane and benzene. The composition of liquid extracts was studied by chemical analysis, GC-MS and IR-spectroscopy, the solid product of extraction-by elemental analysis and scanning electron microscopy. It was established, that coal nature and pyrolysis conditions affect significantly on the yield of liquid, solid and gaseous products. Also, the retention time of volatile substances in pyrolysis zone influences on the yield of solid product (increases from 60 %wt to 73 % wt) and on composition of hexane and benzene soluble tar fractions. This is also facilitated by an increase in pressure in the reactor as a result of the release of volatile substances from coal in the pyrolysis zone

The experimental and mathematical optimization of abies wood peroxide delignification process in the formic acid – water medium in the presence of TiO₂ catalyst was carried out. It was established that in the temperature range 70-100 °С the rate constants of the delignification process vary between 0.4 and 3.2 · 10-4 min-1. The optimal parameters for the production of cellulose product with a residual lignin content of ≤ 3 wt.% were determined (temperature 100 °С, concentration Н₂О₂ 10 wt.%, НCOOН 38 wt.%, LWR 15, time 4 h). The features of abies wood peroxide delignification processes in the presence of TiO₂ catalyst in “ formic acid – water” and “acetic acid – water” were compared. It was shown the possibility of abies wood fractionation in the medium “ formic acid-water” to high-quality cellulose with the yield of 94 wt.% (the content of residual lignin 2.3 wt.%) and to low molecular weight lignin with the yield of 21 wt.% (average molecular weight 1854 g/mol and polydispersity 1.65). The obtained chemically active lignin can be used for the production such valuable products as enterosorbents, nanoporous carbon materials, aerogels

A new method to obtain cellulose sulfates from available and inexpensive raw material—aspen wood was developed. This method integrates catalytic peroxide delignification and sulfamic acid sulfation stages. Solvents such as acetic acid and water were used for isolation of pure cellulose by wood peroxide delignification with TiO 2 catalyst. Low-aggressive and less-toxic sulfating agent—sulfamic acid–urea mixture was used to obtain cellulose sulfates.

The conventional way of producing microcrystalline cellulose (MCC) from wood raw materials is multistage; it is based on integrating the environmentally hazardous processes of pulping and bleaching of cellulose and the acid hydrolysis of the amorphous phase of cellulose. This work describes an improved single-stage catalytic method for the production of MCC from softwood and hardwood that is based on the peroxide delignification of wood in an acetic acid–water medium under mild conditions (100°C, atmospheric pressure) in the presence of an environmentally safe TiO2 solid catalyst. The processes of MCC production via the peroxide catalytic delignification of various wood species are optimized experimentally and mathematically. The following optimum modes for the production of MCC with a yield of 36.3–42.0 wt % of absolutely dry wood, a residual lignin content of ≤1.0 wt %, and a hemicellulose content of ≤ 6.0 wt % are determined: For aspen: 5 wt % H2O2, 25 wt % CH3COOH, and a liquid/wood ratio of 10. For birch: 5 wt % H2O2, 25 wt % CH3COOH, and a liquid/wood ratio of 15. For silver fir: 6 wt % H2O2, 30 wt % CH3COOH, and a liquid/wood ratio of 15. For larch: 6 wt % H2O2, 30 wt % CH3COOH, and a liquid/wood ratio of 15.