Voprosy khimii i khimicheskoi tekhnologii (Issues of Chemistry and Chemical Technology)

4-6

Authors: O.A. Pivovarov

On the occasion of 85th anniversary, the history, current state and prospects for further development of the Ukrainian State University of Chemical Technology are reviewed. The role of prominent chemists in the foundation and establishment of the University and its prestige in Ukraine and abroad is shown.

25-45

Authors: F.I. Danilov, V.S. Protsenko, Yu.E. Sknar

The investigations devoted to the electrochemical synthesis of composite coatings are systematically reviewed. The co-deposition of nonmetallic phase is shown to proceed via two main mechanisms. The first mechanism presupposes that the particles of nonmetallic phase are initially added to the suspension electrolyte and then incorporated into the deposit. According to the second mechanism of the synthesis of composite electrochemical coatings, the dispersed phase is formed in the near-electrode layer as a result of electrochemical or chemical transformations with the participation of electrolyte constituents, the particles of the dispersed phase being not initially introduced into the bulk solution but generated in situ directly in the near-electrode zone or on the electrode surface. The electrodeposition of composites from suspension electrolytes is illustrated by the electrochemical syntheses of Fe/ZrO2, Fe/TiO2 and Ni/ZrO2 coatings. The kinetics of co-deposition proved to obey the theory developed by Guglielmi. Methanesulfonate electrolytes can be used for composites electrodeposition. The methanesulfonate electrochemical systems are distinguished by their high productivity, enhanced content of nonmetallic phase in coatings, and valuable physicochemical properties of deposits obtained. The fabrication of composites by the direct formation of a dispersed phase in the near-electrode layer in the course of electrolysis is illustrated by the deposition of Ni/CeO2 composite from the methanesulfonate electrolyte and Cr/C composite (i.e. containing chromium carbides) from the sulfate electrolyte on the basis of Cr(III) salts. The microstructure and some physicochemical and service properties of the obtained nanostructured composite coatings are characterized.

53-64

Authors: V.I. Markov, O.K. Farat, S.A. Varenichenko, E.V. Zaliznya, Yu.P. Stroev

This review contains data on the reactivity of heminal azine − 5',6',7',8'-tetrahydro-1'H spiro[cyclohexane-1,2'-quinazolin]-4'(3'H)-one and the chemical properties of his rearrangements products. The main results of the investigations are presented which have been performed at the TOSPhP department of Ukrainian State University of Chemical Technology during last five years. We have studied in detail the Mannich aminoalkylation of this compound with primary amines which leads to the formation of a heterocyclic system containing an annelated azabicyclic fragments. The hydrolysis of the indicated spirans gives 3-azabicyclo[3.3.1]nonanes. These compounds show a variety of biological activity (for instance, analgetic and antimicrobial one). Hence, the development of new methods for preparing novel polycyclic 3-azabicyclo[3.3.1]nonanes is an actual goal. We investigated the formylation of 5',6',7',8'-tetrahydro-1'H-spiro[cyclohexane-1,2'-quinazolin]-4'(3'H)-one and discovered a new multistage domino reaction which enables to obtain tricyclic acridine systems due to the deep rearrangement of the carbon skeleton. In the present work we showed that the rearrangement of 5',6',7',8'-tetrahydro-1'H-spiro[cyclohexane-1,2'-quinazolin]-4'(3'H)-one and its analogues under Vilsmeier-Haack conditions is of a general nature. The reaction is sensitive to increased temperatures and in the case of some derivatives it is nonselective and gives a hardly separable mixture of resinous products. It is proposed to consider the rearrangements of azine, which are based on pyrimidine-to-pyridine transformation induced electrophile attack, as an AERORC-process.

69-73

Authors: O.S. Panteleieva, V.I. Tkach

The present paper is devoted to the interaction between organic cation of Pachycarpinum and heteropolyanions (HPA) of Keggin structure of 12-molybdophosphatic heteropoly acid РМо12О403–. The marginally soluble associates obtained have been used as electrode-active substances for the synthesis of the plasticized membranes of ion-selective electrodes which are reversible with respect to the organic cation of Pachycarpinum. We developed a new technique for the determination of the content of pahicarpine hydroiodide in a substance and aqueous extracts of lupine seeds and roots; the technique is based on the potentiometric method with the use of an ion-selective electrode which is sensitive to the organic cation of pahicarpine hydroiodide. The HPA of Keggin structure РМо12О403– was chosen as an analytical reagent. This analytical reagent is used due to its ion-exchange properties and ability to easily rebuild; it can deposit large organic cations to form poorly soluble compounds of constant composition which are soluble in organic solvents and insoluble in water. In the course of the interaction between HPA and organic cation of pahicarpine hydroiodide, a reaction occurs with the formation of a marginally soluble compound with an ion-associative bond nature. The synthesized compound is used as an electroactive substance for the ion-selective electrode which is reversible with respect to the organic cation of pahicarpine hydroiodide. Thus, according to the data obtained, an associate of the general formula (Pah)3PMo12O40 was used as an electroactive substance for the developed ion-selective electrode. The developed ion-selective electrode with a plasticized polyvinylchloride membrane is sensitive to the organic cation of pahicarpine (Pah1+). The proposed analytical techniques of a direct potentiometric determination of Pachycarpinum in a substance and aqueous extracts of lupine seeds and roots are characterized by sensitivity, rapidity and accuracy.

78-85

Authors: V.D. Barsky, G.A. Vlasov, А.А. Pivovarov, A.V. Kravchenko

In any spatial zone the main factor, which forms variety of chemical composition, structure and properties of coal, is the time from the beginning of "geological history" of maternal plant residues. Furthermore, on any segment of the "geological age" even in relatively close spatial zones the coals of various "chemical age" can be formed because of varying intensity of natural impacts and, first of all, temperature and pressure. Since the latter ones "after all this time" are not actually identifiable, quantitative description of metamorphism was carried out by establishing time-dependent patterns of elemental composition changing at the background of its "random", but causative fluctuations. The report deals with patterns of changing in the course of metamorphism of the elemental composition of solid fuel and mathematical model built for description of the said patterns as a function of carbon content. With the use of experimental data of artificial carbonization it is shown that it represents an experimental model of natural metamorphism. The elemental composition of solid fuel "molecule" has been formulated. Investigation of the dynamics of carbonization changes allowed defining specific points on the axis of metamorphism, and drawing up the material balance of this process showing that coking coals are concentrated on the axis of metamorphism in the narrow region near the point where 16 hydrogen atoms fall on each oxygen atom in solid fuel "molecule".

92-103

Authors: A.I. Nesterenko, Y.S. Berlizov

The use of cavitation leads to an increase in the yield of light oil by the thermal cracking of oil stock. It has been experimentally established that the yield of diesel fractions depends on the composition and properties of oil stock as well as the cavitation parameters, such as temperature, pressure, viscosity, volume flow rate, number of cavitation cycles, geometry of the centrifugal vortex chamber etc. In addition, the process occurs at a high temperature and pressure and oil stocks are highly corrosive. Therefore, it is very difficult to ascertain the influence of cavitation by experimental studies. Thus, we performed the computer simulation of the process under consideration. It is shown that the axial, radial and peripheral velocities of raw materials in the centrifugal vortex chamber pronouncedly differ in their magnitude. The full velocity is high and reaches 43 m/s on the vortex surface. It is concluded that the cavitation region must be on the very vortex surface where the intensification of the hydrocarbons cracking takes place. The parameters of the cavitation region are determined from static pressures of a liquid in all points of the cavitation apparatus. The distribution of the static pressure of the liquid in the centrifugal vortex chamber is complicated, namely the cavitation region is a hollow truncated cone, inside which a cylindrical steam vortex is. The formation of a turbulent layer expands the cavitation region; the shape and size of the cavitation region being calculated based on the parameters of a real centrifugal vortex chamber.

119-124

Authors: A.Yu. Poloz, Yu.R. Ebich

The dispersed structure of epoxy resin compositions based on ED-20 filled with silicon carbide with varying dispersion degree is analyzed. These epoxide compounds are characterized by enhanced hardness on the Moos scale to ensure the wear resistance of composite materials. The density packaging fillers, average distance between particles fillers, and "free and specific free volume fillers" are chosen as parameters of the composites dispersion structure. The influence of "free volume fillers" on the dispersion degree is shown. When manufacturing highly filled epoxide compositions, it is worthwhile to introduce firstly filler with small particles for which a change of this parameter has virtually no effect on the average distance between the particles of the filler. Then coarse fillers should be introduced for which the dependence involved is significant.

4-6

Authors: K.S. Burmistrov, K.A. Shreiber, B.V. Murashevich, N.V. Toropin

A handy method for the synthesis of 1-(4-hydroxyphenyl)-3-(4-aminophenyl)-5-ethyl-1,2,4-triazole by the reduction of respective nitro compound is developed. The reactions of the R-sulfonylation of aminotriazole at the amino group by the methane sulfochloride and arylsulfochlorides are investigated. The 1-(4-hydroxyphenyl)-3-(4-R-sulfonylamidophenyl)-5-ethyl-1,2,4-triazoles have been synthesized, these compounds being not described previously. The structures of new synthesized compounds are proved by means of 1H NMR spectroscopy. The spectra of a potential biological activity of the synthesized 1-(4-hydroxyphenyl)-3-(4-aminophenyl)-5-ethyl-1,2,4-triazoles and their derivatives are obtained by using the software "Prediction of Activity Spectra for Substances". Keywords: 1,2,4-triazole; amino group; methane sulfochlorides; arylsulfochlorides.

13-19

Authors: L.M. Grishchenko, T.M. Bezugla, V.V. Trachevskiy, A.V. Vakaliuk, A.N. Zaderko, V.E. Diyuk, O.V. Ishchenko

Carbon fibers are characterized by high thermal and mechanical stability; they are a promising material for creating highly selective adsorbents, catalysts and catalyst carriers. In order to functionalize the surface, the carbon fibers were treated with bromine in the liquid phase and in the low-temperature gas discharge. The physicochemical properties of brominated carbon fibers were studied. The plasma-chemical treatment was shown to be more effective in comparison with the liquid phase bromination. The concentration of surface bromine proved to depend on the processing time. The obtained materials can be used as precursors for the synthesis of catalysts containing acid SO3H groups on the surface. It was found that the pre-bromination provides grafting more SO3H groups in the surface layer. Catalysts that were prepared on the basis of the plasma brominated precursors exhibited a higher catalytic activity in the isopropanol dehydration; they were more stable under the condition of this reaction compared with the catalysts based on fibers brominated in the liquid phase.

26-29

Authors: K.V. Makarova, A.S. Makarov, D.P. Savitskiy

The investigation on the effect of water-soluble polymers on the rheological properties of water-coal slurries based on low-ash coals, subbituminous coal and anthracite has been performed. When the concentration of the polymer is equal to 0.01 g per 100 g coal, the systems under study have not only the lowest viscosity but also the highest stability. An increase in the polymer content results in an increase in the slurries viscosity. The water-coal slurries containing polyacrylamide, polyvinyl alcohol and polyvinylpyrrolidone are unstable; the particles being rapidly precipitated forming spongy sediments. The sedimentation stability of water-coal slurries increases until 15 days when carboxymethyl cellulose is applied as a stabilizing agent.

33-37

Authors: G.V. Sokolsky, S.V. Ivanov, A.B. Velichenko, N.D. Ivanova, E.I. Boldyrev

Manganese(IV) oxide electrodeposition process from fluorine-containing electrolytes of Mn (II) are studied in the presence of sodium cations and without them. The differences in cyclic voltammogramms (CVA's) are detected and discussed in terms of the phase composition of electrodeposited samples according to the results of X-ray diffraction study. The content of hollandite phase should be taken into account in the first place. The appearance of an additional peak in the forward scan of CVA's in the presence of Na+ can be explained as a result of an additional pathway of the anode process involving sodium cations and reduced manganese surface states (i.e. Mn(II)); this pathway being accompanied by the formation of tunnel hollandite phase. We concluded that some chemical steps may affect the formation of hollandite phase component.

44-47

Authors: V.I. Goleus, An.A. Saley

Using a multiple regression method, a correlation equation is developed which allows calculating the viscosity of molten borosilicate enamels as a function of their composition and temperature. The regression coefficients are determined by the least-squares method using the experimental-statistical sample of glasses which compositions and viscosity are taken from the electronic database SciGlass. Depending on the composition of glass samples, the values of the melt viscosity change in the range from 100.13 to 107 P in the temperature range from 885 to1825 K, the sample mean of lgη and its standard deviation being equal to 3.56±1.28 P. The proposed mathematical model is adequate to the experimental data; it allows calculating the values of lgη for the melt borosilicate glasses with a standard deviation of ± 0.2 P. Such accuracy is quite sufficient for the selection of glass frits composition for the enamel coatings with the specified firing temperature range. The analysis of the changes in the viscosity of borosilicate melts as a function of Li2O, Na2O, K2O, B2O3 and SiO2 content in their composition shows that the enamel coatings can be obtained on the basis of glass frit with a firing temperature less than 950 °C; to this end, the SiO2 content should be less than 55 mol% when the total content of the basic components should be 80±3 mol%.

54-61

Authors: Y.V. Kalashnykov, D.V. Gura, A.N. Kalashnykova, N.V. Nikolenko

In this paper a mathematical model is proposed which aims to optimize the conditions of the synthesis of iron-molybdenum catalyst via the heat treatment process of ammonium molybdoferrates(II) precipitates with a molar ratio Mo:Fe = 2.2 in an oxidizing environment. In our calculations the experimental data on the kinetic parameters of the following steps are taken into account: the dehydration, the decomposition of ammonium molybdoferrate(II) with the formation of FeMoO4 and MoO3, the oxidation of Fe(II) ions with the formation of Fe2(MoO4)3 phase and the decomposition of the impurity phases of ammonium sulfate and iron(II) sulfate. The kinetic curves have been plotted for the distribution of component mole fractions during oxidative thermal treatment. The rate of the heat treatment process is limited by the decomposition of iron (III) oxysulfate and sulfate impurities formed during the oxidation of ammonium molybdoferrates(II). The optimum parameters of the thermal decomposition process of ammonium molybdoferrates(II) have been determined in order to obtain a mixture of iron molybdate with an excess of molybdenum trioxide, the mixture does not contain any impurities of sulfate compounds. The results of the analysis of the developed mathematical model are in good agreement with the experimental determination of the total sulfur content and the experimental X-ray diffraction data of the samples which were calcinated at various periods of time.

68-72

Authors: A.Yu. Poloz, Yu.R. Ebich, S.V. Zhiltsova

The estimation of the thermomechanical properties of epoxy compositions based on the resin ED-20 was conducted, these compositions being cured by polyethylene polyamine at 20°C. The temperature was varied in the range from 60 to 140°C and the additional heat treatment was performed to achieve the most complete involvement of epoxy groups in the spatial grid of resin. The differences in the thermo-mechanical properties of epoxy polymers subjected to the heat treatment both in a glassy state (up to 100oC) and in a rubbery one (from 120 to140oC) were shown. It was suggested to perform the heat treatment of epoxy polymers at a temperature which is close to the glass transition temperature. A non-monotonic variation of the thermo-mechanical properties of the wear-resistant epoxy composites filled with silicon carbide was established when a filler concentration changes. The application of polydisperse silicon carbide leads to an increase in the glass transition temperature of epoxy composites that allows expanding the temperature operational range of the use of products made from these composites.

78-83

Authors: T.G. Filinska, O.V. Chervakov, K.O. Gerasymenko, M.O. Tkachov, А.O. Filinska

We investigated the glycerolysis process of chicken fat and waste palm oil using heterogeneous sulfonated polymeric catalyst SAC-Ph-30(L). The catalyst is synthesized by reacting of phenolsulfonic acid-formaldehyde condensation products with polyvinyl alcohol in aqueous solution, the catalyst containing lignin additionally. The glycerolysis of raw fat should rationally be carried out at the temperature of 100°C; this indicates that the process is energy-saving as compared to traditional technology. The duration of glycerolysis process depends on the type of fatty raw material (fatty acid residues of the triacylglycerol); it takes 4 h for chicken fat and 8 h for waste oil palm, correspondingly. The surface-active properties of chicken fat and waste palm oil glycerolysis products (i.e. mono- and diacylglycerols) have been estimated. It is shown that the industrial emulsifiers DIMODAN HP and CREMODAN 60 VEG may be fully replaced with the waste oil palm glycerolysis products. The glycerolysis products can be used in food products as emulsifiers in a reverse type of water-fat emulsions (i.e. margarine).

4-8

Authors: V.Y. Vishnevskiy, V.A. Кucherenko

A study of spatial structure is an important part of the research of activated carbons (ACs) prepared by alkali activation. The spatial structure determines three-dimensional framework properties and technological characteristics of ACs such as hardness, abrasion, conductivity and others. The present work is devoted to the X-ray diffraction investigation of ACs prepared by the alkali activation of Donbass coals covering a wide range of rank (Cdaf = 70.4-95.2%). The spatial structures of ACs depend on native coal types and is characterized by the presence of crystallites with interlayer distance (d002) from 0.359 to 0.432 nm, graphene layers number (N) from 1.6 to 2.8, and C-atom number (Nc) from 165 to785. Spatially ordered aliphatic and polynaphtenic fragments were not identified, probably due to their high termolability leading to their destruction under alkali activation. Peaks observed at distances from 0.75 to 0.01 nm and from 1.03 to 1.13 nm are corresponded to the scales of micro- and subnanopores.

17-21

Authors: S.A. Konovalova, A.P. Avdeenko, A.G. Sergeeva, S.A. Goncharova, M.V. Polischuk

The 1,4-binding of a thiocyanate-ion at the thiocyanation of N-substituted 1,4-benzoquinonmonoimines via a sulfur atom has been earlier suggested to be typical of quinonmonoimines with low LUMO energy, whereas such binding proceeds via a nitrogen atom of thiocyanate for quinonmonoimines with high LUMO energy. The thiocyanation of N-arylaminocarbonyl-1,4-benzoquinonemonoimines leads to the formation of 1,3-benzoxathiol-2-ones and 2-imino-1,3-benzoxathioles which are obtained through the initial 1,4-binding of a thiocyanate-ion via a sulfur atom, 1,3-benzoxathiol-2-ones being the products of hydrolysis of 2-imino-1,3-benzoxathioles. According to the quantum-chemical calculations, the N-arylaminocarbonyl-1,4-benzoquinonemonoimines have lower LUMO energy than N-acetyl- and N-phenilacetyl-1,4-benzoquinonemonoimines, the latter give the products of binding both via a sulfur atom and via a nitrogen one. This confirms the fact that the LUMO energy of an initial quinonemonoimine is a key factor in the thiocyanation of N-substituted 1,4-benzoquinonmonoimines, the binding of thiocyanate-ions proceeds via a sulfur atom under orbital control.

29-34

Authors: O.S. Miagkota, N.E. Mitina, V.V. Vistovskiy, A.V. Shapoval, A.S. Voloshynovskiy, P.N. Gmurin, A.S. Zaichenko

In this paper the synthesis of BaF2 and CaF2 nanoparticles is discussed. The synthesis occurs via cations exchange reaction in micellar zones formed by oligomeric surfactants in water. The heterofunctional oligoperoxide surfactants serve as soft templates in nanoparticles synthesis. The presence of oligoperoxide surfactants in solution results in decreasing the BaF2 nanoparticles sizes and significant narrowing the size distribution. The particles size was determined on the basis of X-ray diffraction analysis using the Scherrer equation. The nature, structure, molecular weight and surface activity of oligomers applied as the templates affect the size and the size distribution of BaF2 and CaF2 nanoparticles obtained. The features of the adsorptive modification of BaF2 nanoparticles surface by oligoperoxides are investigated. The area on the nanoparticle surface that is occupied by the adsorbed oligomers molecule as well as the packing density of molecules in an adsorptive layer depends on the adsorption value and nature of oligomeric surfactants. The area on the nanoparticle surface that is occupied by the adsorbed oligomers molecule drops to some critical value with an increase in the oligomer content in solution.

40-43

Authors: O.S. Panteleieva, H.P. Akritidu, M.M. Kucher, V.I. Tkach

A method of quantitative determination of pahicarpine hydroiodide (i.e. d-sparteyin hydroiodide) in a substance is developed. The method is grounded on amperometric titration with using 12-molibdophosphate heteropolyacid as an analytical reagent. 12- molibdophosphate heteropolyacid has a stable composition and unique ion exchange and redox properties; it forms stable ionic associates with organic cations containing nitrogen which are characterized by a low solubility in water and a sufficient one in organic solvents. The results of amperometric titration indicate that the organic pahicarpine cation interacts with the 12- molibdophosphate heteropolyanion in a molar ratio Pah1+:PMo12O403– = 3:1; and the reaction under study proceeds stoichiometrically in aqueous solutions within pH from 4.0 to 5.5 (3Pah1++PMo12O403– → (Pah)3PMo12O40) with the formation of a stable water soluble ion associate. The technique proposed is characterized by rapidity (it takes about 10-12 min), sufficient sensitivity and simple quantification of pahicarpine hydroiodide substances in aqueous solutions within the concentration range of 1.0∙10–2 to 1.0∙10–4 mol/l.

48-52

Authors: I.B. Sobechko

The values of enthalpies and dissolution entropies of 5-(2-nitrophenyl)-furane-2-carbaldehyde, 5-(2-nitrophenyl)-furane-2-carboxylic and 3-[5-(2-nitrophenyl)-furane-2-propionic acids in acetonitrile, bimethylketone, propanol-2, ethyl acetate are determined based on the temperature dependence of solubility. The entropies and enthalpies of mixing of the compounds at 298 K are calculated using the enthalpies of melting. The analysis of the influence of intermolecular interactions in the solutions on the solubility of the compounds and their enthalpies of mixing is conducted. It is shown that in 5-(2-nitrophenyl)-furane-2-carbaldehyde the contribution in the energy of intermolecular interactions of the dispersed component is more than 90%. The 5-(2-nitrophenyl)-furane-2-carboxylic and 3-[5-(2-nitrophenyl)-furane-2-propionic acids in the liquid state exist in the form of dimers linked by two hydrogenous bonds (with ЕН ≈45±5 kJ), these dimers being destroyed during the vaporization (T>450 K). During their solving (T<330 K) in the investigated solvents, the dimers are stable, they significantly reduce the polarity of the molecules and their ability to participate in the intermolecular interactions with the molecules of the solvent. This explains some anomalies established in the experimental part of the work.

60-65

Authors: S.V. Zhil’tsova, V.M. Mikhal'chuk, R.I. Lyga, N.G. Leonova, P.M. Pavlii, K.А. Volyanyuk, V.А. Beloshenko

Sol-gel method was used to obtain epoxy-titania composites based on titanium tetrabutoxide, epoxy resin and amine hardener Jeffamine®T403. The results of X-ray diffraction analysis indicated the formation of the amorphous TiO2 form during the synthesis procedure. Scanning electron microscopy data revealed that the filler particles size reached up to 10 μm for the composites based on epoxy-diane resin ED-20; the particles had a tendency to aggregate. The use of epoxy resin with saturated cycles EPONEX 1510 resulted in the transparent composites formation with a uniform distribution of TiO2 particles in the polymeric matrix with the size of less than 0.5 μm which contributed to the high optical transparency of the synthesized materials. The results of gas-volumetric analysis showed that the presence of the in situ formed titanium dioxide at a concentration of 0.5 to 1 wt.% caused the appearance of the induction period and a decrease in the maximum rate of oxygen uptake. With an increase in the TiO2 content in the composites up to 3 wt.%, the amount of low molecular weight compounds (i.e. sol-fraction) in the polymeric matrix increases, the oxidation rate grows and the induction period duration diminishes. The results of derivatographic analysis indicate that the main stage of the composites degradation occurs at higher temperatures compared to the epoxy polymer, while there is a substantial change in the velocity and temperature limits of the individual stages of the organic constituent decomposition.

70-76

Authors: N.Ya. Kuzmenko, S.N. Kuzmenko, O.V. Skrynnik

Synthesis, characteristics and physicochemical properties of oligomers are described which have been obtained by the reaction of the interesterification of tris[[tri(butoxy)titanate]boran by 2-(dimethylamino)ethanol. At room temperature these compounds are transparent liquids with a reddish-brown tint; they are very soluble in alcohols and aromatic- and chlorinated hydrocarbons; however, they are only partially soluble in ethers, esters and aliphatic hydrocarbons. The structure of the substances under study has been verified by elemental analysis, molecular mass measurement, infrared and 1H NMR spectroscopies. The synthesis of these compound is shown to be equilibrium. The synthesis of products, in which the degree of the substitution of butoxy groups in tris[[tri(butoxy)titanate]boran for 2-(dimethylamino)ethoxy groups of the 2-(Dimethylamino)ethanol is more than 6, is complicated by steric effects. A monotonic increase in the absolute refraction index and density of products synthesized is observed with an increase in the ratio of tris[[tri(butoxy)titanate]boran to 2-(dimethylamino)ethanol from 1:1 to 1:9 (mol), respectively. It is shown that a part of 2-(dimethylamino)ethanol is not interesterificated with tris[[tri(butoxy)titanate]boran and leaves the reaction zone as an azeotropic mixture together with butyl alcohol evolved. The joint presence of butyl alcohol and 2-(dimethylamino)ethanol in reactor does not result in the synthesis of their ether under reaction conditions.

82-86

Authors: L.A. Snizhko, N.L. Gurevina, O.А. Kalinichenko, D.A. Misnyankin, V.A. Golovenko

The qualitative model of electro- and thermochemical processes that determine the oxide growth in anodic spark mode in alkaline solution with additions of inorganic polymers is proposed. The weight of the coatings and gas output at the sparking voltage (>450 V) are determined by changes in spark sizes and path of anodic surface beneath them. It is suggested that the main processes under sparking are aluminium dispersion and interaction between aluminium particles and water vapour. Mass of dispersed aluminium, thickness of oxide film and hydrogen volume are calculated in accordance with stoichiometric equations taking into account the spark diameters, density of metal and part of the electrode surface under discharges. Calculated film thicknesses coincide with the experimental values obtained by voltastatic electrolysis. It is shown that the electrochemical stage of anodic spark oxidation process is responsible for a primary barrier layer (up to 1 m) formation. The subsequent electrical breakdown of this layer causes secondary thermochemical reactions. It is established that at the frequency range of 50 to 120 Hz the efficiency of the process increases.

3-8

Authors: D.V. Girenko

In this work, we studied the effect of the addition of sodium bicarbonate on the kinetics of the synthesis of sodium hypochlorite from 0.15 M NaCl solution in an electrolytic cell with undivided electrode spaces. In the presence of NaHCO3, pH buffering occurs in near-electrode spaces, and, as a result, the rate of oxygen reduction on the cathode increases with the generation of hydrogen peroxide. Buffering of the near-anode space leads to an increase in the surface concentration of oxygen-containing particles of radical type OHads which promotes the emergence of peroxycarbonate anion C2O62− or carbonate anion-radical CO3−• in the solution. The formation of relatively long-lived peroxy-compounds results in transferring the part of the electrode surface processes to the bulk solution that reduces the concentration of active chlorine and the additional accumulation of chlorate. At the NaHCO3 concentration of 0.02 M, the chlorate content increases 2.5-3 times as compared with the initial solution. Thus in order to prepare hypochlorite solutions with the smallest possible amount of chlorate, it is necessary to use initial solutions which are free from carbonates, bicarbonates, and dissolved carbon dioxide, or to carry out the preliminary decarbonization.

13-18

Authors: S.A. Konovalova, A.P. Avdeenko, M.V. Polischuk, A.L. Yusina

Earlier we synthesized N-carbamoyl-1,4-benzoquinonemonoimines being analogues of N-arylaminocarbonyl-1,4-benzoquinonemonoimines which reacted with sodium arylsulphinates mainly under 1,4-addition. Only 2,6-dimethyl-N-arylaminocarbonylderivatives gave products of 6,1-, 1,6- and 6,3-addition. To compare the reaction ability of N-carbamoyl- and N-arylaminocarbonyl-1,4-benzoquinonemonoimines we studied the interaction of N-carbamoyl-1,4-benzoquinonemonoimines with sodium 4-tolylsulphinate. The products of 1,4-, 6,1-, 1,6- and 6,3-addition have been obtained as a result of reaction of N-carbamoyl-1,4-benzoquinonemonoimines with sodium 4-tolylsulphinate. The addition direction depends on substituent position in quinoid ring of quinoneimine more considerably than in case of N-arylaminocarbonyl-1,4-benzoquinonemonoimines. On the basis of experiment results and quantum-chemical calculations it is proved the products of 6,1- and 1,6-addition form by ion-radical mechanism.

36-39

Authors: O. Shmychkova, T. Luk'yanenko, A. Piletska, A. Velichenko

The coatings obtained from a methanesulfonate bath are shown to be almost entirely composed of α-phase. The temperature of deposition influences on the phase composition of PbO2 coatings. Thus, an increase in temperature leads to the growth of β-phase content in the coating. At the same time, the rising of temperature also increases the peaks intensity on the diffractogramm. The latter, probably, indicates an increase in the crystal size. The differences in the phase composition of obtained materials have been also detected as changing pH of the solution. Thus, pH growth leads to an increase in the β-phase content in the coating. The electrocrystallization of PbO2 begins with the formation of a monolayer on the electrode surface, and then the formation and growth of three-dimensional nuclei take place. The simultaneous formation of α- and β-phases results in the presence of two linear areas on the plot of (j-j1)1/3 vs. time for the progressive growth of crystals. The formation of one phase is noticeably lagged behind the other. At layer-by-layer crystallization and significant lagging of one of phases, the ingesting of growing centres of one phase by another may occur. The type of lagging phase depends on the nature of electrolyte: it is β-phase for the nitrate bath, and α-phase for the methanesulfonate one.

47-51

Authors: I.L. Kovalenko

The paper discusses the features of sensitization of non-TNT energy condensed emulsion systems that are used to break rocks in underground conditions. Sensitization is realized by filling emulsion with oxygen microbubbles when administered gas generating additive based on hydrogen peroxide solutions. The influence of the nature of acidity regulator on the degree and rate of the emulsion gas filling has been investigated. It is shown that the use of sodium hydroxide in the composition of the dispersed phase leads to the formation of gas inclusions with size of 300-500 microns in the emulsion that reduces the stability and sensitivity of system. It is established that the combined use of sodium hydroxide (0.7-1.5% (weight) in the dispersed phase) and sodium tetraborate (0.3-0.5% (weight) in the dispersion medium) provides obtaining the energy condensed systems with an average diameter of gas inclusions of 50-100 microns. The total rate of gas generation is 25-30% (weight) for 30 min. The gas generation process can be described by the kinetic equation of the first order and is characterized by the rate constant k = 1.2∙10-3 min-1.

59-68

Authors: S.N. Kuzmenko, N.Ya. Kuzmenko, O.V. Skrynnik

The most serious deficiency of wood is its inclination to adsorb water. To prevent this, the application of tetrabutyle ester of ortotitanic acid as well as the products of their hydrolytic condensation as water repellents has proposed in the present work. The obtained results indicate that imparting the water-repellent properties is connected with the interaction of reactive butoxy groups of tetrabutyle esters of ortotitanic acid with hydroxyl groups of the unit of cellulose-based materials (CBM). The hydrophobization process of CBM by these esters is complex and multistage. It occurs via the succession of a chain of the parallel and consecutive reactions of hydrolysis, condensation and interesterification, and interaction between CBM and ester, among others. As a result of these reactions, an appreciable increase in water-repellent properties and mechanical strength of the materials both at room and at higher temperatures. The obtained results allow us to recommend the tetrabutyle esters of ortotitanic acid compositions as water-repellent agents for wood and wood-based materials.

5-15

Authors: V.S. Protsenko

Similarity theory and dimensional analysis were shown to be suitable both in electrochemical kinetics and in electrochemical engineering. The corresponding original and literature data were reviewed. The use of dimensionless groups in electrochemical mass transfer problems was described; the similarity criteria involved were summarized. Similarity theory and dimensional analysis may be successively applied for a kinetic analysis of an electrochemical reaction described both by the equations of the slow discharge theory and by the Marcus–Hush–Chidsey formalism. The corresponding dimensionless quantities (similarity criteria) were derived and approximating interrelations between them were analyzed. The results of numerical simulation of the kinetics of a two-stage electrochemical reaction with partial transfer of intermediates between the electrode surface and the bulk solution in conditions of linear nonsteady-state diffusion of reactants are analyzed with the use of dimensional analysis and similarity theory (i.e. a theory of generalized variables). Some dimensionless complexes utilized in applied electrochemistry were reviewed. The main advantages of the application of similarity theory and dimensional analysis in pure and applied electrochemistry were generalized.

19-25

Authors: М.І. Vorobyova, O.A. Pivovarov

The paper considers an opportunity and evaluates the effectiveness of using the solutions treated with low-temperature non-equilibrium contact plasma in order to intensify the dissolution of metal gold in cyanide leaching solutions. As a result of investigations, it was found that plasma-chemically treated solutions due to the presence of peroxide compounds, radicals and particles formed in water during treatment, exhibit significant oxidizing properties compared with synthetic hydrogen peroxide and gaseous oxygen which are currently used in hydrometallurgical industry as oxidizing components. Using a rotating disk technique, the effect of the basic technological parameters (the effects of rotation speed, cyanide, potassium hydroxide and hydrogen peroxide concentration, temperature, pH) on the rate of process of metal gold dissolution in plasma-chemically treated solutions, and those using synthetic hydrogen peroxide and gaseous oxygen, was found. It is shown that the dissolution of gold in all cases occurs in transient conditions, as evidenced by the calculated values of activation energies. Comparison of the values of activation energies of the gold dissolution process points to the advantage of use of plasma-chemically treated solutions over use of synthetic hydrogen peroxide and oxygen as oxidizing agents.

30-36

Authors: K.S. Burmistrov, V.N. Toropin, V.V. Ryabenko, G.N. Kremenchutskiy, A.K.Balalaev

The communication deals with the emission of the "active chlorine" from sodium N-chlorsulfonamides immobilized in the copolymer of styrene-divinylbenzene into aqueous solutions using various activators of amine type, such as ammonium chloride, KU2-8 cation exchanger in an ammonium form, aqueous ammonia, sulfaminic acid, and taurine. The highest "active chlorine" concentration of 500-900 mg/dm3 is achieved through the activation by sulfaminic acid and taurine. These activators provide the high active chlorine content due to the formation of stable compounds in the solution, viz. N-chlorotaurine and N-chlorsulfamine acid. Some of the obtained solutions (with concentration of 30 mg/dm3) are tested for antimicrobial properties. The tests are conducted on the test cultures of opportunistic pathogens taken from the funds of the Culture Museum at the Department of Microbiology, Virology, Immunology and Epidemiology at Dnepropetrovsk Medical Academy. These results confirm the high antimicrobial activity of solutions.

39-44

Authors: V.M. Kozlov, V.P. Hlyntsev, V.N. Timoshenko

Electrolytic deposition of metals is carried out from the electrolytes containing surface-active additives in order to improve the functional properties of deposits. Therefore it is important to study in detail the influence of surface-active additives on all stages of metals deposition on cathode, including the stage of noncoherent nucleation. On the basis of the atomic theory of nucleation, a theoretical analysis of noncoherent nucleation in the presence of adsorbed foreign particles was performed. The influence of the adsorption factors on the probability of the formation of high-angle boundaries in the electrodeposits is considered. Based on the obtained data, a model of the formation of two different types of polycrystalline structure electrodeposits is created. It is established that the transition from a polycrystalline structure fiber type to the structure of isotropic type must occur when exceeding a certain value for the filling degree of the adsorbate cathode surface. Theoretical results are confirmed by experimental structural data on electrodeposition of copper obtained from the electrolyte containing additive thiourea with the different concentration.

49-52

Authors: S.V. Kravchenko

Some researchers have reported that anhydride of bicycle [2.2.1] hept-5-en-endo, endo-2,3-dicarboxylic acid reacted with mixture of hydroxylamine hydrochloride and sodium methylate yielding 1,4-dioxo-5,8-endomethylene-3,8,9,10-tetrahydrobenz-2,3-oxazine. We think that this is not true. As we have found, anhydride of bicycle [2.2.1]hept-5-en-endo,endo-2,3-dicarboxylic acid reacted with hydroxylamine in the methanol solution yielding only N-hydroxyimide of bicycle[2.2.1]hept-5-en-endo,endo-2,3-dicarboxylic acid. The melting point of recrystallized N-hydroxyimide of bicycle[2.2.1]hept-5-en-endo,endo-2,3-dicarboxylic acid is 163-164 °C. It is close to the earlier reported value of 1,4-dioxo-5,8-endo-methylene-3,8,9,10-tetrahydrobenz-2,3-oxazine which is 160 °C. The structure of N-hydroxyimide of bicycle[2.2.1]hept-5-en-endo,endo-2,3-dicarboxylic acid has been established by means of NMR 1H spectroscopy, mass-spectrometry and finally by XRD study. According to the XRD data, the pyrrolidine ring in N-hydroxyimide of bicycle[2.2.1]hept-5-en-endo,endo-2,3-dicarboxylic acid has the trans orientation to the endo methylene bridge of the norbornane – the С9-С8-С3-С2 torsion angle is equal 151.04(13) degree. The length of the N-O bond is 1.3806(17) Å. The nitrogen atom has planar configuration – the sum of its bond angles is 359.37 degrees.

56-60

Authors: T.L. Rakitskaya, T.A. Kiose, L.P. Oleksenko

In the work, samples of natural tripoli from Konoplyanskoye deposit were used. Catalytic compositions were obtained by impregnation of the samples with an aqueous solution containing K2PdCl4, Cu(NO3)2, and KBr and their subsequent drying in air at 110 C till constant weight. To obtain different water contents in the samples, they were kept in a desiccator over an aqueous solution of sulfuric acid (30-35 %) for 1, 2, 3 or 4 hours. Both the initial and chemically modified tripoli samples were characterized by thermogravimetric analysis and by water vapor ad/desorption. They were also tested in the reaction of low-temperature oxidation of carbon monoxide with air oxygen. The CO oxidation degree in the steady-state regime was used as the measure of catalytic activity of the samples. It was found that the increase in water content in the natural tripoli anchored copper-palladium catalyst from 0.89 to 3.67 mmol/g was resulted in lower (by 2 %) carbon monoxide oxidation degree. Nevertheless, the catalyst provided the air purification to MPCCO (20 mg/m3). The catalyst activity drastically decreased when the water content was higher than 3.67 mmol/g. This can be caused by the multilayer adsorption of water molecules on the catalyst surface preventing access of CO molecules to its active sites. Thus, the catalyst may be recommended for air purification from CO at the ambient relative humidity.

65-70

Authors: P.I. Bashtanik, N.Ya. Kuzmenko, A.M. Igonina, Ya.I. Evtushenko, A.G. Golovan

Introduction of fillers to thermoplastics not only decreases the cost of products but favors simultaneous increasing their physical and mechanical characteristics. In this work, investigations on the modification of thermoplastics on the base of mixture of polypropylene and polyamide 6 armored by basalt fibers have been carried out. The dressing of basalt fibers by (alkoxy))acrylatacyloxy) titanates and titanoxanates allows increasing the durability at composites stretching till 68.0 MPa that will allow exploiting the products made of them for a longer term and in a wider range of loads and temperatures. The highest values of physical and mechanical characteristics of basalt plastics are reached when dressing the fiber by compounds under consideration in the range of 0.75–1.00 mas.%; simultaneously, mechanical parameters being redoubled if using tetra(acrylatacyloxy) of titanium. Further increasing the quantity of dressing substance on basalt fibers is not reasonable because it leads to a decrease in physical and mechanical characteristics of composites. The products made of the developed basalt plastics, in which simpler and cheaper raw materials are used, will be able to meet competition at applying in different mechanisms and constructions.

76-80

Authors: D.V. Girenko, K.O. Demianchuk

In the paper it was considered the influence of various factors on the synthesis of sodium hypochlorite for human and veterinary medicine in undivided flow-type electrochemical cells with the steel X12CrNiTi18-9 cathode (60 cm2) and oxide composite Ti/SnO2-IrO2 anode (60 cm2). For any number of series-connected cells the volume rate of electrolyte flow has almost no effect on the concentration ratio of [NaClO]/[NaClO3]. The increase of NaCl concentrations from 9 to 27 g/L results in a slight increase in the hypochlorite content and more substantially in sodium chlorate content. Current reduction leads to a significant increase of [NaClO]/[NaClO3] ratio and this effect is the stronger the less number of cells are involved. At a current load of 2.0 A and the initial concentration of sodium chloride 9 g/L one electrolytic cell, which comprises two series-connected flow cells, allows to obtain 8.0 L/h of the solution with pH=8.5, containing 530 mg/L NaClO and 5,3 mg/L NaClO3. The increase of the volume rate of electrolyte flow up to 14 L/h gives solution containing 300 mg/L NaClO and and not more than 3 mg/L NaClO3.

84-88

Authors: K.I. Kukuruzenko, A.Y. Nikiforova, O.O. Pasenko, O.V. Kozhura

The processes of vanadium acid leaching as well as vanadium thermo-hydrolytic precipitation were considered for the case of the treatment of spent SVD catalysts for the manufacture of sulfuric acid. It was established that the solubility of vanadium at 200C in a salt solutions which are formed by leaching increases substantially with an increase in the concentrations of sulfuric acid. Under the conditions of the thermo-hydrolytic precipitation at 90-950С, the solubility of vanadium decreases; the dependence of the vanadium solubility on the sulfuric acid concentration becomes less pronounced. The difference in vanadium solubility at low and high temperatures for the SVD catalysts allows recovering solutions to the leaching stage after the precipitation. It is possible to carry out the precipitation stage without adjusting the acidity level. The maximum difference in vanadium solubility between the leaching and thermo-hydrolytic stages is achieved at the excess H2SO4 concentration of 50 g/L. The filtrates of these operations were cyclically used during leaching and precipitation, vanadium concentrates being obtained which contain a minimal amount of contaminants. In addition, high technological parameters remain at the filtration step. The achieved level of vanadium extraction is 85-90% when solutions are used cyclically. The content of vanadium pentoxide in concentrate is equal to 90%.

95-102

Authors: I.S. Samchileev, A.E. Kirpikina, N.V. Nikolenko, A.O. Kostynyuk

In the paper, some aspects of the conversion of used iron-molybdenum catalysts are considered. The main goal of the processing of the used iron-molybdenum catalysts is an extraction of molybdenum as the most valuable component. It is of interest to investigate the possibility of its repartition by treatment with sulfuric acid, wherein molybdenum is in the form of a precipitate of hydrated oxide, and the iron ions pass into solution. Kinetic studies were carried out in a loop reactor with a model stationary solid phase. Spent catalyst simulated granular ferric molybdate with a molar ratio Mo/Fe ~1.5 and a grain size of 1-3 mm. Thermodynamic analysis showed that the decomposition of iron molybdate by sulfuric acid can be used provided the concentration of sulfate ions is maintained at not less than 0.8 mol/L, and the acidity of the solution should be not more than 0.1 mol/L. These conclusions were confirmed experimentally. If a flow rate of the solution was not less than 0.04 m/s, the leaching process was limited by the iron ions diffusion through a layer of chemical reaction product. It is concluded that the use of acid solutions with concentrations above 10% as well as an increase in temperature is impractical because of the increased solubility of molybdenum trioxide. It was shown that the main factors of the process decomposition by sulfuric acid are molybdate catalyst particle size and concentration of the leaching solution.