It was found that 1% palladium catalysts supported on nanoglobular carbon (NGC) are quite effective in the hydroamination of furfural with nitrobenzene under mild reaction conditions. The catalytic performance strongly depends on the structure and morphology of NGC support. Among the studied catalysts, the sample based on the NGC, consisting of large carbon nanoglobules and containing highly dispersed palladium nanoparticles, exhibits good activity (78% conversion of furfural) and 83% selectivity to N-furfurylaniline. When studying the effect of reaction conditions, it was shown that an increase in both the reaction temperature and the catalyst-to-furfural ratio leads to an increase in the selectivity to by-products, while the hydrogen pressure has minor effect on the catalytic performance. Moderate temperature and hydrogen pressure (e.g., 90 degrees C and 15 bar H2) and low catalyst loading (0.1 g of catalyst per 1 g of furfural) are favorable to achieve high conversions (no less than 80%) and selectivity (80%). The stability test for one of the Pd/NGC catalysts shows that selectivity to the direction of hydroamination is 96-99% throughout all runs. However, a gradual decline in the activity for the hydrogenation of C = N bond in intermediate imine is observed from run to run, which is apparently due to the poisoning of the active sites by reagents and reaction products. Further directions in the study of Pd/NGC catalysts in the hydroamination of furfural should be aimed at optimizing reaction conditions and also at developing approaches to improving the catalyst stability.

New bimetallic Pd–Mn catalysts supported on the carbon material Sibunit have been obtained and studied for the process of producing ethylene by acetylene hydrogenation. The composition, structure, morphology and electronic state of the active phase have been studied in detail depending on the temperature of treatment in hydrogen and the Pd/Mn ratio by XRD, XANES, EXAFS, TEM, XPS. It has been found that the active species are the nanoparticles of intermetallic tetragonal structure Pd3Mn2 that formed during the treatment of Pd–Mn/Sibunit in H2 at 500 °C. Increasing the reduction temperature to 600–700 °C provides an increase in the proportion of the Pd3Mn2 phase due to more complete involvement of palladium in the interaction with manganese. Pd3Mn2 nanoparticles are less active but more selective than Pd nanoparticles due to changes in the geometry of active sites and their electronic state. It is shown that catalysts containing a twofold molar excess of Mn relative to Pd are characterized by the presence of more dispersed bimetallic particles than samples containing less manganese, due to which they are characterized by higher activity. Pd–Mn/Sibunit catalysts provide a high ethylene yield (up to 75

The modifying effect of cobalt on palladium in novel bimetallic Pd-Co catalysts supported on alpha-alumina was studied, and the catalytic properties of Pd-Co/alpha-Al2O3 samples in the direct selective hydrogenation of acetylene to ethylene were carefully investigated. It was shown that the temperature of catalyst treatment in hydrogen and the Pd/Co ratio are effective tools for varying nanoparticles composition of the Pd(1-x)Cox solid solution formed in the catalysts. Increasing the reduction temperature and decreasing the Pd/Co molar ratio leads to a gradual increase in the Co content in the Pd(1-x)Cox particles, which provides a slight decrease in activity, but an improvement in ethylene selectivity and the yield of the target product. Using XRD, XPS, HR TEM, TPD-C2H4 and TPR-H-2 it was found that an increase in the cobalt concentration in Pd(1-x)Cox nanoparticles suppresses the ability of the active component to activate hydrogen, enhances the electron interaction between Pd and Co and ensures rapid desorption of ethylene from the catalyst surface. The highest selectivity was demonstrated on supported Pd(1-x)Cox nanoparticles with the value of x > 0.4. It was also established that Pd-Co/alpha-Al2O3 samples with Pd:Co = 1:3 and 1:4 reduced in H-2 at 700 degrees C provide a high and stable ethylene yield at a level of 68 % due to the enhanced influence of cobalt on the electronic and geometric properties of palladium in Co-rich PdCo nanoparticles.

Carbon nanofibers with specified textural characteristics, obtained via catalytic chemical vapor deposition of various hydrocarbons, attract growing interest from both scientists and industrialists. In the present work, the optimal hydrogen content in terms of the carbon accumulation rate, process selectivity, and productivity of the Ni-Cu catalyst was found to be in the range of 40-70 vol%. As was revealed by the X-ray diffraction analysis, the catalytic particles are represented by a solid Ni-Cu solution based on the fcc lattice of Ni, and their composition does not depend on the hydrogen concentration. As found, the introduction of an optimal hydrogen amount into the initial reaction mixture decreases AD/AG (from 2.59 to 2.43) and increases both specific surface area (from 127 to 165 m2/g) and total pore volume (from 0.15 to 0.26 cm3/g). Thus, the effect of hydrogen on the decomposition of ethylene over self-dispersing catalysts is studied for the first time.

The carbonization temperature of carbon precursors before their activation is an important factor affecting the porous structure and properties of the resulting activated carbons. In this work сorrelation between the textural and adsorption properties of asphalt-based porous carbons and the carbonization temperature has been found. Additionally, the optimal carbonization temperature, and reasons why the carbonization temperature affects the main textural characteristics of the activated carbon were established. A series of porous carbons has been prepared from petroleum asphalt by a two-stage method, including carbonization of asphalt at different temperatures from 450 to 800 °C and KOH activation. To reveal the reasons of the correlation the carbonized samples were studied by TG-DTG, IR-Fourier, TEM methods. It is shown that the carbonization temperature effects on the structural defects, distance between the graphene layers, the reactivity and thermal stability of the carbonized asphalts. These specificities contribute to formation of porous structures of the activated carbons. The carbonization temperature 500–600 °С of the petroleum asphalt is found to be the optimal for further activation. The KOH activation of the petroleum asphalts carbonized at 500–600 °С provides microporous carbon with the high specific surface area (about 2000 m2g-1) and the CO2 uptake (3.3 mmolg-1). Additionally, the specific surface area of the activated carbons is shown can be predicted from the temperature of 50

Catalysts based on CoCuMgAl mixed oxides were synthesized and studied in the hydrogenations of furfural and 5-hydroxymethylfurfural under different conditions. The changes in the structural properties of the catalysts at different stages of their preparation were studied using a set of physical methods (XRD, SEM, and TEM). It was shown that the fine regulation of the chemical compositions of the mixed oxides (i.e., changes in the Co/Cu ratio) made it possible to vary the structure, morphology, and catalytic properties of the samples. The phase composition of catalysts with Co/Cu = 1 did not change during the catalytic reaction, although the initial catalysts had a less-homogeneous morphology. 5-hydroxymethylfurfural conversion was higher for the samples with Co/Cu = 1. Furfural conversion increased when raising the Co/Cu ratio. The selectivity toward furfuryl alcohol for the catalyst with Co/Cu = 2 under mild conditions of furfural hydrogenation was more than 99%. The results obtained are important for the development of the scientific foundations of the preparation of hydrogenation catalysts with a fine-tunable composition in order to obtain the desired hydrogenation products.

The research is devoted to the study of active component formation in the novel Pd-Co catalysts supported on carbon material Sibunit. It was shown that 0.5 %Pd-0.5 %Co/C samples exhibit high ethylene yield in the acetylene hydrogenation process due to the presence of fcc PdxCo(1-x) particles. According to in situ XRD-TPR analysis, solid solution formation begins during the reduction of samples in H2 at T >= 500 degrees C. Using the EXAFS, XRD and EDX it was established that H2-treatment at 500 degrees C leads to the formation of -Pd0.6Co0.4 particles and an increase in the reduction temperature to 600 and 700 degrees C is accompanied by the enrichment of the Pd-Co-phase with cobalt to -Pd0.5Co0.5 and -Pd0.45Co0.55 compositions, respectively. The ethylene yield on Pd-Co/C catalysts reduced at 500, 600 and 700 degrees C is 56, 66 and 68 %, respectively, which significantly exceeds the ethylene quantity obtained on monometallic Pd/C samples (-52 %). It is assumed that the excellent selectivity of Pd-Co/C samples treated in H2 at 600 and 700 degrees C is due to an increase in the amount of palladium atoms surrounded by cobalt and a change in the palladium electronic state (XPS).

Carbon black (CB) is widely used in the creation of various electronic devices due to its electrical conductivity and adsorption properties. The microstructure of electrically conductive CB samples was studied using transmission electron microscopy, multi-wavelength Raman spectroscopy and X-ray diffraction in this work. The relationship between the main characteristics of the structure of carbonaceous materials and electrical conductivity and adsorption properties was established. Using transmission electron microscopy, it was shown that the high values of σ and SBET of CB samples are due to the presence of hollow particles and changes in the organization of graphene layers. It was found that the parameter R, experimentally determined by X-ray diffraction, characterizing the fraction of carbon atoms of graphene sheets present as single layers, reliably correlates with the electrical conductivity σ of the studied carbonaceous materials. It was also found that the position of the D4 band, in the Raman spectra obtained with an excitation laser wavelength (λ) of 780 nm, correlates with both the electrical conductivity σ and the Brunauer–Emmett–Teller specific surface area (SBET) of the studied CB samples. Additionally, it was found that the intensity (area) of the D3 band obtained by mathematical decomposition of the Raman spectra recorded for the CB samples with λ = 532 nm is also interrelated with both the electrical conductivity σ and the SBET values. The obtained physicochemical dependencies are explained by the different structure of the graphene sheets and the additional polyene-like structures present in CB.

It was established that the surface functionality of nanoglobular carbon (NGC) can be effectively altered by treatment at temperatures of 573 – 1173 K in an inert atmosphere, without affecting the structure and morphology of the material as a whole. The destruction and loss of surface oxygen groups occurs as a result of this treatment, which is accompanied by a decrease in the concentration of paramagnetic centers. At a temperature of 1173 K, a restructuring and “smoothing” of the carbon surface apparently takes place, which is expressed by annealing of defects (sources of EPR signal). It was found that changes in the surface functionality of NGC affect the reducibility of supported palladium precursor and the formation of palladium nanoparticles, without causing changes in palladium dispersion state. The study of the obtained Pd/NGC catalysts in the practically important hydrogenation of 4-nitrobenzoic acid ethyl ester and furfural showed that thermal pre-treatment of the support affects the catalytic performance in these reactions. It is important that varying temperature of such pre-treatment over a fairly wide range, which has a significant impact on the functionality of the support surface, leads to only relatively small changes in the activity and selectivity of the resulting catalysts. In this regard, thermal pre-treatment of carbon support should be considered as an approach to fine tune the performance of carbon-supported palladium catalysts.

A mesophase precursor of carbon foam was synthesized by the pyrolysis of a propane-butane technical mixture; the precursor was shown to comprise polycyclic aromatic structures with the boiling point range from 200 degrees to 400 degrees C and above. The study revealed that the composition of the mesophase precursor can change with time, prolongation of which leads to the formation of higher molecular compounds. The formation of cellular carbon foam and its structure were studied; the possibility of obtaining closed and open cellular species was demonstrated. According to XRD, TEM and Raman spectroscopy data, the carbon material constituting the foam is nonporous and its nanostructure is typical of the carbon materials with a low ordering of graphene layers. A 70-80 nm thick carbon film in closed cellular carbon foam has a higher ordering of graphene layers and is readily removed in an air atmosphere (10 min, 850 degrees C) with the formation of open cellular carbon foam. The obtained carbon foam possesses high chemical and thermal stability and could be applied in the adsorption catalytic technologies. It was shown in experiments that this carbon material with a density 0.02 g.cm(-3) and oil capacity above 20 g.g(-1) is promising for use as a regenerable petroleum sorbent.

Single phase CuCoMgAl-layered hydroxides were obtained by making fine adjustment to their composition through changing the (Co + Cu)/Mg = 0.5; 1; 2; 3 and Co/Cu = 0.5; 1; 2 ratios. The rise of Co/Cu in systems contributed to the increase in their thermal stability. CuCoMgAl-catalysts showed high selectivity of carbonyl group hydrogenation in furfural and 5-hydroxymethylfurfural. In furfural hydrogenation, the selectivity to furfuryl alcohol was more than 99%, and in 5-hydroxymethylfurfural hydrogenation, the selectivity to 2,5-hydroxymethyl furfural was 95%. The surface of the samples with different Co/Cu after calcination and reduction was the same and had a «core-shell» structure (TEM). «Core» consisted of Cu and Co metallic particles. «Shell» consisted of CuCoMgAlOx mixed no-stoichiometric spinel oxides. There was no sintering or change in size of the metallic particles after the reaction. For the sample with Co/Cu = 1, their phase composition after reaction remained unchangeable. The increase of Co/Cu led to the formation of an X-ray amorphous phase after the reaction. This suggests the decrease in structural stability of this sample. The obtained results prove the prospects of using bimetallic CoCu-systems for hydrogenation of furan aldehydes, and opens up new directions for further research and improvement.

Modification of the surface of carbon black (CB) of the N326 is performed by treatment in an aqueous solution of sulfanilic acid with the addition of sodium nitrite. It is shown that the covalent modification of sulfonic groups in the amount of 0.25 up to 2.62 μmol/m 2 on the carbon surface does not result in any substantial change in the specific surface area (84–85 m 2 /g) and dibutyl phthalate absorption number of the aggregates of carbon black (of 70–76 cm 3 /100 g). A sample of CB with the density of coating with sulfonic groups of 2.62 μmol/m 2 is distinguished by the monomodal size distribution of carbon particles at an average diameter of about 250 nm and makes it possible to form highly stable aqueous suspensions.

Nickel catalysts with carbon-mineral supports derived from sapropel were synthesized; the effect exerted by the nature of the support (type of the initial sapropel) and active component precursor on the activity of the catalysts in the model reaction of liquid-phase nitrobenzene hydrogenation was studied. The catalysts, synthesized using the support with a smaller fraction of carbon, were more active irrespective of the precursor nature. The highest activity was observed for the catalysts synthesized from nickel nitrate and formate; nitrobenzene conversion was 65% and 51%, respectively, after 1 h of reaction. The catalysts retained high activity after six reaction cycles at 100% aniline selectivity. The presence of sulfur in the nickel precursor deteriorated the catalytic activity (convection less than 3%) due to formation of the sulfide phase.

Phase-homogeneous LiFePO4 powders have been synthesized. The content of impurity crystalline phases was less than 0.1%, according to synchrotron diffractometry (SXRD) data. Anisotropic crystallite sizes L¯Vhkl were determined by XRD. A low resistance covering layer of mechanically strong ferric-graphite-graphene composite with impregnated ferric (Fe3+) particles < 10 nm in size increases the cycleability compared to industrial cathodes. In accordance with the corrosion model, the destruction of the Fe3+-containing protective layer of crystallites predominates at the first stage, and at the second stage Fe escapes into the electrolyte and to the anode. The crystallite size decreases due to amorphization that starts from the surface. The rate capability, Q(t), has been studied as a function of L¯Vhkl, of the correlation coefficients rik between crystallite sizes, of the Li diffusion coefficient, D, and of the electrical relaxation time, τel. For the test cathode with a thickness of 8 μm, the values of D = 0.12 nm2/s, τel = 8 s were obtained. To predict the dependence Q(t), it is theoretically studied in ranges closest to experimental values: D = 0.5 ÷ 0.03 nm2/s, τel = 8/1 s, average sizes along [010] L¯1 = 90/30 nm, averaged r¯ = 0/1.

CoAl-hydroxides with Co/Al = 2 and 4 were synthesized by traditional coprecipitation method and mechanochemical route. Structure properties of the samples on the all preparation stages of the catalysts, the transformations occurred during cobalt reduction from corresponding oxides, textural characteristics of calcined and reduced samples, as well as size, morphology and composition of the particles that formed after high temperature treatments were studied in detailed. It was established, that synthesis procedure of CoAl-hydroxides has a significant impact on phase composition and properties of obtained systems. The phase of layered double hydroxide formed only when using coprecipitation method. The mechanochemical approach allowed to obtained the materials with higher specific surface area. According to TEM data, the samples prepared by coprecipitation (after oxidative and reductive treatments) had a “core-shell” structure where metallic atoms of Co were in core and shell consisted of CoAl-spinel. The samples synthesized by mechanochemical route had Co nanoparticles with high dispersion on the surface. The catalysts based on CoAl-systems prepared by mechanochemical method were more active in the furfural hydrogenation. Conversion of furfural achieved 97% for the sample with Co/Al = 4. Herewith, selectivity of furfural formation for all studied catalysts was almost 100% irrespective of synthesis procedure and Co/Al ratio.

Carbon-mineral supports obtained by carbonization of sapropels were used to synthesize nickel-containing catalysts. A study was performed to reveal the effect of catalyst composition (the active metal and the support nature) on the catalytic hydroliquefaction of sapropel organic matter aimed to obtain liquid products used as fuels. This is the first study where both the material for catalytic transformations and the catalyst support were obtained from the same natural raw material (sapropel). Catalysts based on a support prepared from mineral-type sapropel showed higher activity compared to catalysts with a support prepared from organic sapropel both in the case of monometallic nickel systems and with the introduction of a second metal (molybdenum or copper). The liquid products of hydroliquefaction included predominantly the nitrogen- and oxygen-containing compounds (aliphatic and aromatic acids, phenols, cresols, alcohols, pyrazines, and pyridines). The nickel-copper catalyst with support based on mineral sapropel provided a deeper conversion of the organic matter of sapropel, with a hydrocarbon content of up to 30 wt. %.

Ni(Mg)Al-layered hydroxides with molar ratios of (Ni + Mg)/Al = 2, 3, 4 and Ni/(Ni + Mg) = 0.1, 0.3, 0.5, 0.7 were synthesized by mechanochemical activation. It has been proven that the phase composition of the samples was presented by a single hydrotalcite phase up to Ni/(Ni + Mg) = 0.5. For the first time, catalysts based on Ni(Mg)Al-layered hydroxides prepared by a mechanochemical route have been studied in the reaction of furfural hydrogenation. The correlation between furfural conversion, the selectivity of the products, and the composition of the catalysts was established. The effect of phase composition, surface morphology, and microstructure on the activity of the catalysts was shown by XRD, SEM, and TEM. It was found that catalysts with Ni/(Ni + Mg) = 0.5 have the highest furfural conversion. Herewith, the product selectivity can be regulated by the (Ni + Mg)/Al ratio.