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A comparison of IR spectra and molecular weight distribution of arabinogalactan sulfates as sodium and ammonium salts obtained using various sulfating reagents was performed. According to the data, sulfated derivatives of arabinogalactan differ from each other in the nature of hydrogen bonds and molecular weight distribution. Using coagulological tests during activation of coagulation of platelet-poor human plasma in vitro, the anticoagulant properties of sulfated arabinogalactan derivatives in various salt forms differing in the preparation method, sulfation degree, and molecular weight were studied. It was found that the sample in the form of the sodium salt of sulfated arabinogalactan (SAG 1) with a sulfur content of 13.2 wt % and a polydispersity degree of 1.52 exhibited twofold greater anticoagulant activity than the sample in the form of the ammonium salt of sulfated arabinogalactan (SAG 2) with a sulfur content of 6.6 wt % and a polydispersity degree of 1.30. The antithrombin (aIIa) activity of the samples obtained by sulfation with a complex of pyridine and sulfuric anhydride (SAG 1) and a complex of sulfamic acid (SAG 2) was 23.42 ± 1.86 and 10.20 ± 1.50 U/mg, respectively; the value of the antifactor Xa activity of SAG 1 and SAG 2 was 2.13 ± 0.42 and 0.37 ± 0.08 U/mg; the aIIa/aXa ratio for SAG 1 and SAG 2 was 11 and 28, respectively. The antifactor Xa (aXa) activity of SAG, which is lower than that of unfractionated heparin (UFH), and a high aIIa/aXa activity ratio may contribute to less provocation of bleeding by SAG samples compared to UFH.

The method of preparation of organo-mineral fertilizer with increased resistance to mineral components leaching by water, based on the impregnation of support from abies bark by water solution of potassium nitrate, zinc, copper and magnesium sulphates, was proposed. The dates about composition and properties of the porous support from abies bark were provided. The potassium nitrate contents (23.5 mass.%) and concentration of nitric acid solution (0.1 N) providing high water resistance of fertilizer were determined. I t was shown, that application of treatment by 0,1 N nitric acid allows reduce delete from fertilizer by water nitrogen in 2.4 times, and other mineral components – in 1.7–1.9 times. The ability of fertilizer to slow release of mineral components by water during long time was identified, that determined effect of his prolonged action. It was shown, that after treatment fertilizer by water at room temperature during 30 days from him leaching 64.8% potassium, 66.6% nitrogen, 70.3% magnesium, 65.2% copper и 65.3% zinc from their initial contents. The growth-stimulating effect of organo-mineral fertilizer based on the abies bark was shown by experiments on germination of wheat seed variety "Novosibirskaya 15".

Methods have been developed for the preparation of enterosorbents by treating crushed abies bark with the 1.5% aqueous of NaOH solution or by extraction with hexane. It was found that all obtained enterosorbents have good sorption properties with respect to gelatin and methylene blue. The highest sorption activity for methylene blue was shown by a sample, obtained by extraction of abies bark with hexane (97.0 mg/g), and for gelatin sorption activity – a sample, obtained by treatment of abies bark with alkali (225.0 mg/g). It was found that the enterosorbent, obtained by treatment of abies bark with alkali solution both at a dose of 0.15 g per kg of animal weight (g/kg) and at a dose of 0.20 g/kg and the enterosorbent, obtained by extraction of abies bark with hexane at a dose of 0.20 g/kg, have the highest efficiency for the treatment and prevention of acute experimental Escherichiosis. From the considered methods of obtaining enterosorbents from abies bark for the treatment and prevention of gastrointestinal infections of animals, it is recomended to use a method based on treatment of abies bark with alkalai solution and apply the drug in a dose of 0.15 g/kg

The organic xerogels, prepared from tannins and ethanol lignins of the fir (Abies sibirica), were synthesized for the first time. The influence of the composition of initial mixture and pH on the characteristics of xerogels obtained by sol-gel condensation of formaldehyde with polyphenols of fir has been studied. The possibility of regulating the density and porosity of gels by varying of the concentration of ethanol lignin in the initial mixture was established. It was found that tannin-lignin-formaldehyde gel with low-density (0.11 g/cm3), and very high porosity (92%) is formed at a mass ratio tannins and lignins equal to 1. According to FTIR data, the process of xerogel formation is carried out by cross-linking due to the formation of carbon-carbon and alkyl ethers bonds. SEM method confirmed the formation of branched macromolecular structure of gels from interconnected spherical particles of different sizes. Thermogravimetric analysis demonstrates greater thermal stability of tannin-formaldehyde gels compared with the tannin-lignin-formaldehyde gels. The increase of lignin concentration in gels more than 50–65% (by the mass) reduced the temperature of their intensive mass loss on 23–63 °С. The obtained organic gels are non-flammable polymers, and they can be used as thermal and fire retardant materials.

Method is suggested for obtaining biochar materials by treatment of a finely dispersed (≤0.1 mm) bark of aspen and(or) larch with a 40% formaldehyde solution and subsequent thermal activation of the activated bark. It was found that keeping the composite at a temperature of 50–80°C for three days makes the binding process complete. Further carbonization at temperatures of 350–900°C yields a biochar with bulk structure. The method of IR spectroscopy confirmed that the functional composition of bark changes under the action of a cross-linking agent and — CH2 — bonds are additionally formed. It was found that the larch bark containing lignins of predominantly G-type and condensed tannins is more suitable for obtaining porous biochar materials (with specific surface area of 94–161 m2 g−1) as compared with the aspen bark. The adsorption properties of biochar materials produced from the modified bark in removal of Cu(II) ions from aqueous solutions. It was found that, on being carbonized at 900°C, a sample of modified aspen bark can extract 122.9 to 220 mg g−1 of copper compounds on raising the sorption temperature from 25 to 45°C.

The ability of producing of effective carbon sorbents from abies bark with the use of thermal alkaline activation in presence of potassium hydroxide was shown. The effects of ratio of bark to alkalin, and temperature of bark pre-carbonization on the porous structure and sorption properties of the carbon sorbents were studied. It was shown , that the capacity of carbon sorbents on iodine is defined by pores with a width 0,73 – 1,86 nm, on methylene blue - 0,86 – 2,95 nm, and on vitamin B 12 - ≥ 9,31 nm. It was determined, that the carbon sorbent, producing by alkaline activation of product of abies bark carbonization at 400 о С , has a high sorption capacity for studied marker substances. For this sorbent kinetic of iodine, methylene blue and vitamin B 12 sorption was studied in comparison with the simple of commercial active coal for medical purposes. It was determined, that this sorbent exceeds the commercial sample in sorption of iodine and vitamin B 12 in 1,5 time, and at sorption of methylene blue – in 1.7 time, and it is characterized by a higher rate constants of their markers sorption.

Thermogravimetric (TG/DTG) methods have been used to study the thermal destruction of fir and aspen ethanol lignins at different heating rates in an inert (argon) medium. For each of the lignins, the main stages of thermal degradation were found under conditions of programmed heating of samples from 298 to 1173 K at heating rates of 5, 10, and 20 K/min. It was found that with an increase in the heating rate, the ranges of the main degradation of lignins expand. Shifts toward higher temperatures were 13.8 K for fir lignin and 21.1 K for aspen lignin. At the same temperatures, ethanol lignin from aspen showed a greater weight loss than fir lignin. Using the Ozawa–Flynn–Wall, Broido, and Redfern–Coats kinetic models, the results of the thermogravimetric analysis of the studied lignins are analyzed and the values ​​of the activation energy are calculated. The most reliable values of ​​the activation energy were obtained by the Ozawa–Flynn–Wall isoconversion method for the main temperature range of degradation (from ~569 to ~725 K): 113 kJ/mol for fir ethanol lignin and 106 kJ/mol for aspen ethanol lignin.

Porous materials prepared from brown and black coals were used as sorbents for the extraction of chromium(VI) from aqueous solutions. They were compared with an AG-3 commercial sorbent. The effect of the acidity of reaction medium on the adsorption of chromium(VI) was established. The extraction of Cr(VI) from aqueous solutions reached a maximum in a range of pH 1.5–2.0. A kinetic study made it possible to determine equilibration times in the porous material–chromium(VI) solution systems.

The effect of the conditions of the acetylation process of raw and activated birch bark on the yield and composition of the products is investigated. The structure of biologically active betulin diacetate (BDA) is confirmed with physicochemical methods. The optimal regimes of the one-step original method for the production of BDA from raw and activated birch bark are established using the experimental and computational techniques.

Traditional processes of acid-catalyzed hydrolysis of wood are ineffective due to the low quality of formed glucose solutions contaminated with impurities that inhibit fermentation of glucose to ethanol. This problem grows during the hydrolysis of birch wood containing large amounts of hemicellulose. This work proposes producing quality glucose solutions using sulfuric acid (H2SO4, 80%) catalyzed hydrolysis at 25°C the cellulosic products formed during the catalytic peroxide delignification of birch wood. It is established that the composition of cellulosic products strongly affects the contents of glucose, xylose, and impurities inhibiting the enzymatic synthesis of bioethanol: furfural, 5-hydroxymethyl furfural, and levulinic acid. High yields (80.4–83.5 wt %) of glucose are achieved using cellulosic products produced by integrating the processes of sulfuric acid hydrolysis of hemicelluloses from birch wood and peroxide delignification of prehydrolyzed wood in the presence of catalysts: 2% H2SO4 and 1% TiO2. Concentration of inhibitors of enzymatic processes in these hydrolyzates is below the allowable limits. Hydrolyzates with maximum glucose content (86.4–88.5 wt %) and minimum concentration of inhibiting impurities produced by acid hydrolysis of cellulosic products treated with an 18% solution of NaOH. Gas chromatography, HPLC, and chromato-mass spectrometry are used to analyze the composition of hydrolyzates. Cellulosic products are examined by SEM, XRD, and chemical analysis.

The traditional processes of catalytic acid hydrolysis of wood are low effective due to the low quality of the formed glucose solutions contaminated with admixtures that inhibit fermentation of glucose to ethanol. This is a particularly acute problem in hydrolysis of birchwood containing hemicelluloses in large proportions. In the present paper, quality glucose solutions are suggested to produce via sulfuric acid hydrolysis (80 % H 2 SO 4 , 25 °C) of cellulose products formed during catalytic peroxide delignification of birchwood. The composition of the cellulose products are established to affect considerably the content of glucose, xylose and admixtures (furfural, 5-hydroxymethylfurfural, levulinic acid) in glucose, which inhibit enzymatic synthesis of bioethanol. High yields of glucose (80.4–83.5 wt %) are achieved with cellulose products prepared by integrated processes of sulfuric acid hydrolysis of birchwood hemicelluloses and peroxide delignification of pre-hydrolyzed wood in the presence of catalysts 2 % H 2 SO 4 and 1 % TiO 2 . Concentrations of inhibitors of enzymatic processes are lower of the admissible levels in these hydrolyzates. The hydrolyzates with the maximal glucose content (86.4–88.5 wt %) and minimal concentration of inhibiting impurities are prepared by acid hydrolysis of cellulose products treated with 18 % NaOH. The hydrolyzate composition was studied using gas chromatography, HELC, chromatomass spectroscopy. IRS, XPS and chemical techniques were used for characterization of cellulose products.

Carbonization of betulin (betulinol) as an individual carbon precursor was studied in the temperature range of 400–800°C in the presence of KOH. Differential thermal analysis and IR spectroscopy were used to determine the influence of KOH on major structural changes and the chemical composition of betulin, which occur at 400–500°C. It was shown by scanning electron microscopy and BET analysis that KOH promoted the formation of a developed specific surface (SBET 1350–2100 m2/g) at temperatures of 600–800°C and had the greatest influence on the textural and adsorption properties of the resulting porous carbon adsorbents. It has been found that the formation of microporous carbon materials with a pore size of 1.92 nm and a specific micropore surface area of 1275 m2/g is possible upon the activation of betulin with KOH at 800°C. Betulin may be proposed to control the porosity of the carbon carriers derived from birch wood.

Highly porous materials containing zinc oxide were prepared form modified pine wood. The growth dynamics of zinc oxide microcrystallites in the course of carbonization of pine sawdust mixed with ZnCl2 was studied. The hexagonal wurtzite-type ZnO phase is formed at 400°С and is broken down at approximately 800°С. The synthesized composite material has a high specific surface area, up to 1900 m2 g–1. The relationships of the porous structure formation in the composite in relation to the temperature and subsequent treatment with water were revealed. Opening of the porous structure of the composite in the course of carbonization of modified pine sawdust is associated with the formation of crystal-like phases of carbon and ZnO.

Текст статьи не публикуется в открытом доступе в соответствии с политикой журнала. It was established that the main factors responsible for the yield and specific surface area of porous carbon materials obtained by the chemical activation of the wood of birch are the nature of a modifying agent and the temperature of pyrolysis. The additional opening of the porous structure of the product of the chem ical activation of wood occurs at the stage of its water treatment as a result of the removal of water soluble compounds. The conditions of the carbonization of birch wood modified with H3PO4, KOH, and ZnCl2 were chosen in order to provide the significant development of the porous structure of carbon materials. The porous carbon material with the highest specific surface area (more than 2560 m2/g) was obtained by the water washing of the product of the carbonization of birch wood modified H3PO4 at 400°C.

Текст статьи не публикуется в открытом доступе в соответствии с политикой журнала. The effect of the conditions of consecutive carbonization–activation of the bark of larch, fir tree, and birch in a fluidized bed reactor on the yield, textural characteristics, and sorption properties of the result ing porous carbon materials was studied. The rate of temperature increase at the stage of the pyrolysis of bark exerted the greatest effect on the specific surface area, total pore volume, and sorption capacity of porous car bon materials for iodine and methylene blue. The porous carbon materials obtained by the slow pyrolysis (5 K/min) of larch bark with an isothermal exposure for 60 min at 600°C and the subsequent activation with CO2 at 850°C for 30 min were characterized by a maximum sorption activity. The porous carbon materials obtained from bark by consecutive carbonization–activation in a fluidized bed were similar to commercial powder sorbents from wood in their characteristics.

The effects of sulfated ZrO2 and ZrO2-Al2O3 catalysts and acidic zeolite catalysts with various Si/Al ratios on the thermal conversion of alkali lignin in supercritical ethanol at 300–400°C and on the composition of the resulting products have been investigated. All of the catalysts enhance lignin conversion into liquid products. The strongest effect with the catalysts based on sulfated ZrO2 is attained at 400°C; with the zeolites, at 350°C. The catalysts diminish the concentration of phenol and its derivatives and increase the concentration of ethers (mainly the 1,1-diethoxyethane concentration) in the liquid products. The zeolite catalysts are preferable, since the reaction over the ZrO2-containing catalysts produces gaseous compounds in higher yields. The maximum lignin conversion and a high yield of low-boiling liquid products are achieved at 350°C with the zeolite catalyst with Si/Al = 30, which contains a high concentration of acid sites that are stable at elevated temperatures. The most abundant phenolic liquid products of lignin conversion over the zeolite catalysts at 350°C are methoxyphenols and their methylated and ethylated derivatives.

Certain fundamental aspects of how the porous structure is formed in carbon materials produced by pyrolysis of microcrystalline cellulose modified with phosphoric acid, potassium hydroxide, and zinc chloride were determined. The above chemical promoters shift the onset of the process of intense thermal transformation of cellulose to lower temperatures and promote formation of porous carbon materials. Water treatment of porous carbon materials produced by pyrolysis of microcrystalline cellulose with high content of a promoter leads to additional pore opening due to the removal of the excess amount of the promoter and soluble products formed in its interaction with cellulose, which makes it possible to obtain porous carbon materials with specific surface area of up to 1500 m2 g−1.

It is established that the main regularities of the peroxide delignification of aspen wood in the temperature range of 70–100°С in the presence of dissolved (H2SO4) and solid (TiO2) catalysts are similar. With an increase of the temperature, the concentration of hydrogen peroxide and acetic acid, and the hydromodule (HM) values, as well as the duration of the process and the content of cellulose in the cellulose products, increase, while the content of the residual lignin decreases. Simultaneously, the total yield of cellulose products decreases independently of the nature of the catalyst. Delignification processes are satisfactory described by the first-order equation. A sufficiently high activation energy (88 kJ/mol in the presence of H2SO4 and 75 kJ/mol in the presence of TiO2) indicates the absence of significant external diffusion constraints in the selected conditions. The optimal conditions of obtaining cellulose products with a low content of residual lignin from aspen wood are found by the calculation methods. It is shown by Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), and scanning electron microscopy (SEM) that the structure of cellulose products obtained corresponds to the structure of industrial microcrystalline cellulose. In the optimal conditions, a high-quality cellulose product can be obtained in mild conditions (the temperature is 100°С, atmospheric pressure) by using a safer and technological TiO2 catalyst instead of a sulfuric acid catalyst.

Study of the carbonization of birch wood demonstrated that, under conditions of a preliminary carbonization at a temperature of 400°C, KOH favors better, compared with NaOH, development of the specific surface area (S BET ≈ 2000 m2 g−1) and microporous volume (0.6 cm3 g−1). The resulting porous carbon materials possess improved adsorption properties and are effective in separation of He(H2)-CH4 mixtures.

Formation of the porous structure of carbon material obtained by carbonization of microcrystalline cellulose (MCC) in the presence of modifying additives KOH and H3PO4 has been investigated. The optimal conditions for the synthesis of porous carbon materials (PCMs) from chemically activated MCC have been revealed. The highest specific surface area (about 1500 m2/g) is observed for water-washed carbon products obtained by carbonization at 800°C of MCC containing 50 wt % KOH and by carbonization at 400°C of MCC with the addition of 50 wt % H3PO4.

The pore-structure characteristics of active carbons prepared by the thermolysis (800°C) of brown coal impregnated with potassium hydroxide were studied. The dependence of the specific surface area, total pore volume, micropore volume, micropore fraction, and micropore size distribution on the KOH/coal weight ratio R KOH ≤ 1.0 g/g was found. Condensation processes with the formation of a low-porosity material were predominant at low ratios of R KOH ≤ 0.1 g/g. The development of a micropore structure was observed at R KOH ≥ 0.1 g/g, and it increased as R KOH was increased to 1.0 g/g. It was hypothesized that pore formation was due to the thermally initiated reactions of the structural fragments of coal with KOH molecules, which occurred within the framework of coal.

Carbonization of birch sawdust modified with zinc chloride and selected properties of the resulting porous carbon materials were studied.

Intercalation compounds of GT-1 and GAK-3 graphites were electrically synthesized in concentrated sulfuric and nitric acids. Porous composite samples based on thermally expanded graphite produced from electrochemically synthesized GT-1 graphite hydrosulfate, chemically synthesized GSM-1 graphite nitrate, and fluoroplastic-4D (1–15 wt %), with a volume density of 650–1090 g l−2, were fabricated and studied.

The influence of chemical modification and thermal activation on the porous structure of Donbass anthracites (Ukraine) and on the state and catalytic properties of supported palladium has been studied. The most regular distribution of supported palladium particles with an average size of about 2 nm was observed for the supports prepared from the chemically modified anthracites. The activity of supported palladium in the liquid-phase hydrogenation of cyclohexene varies more than 10-fold depending on the preparation method of the anthracite support. The catalysts with the palladium nanoparticles located in micropores of the carbon support exhibit a lower catalytic activity.

Surface nano-size structures have been obtained by supporting on oxide supports (SiO 2 , MgO, Al 2 O 3 ) some cluster carbonyls of Os, Fe, Fe-Rh and by their following thermal conversions. Surface species were characterized by IR-spectroscopy, high-resolution TEM, XPS, Mossbauer spectroscopy and temperature-programmed desorption technique. Their catalytic properties was studied in CO hydrogenation reaction.

Chemical transformations of SiO2-supported [Fe5RhC(CO)16]− and [Fe4RhC(CO)14]− clusters in Ar, CO, and synthesis gas are studied by IR spectroscopy, Mossbauer spectroscopy, and transmission electron microscopy. It is shown that partial transformation of the [Fe5RhC(CO)16]− cluster to the [Fe4RhC(CO)14]− cluster occurs immediately after its deposition on the substrate surface with the simultaneous formation of Fe2+ ions. The complete conversion of the supported [Fe5RhC(CO)16]− cluster to [Fe4RhC(CO)14]− is observed at 323 K in the synthesis gas. At 373 to 423 K [Fe5RhC(CO)16]− transforms into a mixture of Fe4Rh2C(CO)16, [Fe4RhC(CO)14]−, and [Fe53Rh3C(CO)15]− clusters. In the 523 to 623 K range, the supported [Fe5RhC(CO)16]− cluster decarbonylates completely to form bimetallic species A 5 A in size. Silica-supported FeRh clusters are active in propylene hydroformylation at 423 to 473 K and form a mixture of butyl alcohols and butyraldehydes.

C3H6 hydroformylation and CH3OH synthesis on organometallics derived (Pd + Ln)/ SiO2 and Pd/SiO2 catalysts have been studied. The activity and selectivity towards methanol in CO + H2 reaction were observed to increase for all the modified catalysts while both the hydroformylation activity and selectivity towards oxygenates in C3H6 hydroformylation decreased for the catalysts in comparison to those of Pd/SiO2. The FTIR, TPD data and characteristic catalytic properties of the catalysts studied allow to suggest that C3H6 hydroformylation on (Pd + Ln)/SiO2 catalysts occurs on monometallic Pd clusters without participation of mixed active sites and CO complexes activated thereon.

A lack of high-quality carbon adsorbents (CA) with a uniform microporous structure is the main impediment to the development of new and the improvement of existing adsorption methods for purifying and separating gases. The sorbent structure, i.e., the size, volume, and ratio of principal pore types, is determined by the nature of the precursor and its processing into activated carbon. As a rule, the porosity of carbonized carbons from wood and plant material is known to be disorganized. Structure formation in a particular direction is difficult to regulate accurately. The sizes and distribution of pores in CA could possibly be controlled by modifying the porosity of finished activated carbon with an organic binder and/or a pore-former or by applying a layer of organic polymer or hydrocarbon thermal decomposition products to the carbon substrate [1]. The goal of the present work was to study the effect of modifying the porous structure of previously carbonized Betula birch wood with betulinol and subsequent activation with KOH on the properties of the produced CA. It was found that thermochemical activation (800°C, 1 h) of previously carbonized (300–800°C) B. birch wood in the presence of KOH promoted the formation and development of micropores. The resulting carbon materials were distinctly porous and absorbed a broad spectrum of chemicals (benzene, hexane, CCl4, H2O, etc.). The carbonized (400°C) B. birch wood sample that was activated by KOH (3:1) (CBW-400/KOH) had the highest specific surface area (SBET 1980 m 2/g) and total pore volume (0.83 cm3/g) [2]. As the carbonization temperature was raised from 600 to 800°C, the KOH-activated CA were highly selective for the separation of a model mixture of H2(He) and CH4. Their separation coefficients (Ks) were 3.0–3.8, were used as criteria of the separating capability, and were estimated by chromatography. This represented a high degree of separation for He–CH4 [3]. The possibility of improving the Ks values by regulating the reactivity of the B. birch precursors that were carbonized at 500–800°C was studied. Existing pores were modified by the natural product betulinol (25 mass%) and then activated by KOH. Betulinol (betulin) is the pentacyclic lupane triterpene alcohol C30H50O2 with MW 442.7. It was isolated by extraction from B. birch bark. A coating of pyrolyzed carbon will form on the external surface of the carbon if the organic modifier is used under conditions where it is selectively decomposed (450°C). The carbon composite formed at this point is activated by KOH, which is effective on both components. As a result, modified CA with a controlled capability for selective adsorption and separation of H2(He)–CH4 mixtures were produced at 800°C. The effect of the organic modifier on the CA porous structure was studied using CBW (700°C) activated by KOH (CBW-700/KOH) as an example. Figure 1 shows the N2 adsorption isotherms at 77 K under standardized conditions (Fig. 1). The N2 adsorption isotherms for unmodified CBW-700/KOH (Fig. 1, 3) and for CA from pure betulinol (Fig. 1, 2), which was prepared for comparison under analogous KOH activation conditions, were characteristic of microporous materials. The shape of isotherm 1 was indicative of further pore development throughout the whole volume of CBW-700 because of modification with betulinol and subsequent activation by KOH. The fraction of micropores increased because pieces of pyrolyzed material were located near the entrances to larger pores. This shifted the pore-size distribution to a predominant size up to 1.8 nm (~90%) and gave a more uniform microtexture that was more favorable for He-CH4 separation. The Ks values of the modified CA from B. birch wood (Ks = 3.87–4.11) exceeded those of CA that were prepared analogously but were unmodified (Ks = 3.0–3.8) [3]. Table 1 shows that the modifying action of betulinol and subsequent activation by KOH were manifested best at carbonization temperatures of 600–800°C. Modified sample CBW-700 had the highest Ks value (4.11) for H2(He)–CH4 under controlled KOH activation conditions.

Integrated transformations of wood biomass to valuable chemicals and materials are described. They include the main biomass components separation, the conversion of cellulose to glucose, levulinic acid, biodegradable polymers and lignin – to nanoporous carbons. For wood fractionation on pure cellulose and low molecular mass lignin the methods of catalytic oxidation and exploded autohydrolysis are used. The processes of acid-catalysed hydrolysis of cellulose to glucose and levulinic acid were optimized. New methods of biodegradable polymers synthesis from lactone of levulinic acid and nanoporous carbons from lignin were suggested.

Publisher Summary Some dispersed supported metals (e.g., Pd or Rh) show catalytic activity in vapor-phase olefin hydroformylation. The reaction can be used for the study of migratory CO insertion as an elementary step in the alcohol formation and chain propagation in synthesis gas conversion. The modification of supported Rh by Fe(III) ions results in the enhancement of oxygenate formation in propylene hydroformylation. This fact has been accounted for by the promotion of migratory CO insertion due to its bi-site activation on surface bimetallic Rh–Fe3+ ensembles. To understand the role of CO adsorption mode in synthesis gas conversion on modified supported Pd catalysts, this chapter reviews propylene and hexene-1 hydroformylation on supported Pd + Ln and Pd catalysts. Some (Pd + Ln)/support catalysts having a low frequency mode of adsorbed CO show no activity in olefin hydroformylation. The level of catalytic activity of other catalysts is lower than that of unmodified Pd catalyst where the low frequency mode of adsorbed CO is not observed.

Studies of the properties of precipitated Fe−Mn catalysts in CO hydrogenation have revealed that samples precipitated from iron and manganese nitrates by sodium carbonate are more selective to olefins than those precipitated by ammonia. Difference in the catalytic properties is due to the different phase compositions of the catalysts.