Издательство СО РАН

Издательство СО РАН

Адрес Издательства СО РАН: Россия, 630090, а/я 187
Новосибирск, Морской пр., 2

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Яндекс.Метрика

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Химия в интересах устойчивого развития

2003 год, номер 1

1.
Предисловие


Страницы: 1-2



2.
The Potential of Structured Reactors in Process Intensification

JACOB A. MOULIJN, ANDRZEJ STANKEWICZ and FREEK KAPTEIJN
Reactor & Catalysis Engineering, DelftChemTech, Faculty of Applied Sciences,
Delft University of Technology, Julianalaan 136, 2628 BL, Delft (The Netherlands) E-mail: j.a.moulijn@tnw.tudelft.nl
Страницы: 3-10

Аннотация >>
Structured catalytic reactors have a large potential in Process Intensification. In many respects they outperform conventional reactors such as packed-bed and slurry reactors, both for gas and for gas – liquid systems. The most important structured reactors are based on gauzes, foams, and monoliths. In general, monoliths are the most satisfactory structured reactors. In gas-phase applications they are often preferred due to their favourable properties with respect to selectivity, pressure drop, and robustness. Their millisecond characteristics have potential in syngas production and selective conversions into valuable products. In gas-liquid applications they exhibit high rates, high selectivity (for serial kinetics), and they operate close to pluγ-flow behaviour. They are compact reactors with excellent performance in activity and selectivity. They allow co- as well as counter-current operation at common industrial conditions and can be used in multifunctional reactors, e. g. catalytic distillation. The use of a structured reactor allows the decoupling of intrinsic reaction kinetics, transport phenomena, and hydrodynamics. In this way these processes in a catalytic reactor can be optimised independently, giving rise to an excellent reactor performance. Structured catalysts and reactors will play a major role in Process Intensification.


3.
Carbohydrates as Chemical Feedstock

Herman van Bekkum1 and Arie C. Besemer2
1Delft University of Technology, Julianalaan 136, 2628 BL Delft (The Netherlands)
2SCA Hygiene Products, PO Box 360, 3700 AJ Zeist (The Netherlands), E-mail: H.vanBekkum@stm.tudelft.nl
Страницы: 11-22

Аннотация >>
With an increasing population, up to 9 billion, and oil as well as gas stocks being finite, we should reconsider sustainable raw materials, as provided annually by plants and trees and covered by the collective term biomass, as chemical feedstock. Carbohydrates are the


4.
Silicon-Wafer Based Planar Models for Hydrotreating Catalysts

E. J. M. Hensen, L. Coulier, A. Borgna, J. A. R. van Veen and J. W. Niemantsverdriet
Schuit Institute of Catalysis, Eindhoven University of Technology,
P.O. Box 513, 5600 MB Eindhoven (The Netherlands), E-mail: e.j.m.hensen@tue.nl
Страницы: 23-30

Аннотация >>
In the present study the use of planar silicon-based models for hydro-treating catalysts is discussed. The specific flat nature makes these models amenable to high resolution surface-sensitive techniques such as XPS. The additional possibility to measure the activity of such model catalysts in thiophene hydrodesulfurization provides a powerful tool to determine structure-activity relations. Here, we study the effect of chelating agents (NTA and EDTA) on the sulfidation order of NiMo catalysts. The XPS results clearly show that the use of these chelating agents retards the sulfidation of Ni with respect to Mo. Especially, EDTA is effective by postponing Ni sulfidation after Mo is completely sulfided. The latter catalyst also displays the highest activity which is attributed to the highest amount of `Ni-Mo-S'-type phases. In essence, the results underpin the notion that such `Ni-Mo-S' phase can be formed effectively when Ni sulfidation proceeds after MoS2 has been formed. When Ni sulfides at too low temperature, inactive bulky Ni3S2 clusters are formed.


5.
Iron Clusters Occluded in Zeolite ZSM5 Micropores

E. J. M. Hensen, Q. Zhu, P. C. M. M. Magusin and R. A. van Santen
Schuit Institute of Catalysis, Laboratory of Inorganic Chemistry and Catalysis,
Eindhoven University of Technology,
P.O. Box 513, 5600 MB, Eindhoven (The Netherlands), E-mail: e.j.m.hensen@tue.nl
Страницы: 31-36

Аннотация >>
The effect of high temperature calcination and steaming on iron-containing zeolite was studied. Iron was introduced by sublimation of FeCl3. FTIR measurements clearly show the disappearance of Broensted acid sites upon such treatments. This is attributed to a reaction between small occluded Fe oxide clusters obtained after initial low temperature calcination and the zeolite protons to give cationic Fe species compensating the negative zeolite charge. High temperature calcination and especially steaming considerably increase the catalyst activity in nitrous oxide decomposition. The two treated catalysts exhibit a higher apparent activation energy than the original sample. This high apparent activation energy is compensated by a high pre-exponential factor. In Fe/ZSM5 the activity mainly derives from small Fe oxide clusters, while upon treatment more active cationic species are generated. The kinetic parameters point to a stronger Fe–O bond for the latter case.


6.
Modeling of Heat and Mass Transport in Wall-Cooled Tubular Reactors

G. W. Koning, A. E. Kronberg and W. P. M. van Swaaij
University of Twente, Faculty of Chemical Technology,
P.O. Box 217, 7500 AE Enschede (The Netherlands), E-mail: gwkoning@hetnet.nl
Страницы: 37-46

Аннотация >>
Heat transfer experiments with and without chemical reaction were performed in a wall-cooled tubular reactor. The oxidation of carbon monoxide over a CuO/γ-alumina catalyst was used as a model reaction. A two-dimensional heterogeneous reactor model was used for calculation of the temperature and concentration profiles inside the packing. The experiments were performed at Re between 200 and 1400, reactor pressures of 3, 5.9 and 8 bar, wall temperatures of 156, 180 and 200 °C and CO inlet concentrations ranging from 0.1 to 1.5% vol. The obtained data show that a radial distribution of the axial fluid velocity should be taken into account to reconcile the effective heat transport parameters obtained from experiments with and without reaction.


7.
The Role of NHn Species in Oscillation Phenomena in the NO + H2 Reaction on Noble Metal Surfaces: Semi-Empirical Calculations

A. R. Cholach1, N. N. Bulgakov1 and B. E. Nieuwenhuys2
1G. K. Boreskov Institute of Catalysis, Siberian Branch of the Russian Academy of Sciences,
Pr. Akademika Lavrentyeva 5, Novosibirsk 630090 (Russia), E-mail: cholach@catalysis.nsk.su
2Leiden Institute of Chemistry, P. O. Box 9502, 2300 RA Leiden (The Netherlands)
Страницы: 47-54

Аннотация >>
The semi-empirical Method of Interacting Bonds was used in the present work to clarify the mechanism of the title process. Various single crystal planes of Pt, Rh, Ir, Fe, and Re were examined with respect to the stability of the adsorbed NHn species (n = 0, 1, 2, 3); to the reactivity of NHn (n = 0, 1, 2) species towards adsorbed hydrogen atoms; and to the possibility of proceeding the combination reactions between two NH or two NH2 particles resulting in the formation of gaseous H2 and N2 molecules. All the surfaces studied were found to form readily the stable NH species. The principal difference between Pt, Rh, Ir single crystal planes, on which the reaction exhibits rate oscillations, and Fe, Re surfaces, which do not show an oscillatory behaviour, is that the combination reaction of NH species can easily proceed in the former case, but this reaction is not allowed thermodynamically on the latter surfaces. This result is consistent with an earlier suggested mechanism for the oscillatory behaviour that attributes the surface wave propagation to the intermediate formation of NH species. Stable NH2 species can be formed on Re and Fe surfaces, whereas the noble metal surfaces can form weakly stable NH2 particles at the very edge of their existence region. The combination reaction between two NH2 species is endothermic in all cases.


8.
The Conjugate Electron Excitation in a Substrate – Adsorbate System

A. R. Cholach and V. M. Tapilin
G. K. Boreskov Institute of Catalysis, Siberian Branch of the Russian Academy of Sciences,
Pr. Akademika Lavrentyeva 5, Novosibirsk 630090 (Russia), E-mail: cholach@catalysis.nsk.su
Страницы: 55-62

Аннотация >>
The electronic peculiarities of the Pt(100)–(1 x 1) surface effected by various adsorbates and interactions in adsorbed layer were studied by the Disappearance Potential Spectroscopy (DAPS). Two types of features were observed in DAPS spectra. The first type corresponds to an ordinary threshold excitation of platinum core electron to an available vacant state. These features are attributed to the substrate properties, and their positions are in good agreement with corresponding Local Density of States (LDOS) calculations. The second type of features new way of primary electron energy consumption – the conjugate electron excitation, which includes the above threshold transition of the substrate core electron, accompanied by excitation of the valence electron of adsorbed species to vacuum level. Positions of the respective spectral satellites are close to corresponding ionization potentials of a given species in adsorbed layer. Our experimental data show altogether more than 10 satellites, providing the evidence of reliability of the conjugate electron excitation process. The present results as a whole experimentally demonstrate the substantial unity of the substrate and adsorbate electronic structures.


9.
Weakly Stable Dynamics in a Three-Dimensional Kinetic Model of Catalytic Hydrogen Oxidation

G. A. Chumakov1 and N. A. Chumakova2
1S. L. Sobolev Institute of Mathematics, Siberian Branch of the Russian Academy of Sciences,
Pr. Akademika Koptyuga 4, Novosibirsk 630090 (Russia), E-mail: chumakov@math.nsc.ru
2G. K. Boreskov Institute of Catalysis, Siberian Branch of the Russian Academy of Sciences,
Pr. Akademika Lavrentyeva 5, Novosibirsk 630090 (Russia), E-mail: chum@catalysis.nsk.su
Страницы: 63-66

Аннотация >>
Some new results concerning complex dynamics in a kinetic model of heterogeneous hydrogen oxidation over metallic catalysts are presented. Relaxation oscillations with a high sensitive dependence on the initial conditions arise in the three-variable system with fast, intermediate and slow variables due to existence of the canard cycles that occur in the one-parameter family of two-variable subsystems. A key feature of the weakly stable dynamics appearance will be successive period doubling bifurcations in which the system behaviour becomes progressively more complex until the attractor appears.


10.
Mechanism for CO Oxidation and Oscillatory Reactions on Pd Tip and Pd(110) Surfaces: FEM, TPR, XPS Studies

V. V. Gorodetskii1, A. V. Matveev1, A. V. Kalinkin1 and B. E. Nieuwenhuys2
1G. K. Boreskov Institute of Catalysis, Siberian Branch of the Russian Academy of Sciences,
Pr. Akademika Lavrentyeva 5, Novosibirsk 630090 (Russia), E-mail: gorodetsk@catalysis.nsk.su
2Leiden Institute of Chemistry, P. O. Box 9502, 2300 RA Leiden (The Netherlands)
Страницы: 67-74

Аннотация >>
Detailed studies of the coadsorption of oxygen and carbon monoxide, hysteresis phenomena and oscillatory reaction of CO oxidation on Pd(110) and Pd tip surfaces have been carried out with the molecular beam (MB), field electron microscope (FEM), temperature programmed reaction (TPR) and X-ray photoelectron spectroscopy (XPS). It has been found that the occurrence of kinetic oscillations over Pd surfaces is associated with periodic formation and depletion of subsurface oxygen (Osub). Transient kinetic experiments show that CO does not react chemically with subsurface oxygen to form CO2 below 300 K. It has been found that CO does react with an atomic Oads/Osub state beginning at temperature ~150 K. Analysis of Pd tip surface with a local resolution of ~20 Å shows the availability of a sharp boundary between the mobile COads and Oads fronts.


11.
Manganese Oxide Monolith Catalysts Modified by Fe and Cu for High-Temperature Ammonia Decomposition and H2S Removal

Z. R. Ismagilov1, S. A. Yashnik1, N. V. Shikina1, I. P. Andrievskaya1, S. R. Khairulin1, V. A. Ushakov1, I. A. Ovsyannikova1, J. A. Moulijn2 and I. V. Babich2
1G. K. Boreskov Institute of Catalysis, Siberian Branch of the Russian Academy of Sciences,
Pr. Akademika Lavrentyeva 5, Novosibirsk 630090 (Russia), E-mail: zri@catalysis.nsk.su
2Delft University of Technology,
136 Julianalaan 2628 BL Delft (The Netherlands), E-mail: J.A.Moulijn@tnw.tudelft.nl
Страницы: 75-88

Аннотация >>
Monolith sorbents/catalysts that have potential in simultaneous removal of H2S and NH3 from hot fuel gas were developed. Preparation methodology and composition of supported honeycomb sorbents/catalysts, based on manganese oxides modified by Fe and Cu oxides, have been optimized. Impregnated and washcoated monolith catalysts were tested in ammonia high temperature decomposition and H2S sorption. Approaches for improving the thermal stability and catalytic activity under reaction conditions are described.


12.
Development of Fe2O3-Based Catalysts of Different Geometries for Environmental Catalysis

L. A. Isupova, V. A. Sadykov, S. V. Tsybulya, G. S. Litvak, G. N. Kryukova, E. B. Burgina and A.V. Golovin
G. K. Boreskov Institute of Catalysis, Siberian Branch of the Russian Academy of Sciences,
Pr. Akademika Lavrentyeva 5, Novosibirsk 630090 (Russia), E-mail: isupova@catalysis.nsk.su
Страницы: 89-100

Аннотация >>
X-ray, TA, IRS, TEM and BET techniques were used to study the effect of mechanical treatment in a centrifugal planetary ball mill EI 2´150 and in a continuously operating vibration ball mill VCM-25 on physicochemical properties of powdered iron oxide of different prehistory, as well as on the properties of produced granulated supports and catalysts. The influence of structure-forming additives and electrolyte was discussed. The influence of the method used for introduction of the active component on the catalyst properties for complete oxidation of butane and CO was established.


13.
Theoretical Investigation of the Mechanism of Methanol Carbonylation Catalyzed by Dicarbonyldiiodorhodium Complex

E. A. Ivanova,1 V. A. Nasluzov,1 A. I. Rubaylo1and N. Rцsch2
1Institute of Chemistry and Chemical Technology, Siberian Branch of the Russian Academy of Sciences,
Ul. K. Marxa 42, Krasnoyarsk 660049 (Russia),
E-mail: ei@krsk.info
2Institut fur Physikalische und Theoretische Chemie, Technische Universitat Munchen,
85747 Garching (Germany), E-mail: roesch@ch.tum.de
Страницы: 101-108

Аннотация >>
The entire potential energy profile of the catalytic cycle of methanol carbonylation catalyzed by [Rh(CO)2I2] complex was explored computationally using a gradient-corrected density functional method and polarizable continuum model for accounting of solvent effects. For this purpose, the relative energies of the intermediates and transition states for CH3I oxidative addition, the CO migratory insertion and the CH3COI reductive elimination were estimated. Based on calculated energies the lowest-energy reaction path was deduced to be determined by the cis-dicarbonyl species in spite the trans-conformers of 6-coordinated intermediates [RhCH3(CO)2I3] and [Rh(CH3CO)(CO)2I3] were found to be more stable. The explanation is the lower activation barriers for transformation of cis-conformers to products. The activation barriers for oxidative addition, CO migratory insertion and reductive elimination steps were calculated to be at 135, 40 and 75 kJ/mol, respectively. The first step was found to be the rate-determining. The accounting for solvent effects makes the energy profile smoother and more consistent with experimental reaction profile.


14.
Investigation of Heterogeneous Catalytic Reactions by the in situ 1H NMR Microimaging

I. V. Koptyug1, A. V. Kulikov2, A. A. Lysova1,2,3, V. A. Kirillov2, V. N. Parmon2 and R. Z. Sagdeev1
1International Tomography Center, Siberian Branch of the Russian Academy of Sciences,
Ul. Institutskaya 3A, Novosibirsk 630090 (Russia),
E-mail: koptyug@tomo.nsc.ru
2G. K. Boreskov Institute of Catalysis, Siberan Branch of the Russian Academy of Sciences,
Pr. Akademika Lavrentyeva 5, Novosibirsk 630090 (Russia), 3Novosibirsk State University,
Ul. Pirogova 2, Novosibirsk 630090 (Russia)
Страницы: 109-116

Аннотация >>
The NMR microimaging is used for the first time as an in situ method to study two model three-phase heterogeneous catalytic reactions with strong exothermicity. It is shown for the α-methylstyrene hydrogenation that in the course of the reaction, two domains coexist inside the catalyst grain which differ in the liquid phase content. The 2D maps of the liquid distribution in the course of this reaction are obtained. The reaction of the hydrogen peroxide decomposition at moderate activity of the catalyst and the H2O2 concentrations in the range of (0.03–3) M is shown to occur only in a thin layer near the catalyst surface. The influence of the medium inhomogeneity on the behaviour of the Belousov – Zhabotinsky chemical oscillator reaction is investigated as well.


15.
Bioepoxidation of Propylene by Non-Growing Cells of Rhodococcus sp.

G. A. Kovalenko, I. B. Ivshina, E. V. Kuznetsova, I. S. Andreeva and A. V. Simakov
G. K. Boreskov Institute of Catalysis, Siberian Branch of the Russian Academy of Sciences,
Pr. Akademika Lavrentyeva 5, Novosibirsk 630090 (Russia), E-mail: galina@catalysis.nsk.su
Страницы: 117-122

Аннотация >>
The biotechnological potential of Rhodococcus sp. bacteria for direct selective bioepoxidation of propylene to propylene oxide has been investigated. The kinetics of accumulation of propylene oxide in suspensions of the non-growing bacterial cells has been studied. The effect of propylene oxide produced on biocatalytic activity of Rhodococcus cells has been investigated. The study of bacteria adsorption on various ñarbon-containing inorganic supports has been started to develop efficient adsorbents for Rhodococcus immobilization.


16.
Relationship between Surface Properties of Modified Titanooxides and Their Catalytic Performance in the Reaction of Ethylene Glycol Ethoxylation

R. A. Kozlovskiy1, V. F. Shvets1, A. V. Koustov1, L. E. Kitaev2, V. V. Yushchenko2, V. V. Kriventsov3, D. I. Kochubey3 and M. V. Tsodikov4
1D. I. Mendeleev University of Chemical Technology of Russia,
Miusskaya Pl. 9, Moscow 125047 (Russia), E-mail: kra@muctr.edu.ru
2M. V. Lomonosov Moscow State University, Chemical Department,
Vorobyovy Gory, Moscow 119899 (Russia),
3G. K. Boreskov Institute of Catalysis, Siberian Branch of the Russian Academy of Sciences,
Pr. Akademika Lavrentyeva 5, Novosibirsk 630090 (Russia),
4A. V. Topchiev Institute of Petrochemical Synthesis, the Russian Academy of Sciences,
Leninskii prospect 29, Moscow 117912 (Russia)
Страницы: 123-130

Аннотация >>
Relationship of structure and surface properties of modified titanium dioxides, prepared by alkoxide method using derivatives of phosphoric acid as precursors, with their catalytic performance in the reaction of ethylene glycol ethoxylation was investigated. It was found, that such catalysts are mono-phase, nanocluster ones with anatase structure, and have uniform narrow pore distribution. Catalysts prepared using the amidophosphite precursors provide high catalytic activity due to the high surface acidity, and high selectivity of diethylene glycol formation due to the "sieve effect" and concert acid-base mechanism of ethylene oxide addition.


17.
Reduction of Coke Formation on Pt–Re Gasoline Reforming Catalysts

A. V. Kravtsov, E. D. Ivanchina, L. V. Krupenya and S. A. Galushin
Tomsk Polytechnical University, Leninskiy pr. 30, Tomsk 634034 (Russia), E-mail: master79@mail.ru
Страницы: 131-134

Аннотация >>
The catalytic activity fluctuations upset the equilibrium in reactions of the hydrogenation of carbon depositions and causes increased coke formation. We propose a method of estimation of the Pt–Re catalysts activity, which allows keeping track of the activity enhancement, and hence provides prolongation of the catalyst service cycle by 20–30 %. The method is based on keeping the catalytic activity at an optimum level using the developed computer system.


18.
The Influence of Inert Impurities on the Catalyst Lifetime and Properties of Nanofibrous Carbon Produced by Utilization of Diluted Hydrocarbon Gases

G. G. Kuvshinov, D. G. Kuvshinov and A. M. Glushenkov
G. K. Boreskov Institute of Catalysis, Siberian Branch of the Russian Academy of Sciences,
Pr. Akademika Lavrentyeva 5, Novosibirsk 630090 (Russia), E-mail: ggk@catalysis.nsk.su
Страницы: 135-140

Аннотация >>
Experimental studies were focused on the feasibility of utilization of hydrocarbons diluted with inert gases (such as associated oil gases) during the synthesis of nanofibrous carbon. The carbon yield and catalyst lifetime were studied regarding the initial reaction mixture parameters. Varying the composition of the initial gas mixture, it is possible to control textural characteristics of the resulting carbon product.


19.
Environmentally Friendly Catalytic Production of Cellulose by Abies Wood Delignification in "Acetic Acid – Hydrogen Peroxide – Water" Media

S. A. Kuznetsova1, V. G. Danilov1, B. N. Kuznetsov1, O. V. Yatsenkova1, N. B. Alexandrova2, V. K. Shambasov1 and N. I. Pavlenko1
1Institute of Chemistry and Chemical Technology,
Siberian Branch of the Russian Academy of Sciences,
Ul. K. Marxa 42, Krasnoyarsk 660049 (Russia)
2Krasnoyarsk State University, Pr. Svobodny 79, Krasnoyarsk 660062 (Russia), E-mail: ksa@icct.ru
Страницы: 141-148

Аннотация >>
The paper concerns the environmentally benign method of catalytic cellulose production by wood delignification over various catalysts using sulfur-free reagents – acetic acid and hydrogen peroxide. The optimum operation conditions (temperature and time of the process, H2O2/CH3COOH and liquor/wood ratios) of abies wood delignification using sulphuric acid as reagent and TiO2 as catalyst which allow reaching the acceptable yields of cellulosic product with high content of cellulose were selected.


20.
The Influence of Porous Structure and Acid-Base Properties of Active Aluminium Oxide on its Catalytic Activity in the Dehydratation of α-Phenylethanol

A. A. Lamberov1, R. G. Romanova2, I. G. Shmelev2, E. Yu. Sitnikova1 and S. R. Egorova2
1Kazan&#39 Chemical Research Institute,
Sibirskiy trakt 27, Kazan&#39 420029 (Russia), E-mail: segorova@rambler.ru
2Kazan&#39 State Technological University,
Ul. K. Marxa 68, Kazan&#39 420015 (Russia), E-mail: rrg@kstu.ru
Страницы: 149-154

Аннотация >>
The influence of porous structure and surface acid-base properties of γ-Al2O3, prepared by means of aluminate-nitrate and electrochemical methods, on its catalytic activity in the process of α-phenylethanol dehydratation has been studied. It was shown, that activity of catalyst depends on the predominating diameter of pores. The methods of changing the porous structure of γ-Al2O3 with the purpose of increasing its catalytic activity were considered. Thermal or hydrothermal treatment of active aluminium oxide allows to obtain the porous structure, providing the maximum activity of catalyst in the process of α-phenylethanol dehydratation. It was also shown, that conversion of α-phenylethanol and selectivity are determined by the surface concentrations of Broensted and Lewis acid centres. The rate of catalyst deactivation (coke formation) is proportional to the concentration of base centres. The influence of content of sodium cations on the acid-base properties and activity of catalyst was determined. Purification of used γ-Al2O3 from sodium cations results in the catalyst, having the maximum catalytic activity.


21.
XPS Study of Metal-Support Interaction in Ru/MgO Catalyst for Low-Temperature Ammonia Synthesis

Yu. V. LARICHEV1, 2, B. L. MOROZ2, I. P. PROSVIRIN2, V. A. LIKHOLOBOV1, 2 and V. I. BUKHTIYAROV2
1Novosibirsk State University,
Ul. Pirogova 2, Novosibirsk 630090 (Russia), E-mail: prsv@catalysis.nsk.su
2 G. K. Boreskov Institute of Catalysis, Siberian Branch of the Russian Academy of Sciences,
Pr. Akademika Lavrentyeva 5, Novosibirsk 630090 (Russia), E-mail: moroz@catalysis.nsk.su
Страницы: 155-160

Аннотация >>
The catalytic system Ru/MgO has been characterized by TEM and XPS in the Ru 3d, Cl 2p and O1s regions. It was shown, that the treatment of the sample with H2 at 450 °Ñ leads to reduction of supported Ru (III, IV) chloride complexes to Ru metal crystallites of 2–5 nm in size (the surface atomic ratio Ru : Cl of reduced sample is 6.2). The shift of Ru 3d peak (279.5 eV) to lower bond energy (BE) found for Ru/MgO sample as compared with bulk Ru metal (280.2 eV) is proved to be due to the differential charging effect. The value of this effect was estimated by a comparison of the valence band spectrum of supported Ru particles with that of bulk Ru. Taking the differential charging into account, the "true" value BE of Ru 3d5/2 (280.5 eV) was determined. The shift of Ru 3d peak towards the higher BE values may indicate the electron-withdrawing effect of MgO surface to supported Ru particles.


22.
Oxidation Catalyst for Gas Oxygen Sensors

G. D. MALCHIKOV1, N. I. TIMOFEEV2, V. I. BOGDANOV2, E. N. TUPIKOVA1 and N. E. GORYAINOVA1
1S. P. Korolev Samara State Aerospace University,
Moskovskoye shosse 34a, Samara 443086 (Russia)
2Yekaterinburg Non-Ferrous Metals Processing Plant,
Pr. Lenina 8, Yekaterinburg 620014 (Russia), E-mail: chem@ssau.ru
Страницы: 161-166

Аннотация >>
The metal (stainless steel) porous "metal-rubber" monolith-supported Pt, Pd, Pt–Rh and Pd–Rh catalysts are tested in the process of complete oxidation of hydrocarbons. At stoichiometric and higher oxygen content practically complete conversion of model hydrocarbon occurred at 380 °C on all catalysts. At these temperatures the catalysts work in outward diffusive area. At the oxidant to fuel ratio lower than stoichiometric the maximal conversion of hydrocarbon is reached at lower temperatures (250 °Ñ). In complete hydrocarbon oxidation steady work of platinum catalyst is possible, if the content of sulphur in hydrocarbon does not exceed 0.3 % mass. These catalysts may be used for preparing a gas sample in oxygen sensors.


23.
Mo/ZSM-5 Catalysts for Methane Aromatization. Study of the Mo Precursor Species in Impregnation Solution of Ammonium Heptamolybdate

E. V. Matus, L. T. Tsykoza, Z. R. Ismagilov and V. V. Kuznetsov
G. K. Boreskov Institute of Catalysis, Siberian Branch of the Russian Academy of Sciences,
Pr. Academika Lavrentyeva 5, Novosibirsk 630090 (Russia), E-mail:zri@catalysis.nsk.su
Страницы: 167-172

Аннотация >>
A change in the ratio between monomeric and polymeric molybdenum species regarding the concentration and pH of the impregnation solutions will probably make a significant effect on the nature and number of active sites of Mo/ZSM-5 catalysts. To provide the control of molybdenum species in solutions, we have studied the dependence of structure of molybdenum species in the initial impregnation solutions of ammonium heptamolybdate on the concentration and pH of these solutions (from electron absorption spectra). When the concentration of solutions is low or pH increases, there are no polymeric molybdenum species. Besides, there is a region where monomeric and polymeric species exist at a time. At higher concentrations or when pH decreases, monomeric species transform almost completely into polymeric species.


24.
Manifestation of the Adsorbed CO Diffusion Anisotropy Caused by the Structure Properties of the Pd(110) – (1ґ2) Surface on the Oscillatory Behaviour during CO Oxidation Reaction – Monte-Carlo Model

A. V. Matveev, E. I. Latkin, V. I. Elokhin and V. V. Gorodetskii
G. K. Boreskov Institute of Catalysis, Siberian Branch of the Russian Academy of Sciences,
Pr. Akademika Lavrentyeva 5, Novosibirsk 630090 (Russia), E-mail: elokhin@catalysis.nsk.su
Страницы: 173-180

Аннотация >>
The modelling of self-oscillations and surface autowaves in CO oxidation reaction over Pd(110) has been carried out by means of the Monte-Carlo technique. The synchronous oscillations of the reaction rate and surface coverages are exhibited within the range of the suggested model parameters (under the conditions very close to the experimental observations). The dependencies of the simulation results on the lattice size and on the diffusion intensity have been studied. It has been established that the adsorbed CO diffusion anisotropy does not influence the oscillation kinetics but leads to the appearance of the propagating reaction fronts on the palladium surface elliptically stretched along the [110] direction in close agreement with the known experimental data.


25.
Influence of Oxygen Adsorption on Surface Explosion Phenomena in the NO + CO/Pd(110) System

A. V. Matveev, A. A. Sametova, N. N. Bulgakov and V. V. Gorodetskii
G. K. Boreskov Institute of Catalysis, Siberian Branch of the Russian Academy of Sciences,
Pr. Akademika Lavrentyeva 5, Novosibirsk 630090 (Russia), E-mail: matveev@catalysis.nsk.su
Страницы: 181-188

Аннотация >>
In the present work adsorption of NO and coadsorption of NO, CO and O2 has been investigated by means of thermal desorption spectroscopy (TDS) and temperature programmed reaction (TPR). Influence of adsorbed oxygen on morphology of Pd-nanoparticles as well as Pd(110) plane was studied by the theoretical method of interacting bonds (MIB). It has been shown that adsorption of atomic oxygen induces the morphology changes of Pd-nanocrystals and Pd(110) plane. By analysis of TPR spectra of desorbing N2 and CO2 for different NOads + COads coverages, we suggest an autocatalytic reaction in an "explosive" way. The addition of oxygen was found to inhibit the process of NO dissociation. Exposure of NO and CO on oxygen pre-adsorbed layer results in appearing of low-temperature peak of CO2 in TPR spectra at 265 K.


26.
CO-Free Methyl Formate from Methanol: the Control of the Selectivity of the Process on Cu-Based Catalysts

T. P. Minyukova, N. V. Shtertser, L. P. Davydova, I. I. Simentsova, A. V. Khasin and T. M. Yurieva
G. K. Boreskov Institute of Catalysis, Siberian Branch of the Russian Academy of Sciences,
Pr. Akademika Lavrentyeva 5, Novosibirsk 630090 (Russia), E-mail: min@catalysis.nsk.su
Страницы: 189-196

Аннотация >>
The influence of the structure and composition of precursor (which is used as support after treatment) and the structure of copper particles formed in the course of activation of copper containing catalysts by hydrogen on their catalytic properties in methanol dehydrogenation and reactivity towards hydrogen adsorption has been studied. The reactivity of catalyst towards hydrogen adsorption was investigated by means of Thermal Desorption Spectroscopy (TDS). Two catalysts preserving the structure of their precursor-oxide after reduction (CuZnSi and CuCr) and having strong bonds of metal particles with the surface are characterized by hydrogen adsorption at elevated temperatures. This type of adsorption is not observed for usual unsupported metal copper and for two other catalysts Cu/SiO2 and Cu/Cr2O3. Methanol dehydrogenation proceeds via successive reactions 2CH3OH = CH3OOCH + 2H2 (I) and CH3OOCH = 2CO + 2H2 (II). The catalyst activity in reaction (II) greatly depends on the state of metal copper in the catalyst. It was assumed that catalyst activity in methyl-formate conversion to CO and H2 and, hence, the selectivity of methanol dehydrogenation in respect to methylformate at moderate methanol conversion depends on the character of interaction between metal copper particles and catalyst oxide surface, which is determined by the composition and structure of oxide precursor.


27.
Application of Polyfunctional Catalysis in Synthesis of Motor Fuels from CO2 as an Approach to the Problem of CO2 Utilization

V. M. Mysov and K. G. Ione
Scientific Engineering Centre "Zeosit", Siberian Branch of the Russian Academy of Sciences,
Pr. Akademika Lavrentyeva 5, Novosibirsk 630090 (Russia), E-mail: zeosit@batman.sm.nsc.ru
Страницы: 197-208

Аннотация >>
The development of civilization is inevitably connected with the increase of energy consumption. Nowadays the main part of energy is produced through incineration of organic fuel, the products of fuel combustion (CO2) being discharged into atmosphere. However the ecological problems impelled the world community to intensify their activity in order to decrease CO2 emission. There is a great number of known chemical reactions, both catalytic and non-catalytic, which bound CO2 chemically into various products. Specifically, the processes of hydrogen reduction of CO2 may proceed with the production of methanol, dimethyl ether (DME), methane, light hydrocarbons, or liquid motor fuels. Among these, the processes of motor fuel production on the bi-functional catalysts are most likely to be industrially applied in a large scale. The scientific and technological aspects of the processes of hydrogen reduction of carbon dioxide are considered with regard to CO2 utilization. The influences of the catalysts composition, pressure, temperature, (H2–CO2)/(CO + CO2) ratio, duration of the test run (up to 1000 h) on the activity and selectivity of the bi-functional catalysts in the synthesis of liquid motor fuels were studied. Depending on the composition of the liquid organic products, utilization of carbon in CO è CO2 comprised 70 to 90%.


28.
Model Ag/HOPG and Ag/Alumina Catalysts: STM and XPS Study

A. V. Nartova and R. I. Kvon
G. K. Boreskov Institute of Catalysis, Siberian Branch of the Russian Academy of Sciences,
Pr. Akademika Lavrentyeva 5, Novosibirsk 630090 (Russia), E-mail: nartova@catalysis.nsk.su
Страницы: 209-214

Аннотация >>
Combined XPS and ex situ STM study of the specially prepared model supported silver catalysts was performed. The drastic difference in the Ag particle shape, size distribution and spreading over the support surface were observed for alumina support as compared with pyrographite one. This effect emphasizes the important influence of the substrate nature on the morphology and surface mobility of the supported metal particles


29.
Double Stereoselection in Hydrogenation of Prochiral Dehydrocarboxylic Acids on Rh(S,S-DIODMA)2+TfOComplex in the Presence of (+)-Neomenthyldiphenylphosphine

L. О. Nindakova, О. V. Gamzikova, B. А. Shainyan and F. К. Schmidt
Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences,
Ul. Favorskogo 1, Irkutsk 664033 (Russia),
E-mail: bagrat@irioch.irk.ru
Страницы: 215-220

Аннотация >>
Enantioselective hydrogenation of α-acetamidocinnamic (AACA) and itaconic (IA) acids has been studied on rhodium complexes {[Rh(COD)2]+TfO + nMDPP}COD = 1,5-cyclooctadiene, nMDPP = (1S,2S,5R)-(+)-neomenthyldiphenylphosphine)] and {[Rh(S,S-DIODMA)2]+ TfO + nMDPP} [(S,S)-DIODMA = 4S,5S-(+)-N4,N4,N5,N5,2,2-hexamethyl-1,3-dioxolane-4,5-dimethaneamine]. Addition of nMDPP decreases the activity of the catalyst and increases the optical yield with retention of the direction of stereoselection. Optical yields for hydrogenation on {[Rh(S,S-DIODMA)2]+TfO + nMDPP} exceed those obtained on the diamine complex in the presence of Ph3P as well as those obtained on {[Rh(COD)2]+TfO + nMDPP}. The result of combined action of two ligands may be considered as manifestation of `matched' effect. Transformations of complexes have been studied by the use of 1H and 31P NMR spectroscopy. At least three complexes exist in the catalytic system, namely, diamine complex [Rh(S,S-DIODMA)2]+TfO, solvate complex [(nMDPP)2Rh(solv)2]+ TfO and diamine-phosphine complex [(nMDPP)2Rh(S,S-DIODMA)]+ TfO.


30.
Mathematical Modelling of Oscillatory Behaviour during N2O + H2 Reaction over Ir (110)

N. V. Peskov1, M. M. Slinko2, S. A. C. Carabineiro3 and B. E. Nieuwenhuys3
Страницы: 221-226

Аннотация >>
A mathematical model is presented, which simulates the oscillatory behaviour reported for the N2O+H2 reaction over Ir (110) surface. The model describes successfully the very narrow temperature range for the appearance of oscillations and the properties of oscillations including their period and the waveform. The presented model also can simulate the phase shift, between the maxima of H2O and N2 production rates, which has been detected experimentally. It is demonstrated, that this unusual phase shift between production rates of two reaction products is closely connected with the character of lateral interactions in the adlayer.


31.
Studies on the Phenol Wet Peroxide Oxidation in the Presence of Solid Catalysts

O. P. Pestunova, O. L. Ogorodnikova and V. N. Parmon
G. K. Boreskov Institute of Catalysis, Siberian Branch of the Russian Academy of Sciences,
Pr. Akademika Lavrentyeva 5, Novosibirsk 630090 (Russia), E-mail: oxanap@catalysis.nsk.su
Страницы: 227-232

Аннотация >>
The comparative study of Fe-, Mn- and Cu-oxide catalysts supported on α-Al2O3, TiO2, CeO2 and pure graphite-like porous carbon Subunit in the catalytic wet peroxide oxidation by hydrogen peroxide in a stirred batch reactor at 90 °C was performed. The Fe-containing samples supported on α-Al2O3 are sufficiently active and most stable and selective in respect to the CO2 evolution. Cu-containing catalysts are most active, Fe-containing catalysts appear to be much more stable and ecologically benign. The pure Subunit has shown an appreciable activity and highest selectivity in respect to CO2. Hydroquinone and pyrocatechol have been found in the liquid phase as intermediates of the oxidation. Kinetics of the change of the phenol, hydrogen peroxide as well as intermediates concentration has been recorded. The oxidation of phenol over Subunit is assumed to occur via a mechanism, which is different from that for the oxide catalysts.


32.
Study of Supported Catalysts Synthesized by the Use of Plasma Technique

O. Yu. Podyacheva1, N. V. Shikina1, Z. R. Ismagilov1, V. A. Ushakov1, A. I. Boronin1, N. A. Rudina1, I. A. Ovsyannikova1, S. A. Yashnik1, O. P. Solonenko2, A. A. Michal'chenko2 and H.Veringa 3
1 G. K. Boreskov Institute of Catalysis, Siberian Branch of the Russian Academy of Sciences,
Pr. Akademika Lavrentyeva 5, Novosibirsk 630090 (Russia), E-mail:pod@catalysis.nsk.su
2Institute of Theoretical and Applied Mechanics, Siberian Branch of the Russian Academy of Sciences, Ul. Institutskaya 4/1, Novosibirsk 630090 (Russia), 3ECN, P. O. Box 1, 1755 ZG Petten (The Netherlands)
Страницы: 233-238

Аннотация >>
Some prospects of application of plasma spraying technique for the synthesis of supported catalysts are demonstrated. It was shown that Mn-containing catalysts deposited on γ-Al2O3 by means of plasma spraying demonstrate superior activity in methane oxidation reaction compared with those of reference catalysts prepared via standard conventional route. Gradient alumina layer sprayed on the surface of metal supports of different geometry improves the performance characteristics of combustion catalysts on metal supports during long term operation at high temperatures. A catalytic heat-exchanging (HEX) tubular reactor for combining exothermic combustion and endothermic methane steam reforming has been developed. The methane combustion and steam reforming catalysts were synthesized on the heat-conducting metal foam support materials by application of preliminary plasma spraying in order to increase adhesive properties of the active layer. The HEX reactor with perovskite or Pt supported catalyst on Ni–Cr foam material on the external surface of the HEX tube and with Ni containing reforming catalyst on the internal Ni foam was successfully tested in methane combustion reaction combined with methane steam reforming.


33.
Promoted Iron Catalysts of Low-Temperature Methane Decomposition

T. V. Reshetenko1, L. B. Avdeeva1, Z. R. Ismagilov1, V. A. Ushakov1, A. L. Chuvilin1 and Yu. T. Pavlyukhin 2
1 G. K. Boreskov Institute of Catalysis, Siberian Branch of the Russian Academy of Sciences,
Pr. Akademika Lavrentyeva 5, Novosibirsk 630090 (Russia), E-mail: ZRI@catalysis.nsk.su
2Institute of Solid State Chemistry and Mechanochemistry, Siberian Branch of the Russian Academy of Sciences, Ul. Kutateladze 18, Novosibirsk 630128 (Russia)
Страницы: 239-248

Аннотация >>
Iron-containing catalysts promoted by nickel or cobalt were tested in methane decomposition reaction at low temperature (600–650 °C) and pressure 1 bar in order to study their catalytic properties and to produce catalytic filamentous carbon (CFC). Catalyst preparation method and composition of the catalysts were found to influence their properties. It was found, that introduction of cobalt or nickel in small amount (3–10 % mass) results in the magnification of carbon yields 2–3 times in comparison with Fe-Al2O3. Investigations of Fe-Co-Al2O3 and Fe-Ni-Al2O3 catalysts genesis were performed by Mössbauer spectroscopy, XRD, TEM. It is established that Co or Ni additives render activating influence on Fe catalysts which become apparent in decrease of the methane decomposition temperature and the formation of multiwall carbon nanotubes (MWNTs).


34.
Zirconia Pillared Clays: Synthesis, Characterization and Catalytic Properties in the NOx Selective Reduction by Hydrocarbons in the Oxygen Excess

V. A. Sadykov1,2 , T. G. Kuznetsova1, V. P. Doronin1, T. P. Sorokina1, G. M. Alikina1, D. I. Kochubei1,B. N. Novgorodov1 , E. A. Paukshtis1, V. B. Fenelonov1, V. I. Zaikovskii1, V. A. Rogov1, V. F. Anufrienko1, N. T. Vasenin1, V. A. Matyshak3, G. A. Konin3 , A. Ya. Rozovskii4, V. F. Tretyakov4, T. N. Burdeynaya4, J. R. H. Ross5 and J. P. Breen5
1G. K. Boreskov Institute of Catalysis, Siberian Branch of the Russian Academy of Sciences,
Pr. Akademika Lavrentyeva 5, Novosibirsk 630090 (Russia), E-mail: sadykov@catalysis.nsk.su
2Novosibirsk State University,
Ul. Pirogova 2, Novosibirsk 630090 (Russia)
3N. N. Semenov Institute of Chemical Physics, Russian Academy of Sciences,
Ul. Kosygina 4, Moscow 117977 (Russia)
4A. V. Topchiev Institute of Petrochemical Synthesis, Russian Academy of Sciences,
Leninskiy pr. 29, Moscow 117912 (Russia)
5University of Limerick, Technology Park, Limerick (Ireland)
Страницы: 249-262

Аннотация >>
Procedures for synthesis of thermally stable up to 750 °C zirconiα-pillared clays (ZrPC) via intercalation of a montmorillonite clay with zirconium polyoxocations modified by cations of Ce, Fe, Al, Ca, Sr, Ba, were elaborated. Optimization of the preparation procedure allowed to obtain samples with specific surface area up to 300–400 m2/g, the gallery height up to 10 Å and micropore volume up to 0.13 m2/g. Active components comprised of copper cations and/or Pt clusters were supported on ZrPC by using photoassisted deposition. The structural and surface properties of pillars and effects of mutual interaction between the nanosized zirconia particles, and metal and oxide components were elucidated by using EXAFS, UV-Vis, ESR, H2 TPR, NOx TPD and FTIRS of adsorbed CO molecules. Catalytic properties of these systems were characterized in the reactions of NOx selective reduction in the excess of oxygen by propane, propylene and decane. Strong interaction between the Pt atoms and copper cations resulted in substantial variation of the reactivity of the surface oxygen as well as bonding strength and coverages of surface ad-NOx species. It was reflected in substantial improvement of the low-temperature activity of these systems as compared with those containing separate components. The nature of cation used for pillar modification was found to affect catalytic properties of supported active components, which can be explained by variation of the pillars structure and uniformity of their spatial distribution in clay galleries.


35.
Oscillations in Partial Oxidation of Methane to Syngas over Supported Mixed Oxides Promoted with Pt

A. V. Simakov, S. N. Pavlova, N. N. Sazonova, V. A. Sadykov, O. I. Snegurenko, V. A. Rogov, V. N. Parmon, I. A. Zolotarskii, V. A. Kuzmin and E. M. Moroz
G. K. Boreskov Institute of Catalysis, Siberian Branch of the Russian Academy of Sciences,
Pr. Akademika Lavrentyeva 5, Novosibirsk 630090 (Russia), E-mail: pavlova@catalysis.nsk.su
Страницы: 263-270

Аннотация >>
Ni, Pt, lanthanum nickelate with and without Pt supported on corundum carrier either pure or promoted with CeO2–ZrO2 were tested in partial methane oxidation (POM) to synthesis gas under conditions (high temperature, short contact time, highly diluted gas mixture, small catalyst grains) providing studying of the intrinsic kinetics. The phase composition and reducibility of catalysts were characterized with XRD and TPR technique. The influence of catalyst composition on the catalyst performance has been studied. The self-sustained oscillations of methane conversion and products concentration have been observed. The nature of those oscillations is discussed taking into account the intrinsic properties of the catalysts clarified with TPR and XRD.


36.
The Catalytic Method of Verbanol Preparation with Controlled Isomer Distribution Starting from Renewable Material α-Pinene

I. L. Simakova and V. A. Semikolenov
G. K. Boreskov Institute of Catalysis, Siberian Branch of the Russian Academy of Sciences,
Pr. Akademika Lavrentyeva 5, Novosibirsk 630090 (Russia), E-mail: simakova@catalysis.nsk.su
Страницы: 271-276

Аннотация >>
The reasonable scheme of commercially valuable odour chemicals syntheses starting from renewable natural material α-pinene includes the explored reaction of verbenol hydrogenation into verbanol under mild conditions over Pd/C catalyst. The possibility of verbanol stereoisomers preparation with controlled isomer distribution that defines a practical use of scheme as a whole is considered. The effects of the hydrogen pressure, temperature and catalyst content on the isomers re-proportioning in the course of verbenol hydrogenation are studied. The main factors permitting the hydrogenation process to direct to the definite verbanol isomers production were found to be hydrogen pressure and reaction temperature. Isoverbanol/neoiso verbanol ratio increases with hydrogen pressure growth from 2 to 11 bar and temperature decrease from 50 to 90 °C.


37.
Combustion and Processing of Rice Husk in the Vibrofluidized Bed of Catalyst or Inert Material

A. D. Simonov, T. I. Mishenko, N. A. Yazykov and V. N. Parmon
G. K. Boreskov Institute of Catalysis, Siberian Branch of the Russian Academy of Sciences,
Pr. Akademika Lavrentyeva 5, Novosibirsk 630090 (Russia), E-mail: A. D. Simonov@catalysis.nsk.su
Страницы: 277-284

Аннотация >>
In the present work, some data on catalytic combustion of one of the most widespread vegetative remainders – rice husk are adduced. The rice husk is used not only as a fuel, but also as a source of silicon for semiconductor industry, the synthesis of silicon carbides and silicon nitrides, etc. We studied the rice husk oxidation in the vibrofluidized bed of either a catalyst or an inert material in conditions allowing to reproduce with an adequate accuracy the data on scraps combustion in the dense and unloaded phase of the fluidized bed. It is found that the process of the rice husk combustion is localized completely in the bed of the catalyst. In the bed of an inert material the process occurs in a space above the bed; consequently, exhausts contain a fair quantity of CO. Studies on solid products of the rice husk combustion have shown that their texture is determined mainly by silica, which is contained in rice husk as amorphous silica SiO2 × nH2O. The adsorption ability of these solid products in respect to methylene blue (MB) is investigated. With increasing the process temperature, the value of limiting MB adsorption by the solid products passes through a maximum at the process temperature 600 °C. It is found that the values of the limiting MB adsorption for the solid combustion products in the bed of the catalyst exceed those for solid products obtained in the bed of an inert material. Under discussion are also some distinctions of the process of rice husk processing in the vibrofluidized beds of either catalyst or inert material.


38.
Fischer–Tropsch Synthesis with the Use of a Porous Catalyst Packing. Feasibility Study of Performing Multiphase Catalytic Process Using Permeable Composite Monoliths

A. G. Sipatrov, A. A. Khassin, T. M. Yurieva, V. A. Kirillov, G. K. Chermashentseva and V. N. Parmon
G. K. Boreskov Institute of Catalysis, Siberian Branch of the Russian Academy of Sciences,
Pr. Akademika Lavrentyeva 5, Novosibirsk 630090 (Russia), E-mail: los@catalysis.nsk.su
Страницы: 293-296

Аннотация >>
A novel scheme for the organization of the three-phase process has been proposed, basing on a new type of a stochastically organized porous and catalytically active composite monolith (PCM). The high catalyst loading (1 g/cm3) and high heat conductivity (3 W/(m K)) make this new material very attractive for exothermic multiphase processes, e. g. for the Fischer–Tropsch synthesis. The possibility of preparing strong PCMs with the permeability of 10–500 mDarcy has been demonstrated. The gas-vapor phase flow through a PCM particle can be performed via transport pores which diameter was measured as 4–10 mm. The pressure drop has been shown to be reasonable for the Fischer–Tropsch synthesis. The effectiveness of the PCM usage at 0.1MPa, 210 °C has been found to be above 70 %. PCM material was concluded to be the prospective


39.
Radial Heat Transfer in Packed Beds of Shaped Particles

E. I. Smirnov1, A. V. Muzykantov1, V. A. Kuzmin1, I. A. Zolotarskii1, G. W. Koning2 and A. E. Kronberg 2
Страницы: 293-296

Аннотация >>
Experimental data on the effective radial thermal conductivities and wall heat transfer coefficients of cylindrical beds formed of 4-hole and 52-hole cylindrical pellets, 6-spoke wheels and 3-hole trilobed particles are presented. A model with a linear variation of the radial thermal conductivity in the vicinity of the wall is proposed for description of the radial heat transfer in the packed bed. The model allows simple correlation between the wall Nusselt number and the bed core effective radial thermal conductivity. The model does not require any additional empirical parameters for the description of heat transfer in packed beds of different shaped particles.


40.
Monometallic and Bimetallic Pt- and Ru-Based Catalysts for Selective Oxidation of CO in Excess Hydrogen

P. V. Snytnikov1, V. A. Sobyanin1, V. D. Belyaev1 and D. A. Shlyapin2
1G. K. Boreskov Institute of Catalysis, Siberian Branch of the Russian Academy of Sciences,
Pr. Akademika Lavrentyeva 5, Novosibirsk 630090 (Russia), E-mail: sobyanin@catalysis.nsk.su
2Omsk Branch of the United Institute of Catalysis, Siberian Branch of the Russian Academy of Sciences, Ul. Neftezavodskaya 54, Omsk 644040 (Russia)
Страницы: 297-302

Аннотация >>
Selective oxidation of CO in excess hydrogen and in the presence of CO2 and H2O has been studied over monometallic Pt, Ru and bimetallic Pt–Ru supported on porous carbonaceous material catalysts. The catalysts provided CO conversion ³98 % and seem to be promising for efficient single-step removal of CO from hydrogen-rich streams containing CO2 and H2O.


41.
Microspheres of Fly Ash as a Source for Catalytic Supports, Adsorbents and Catalysts

S. N. Vereshchagin1, N. N. Anshits1, A. N. Salanov2, O. M. Sharonova1, T. A. Vereshchagina1 and A. G. Anshits1
1Institute of Chemistry and Chemical Technology,
Siberian Branch of the Russian Academy of Sciences,
Ul. K. Marxa 42, Krasnoyarsk 660049 (Russia), E-mail: snv@icct.ru
2G. K. Boreskov Institute of Catalysis, Siberian Branch of the Russian Academy of Sciences,
Pr. Akademika Lavrentyeva 5, Novosibirsk 630090 (Russia)
Страницы: 303-308

Аннотация >>
The present paper reviews the processes of separation of microspheres from fly ash and their possible applications for the creation of catalytic supports, adsorbents and catalysts. To isolate magnetic microspheres and cenospheres of stabilized composition, the process flowsheets of concentrate separation, based on the combination of hydro- or aerodynamic and granulometric classification, followed by the separation in magnetic field of different intensity, were developed. Novel materials based on cenospheres of stabilized composition, such as mesoporous microspherical glasses (specific surface area Ssp = 3–50 m2/g), the supported iron oxide systems (Ssp = 50–200 m2/g), and zeolites are described. Spherical zeolites demonstrated good ion exchange properties of in cesium and strontium removal from the technological solutions. The catalytic properties of Fe2O3/cenosphere catalysts and magnetic microspheres in deep oxidation of methane are discussed.


42.
The Cu-ZSM-5 Catalysts Washcoated on Monolith for Diesel Vehicle Emission Control

S. A. Yashnik1, L. T. Tsykoza1, Z. R. Ismagilov1, V. A. Sazonov1, N. V. Shikina1, V. V. Kuznetsov1, I. A. Ovsyannikova1, N. M. Danchenko2, S. P. Denisov2 and H. J. Veringa 3
1 G. K. Boreskov Institute of Catalysis, Siberian Branch of the Russian Academy of Sciences,
Pr. Akademika Lavrentyeva 5, Novosibirsk 630090 (Russia), E-mail: ZRI@catalysis.nsk.su
2Ural Electrochemical Plant, Novoural&#39sk (Russia)
3ECN, Westerduiinweg 3, 1755 ZG Petten (The Netherlands)
Страницы: 309-320

Аннотация >>
The composition of modified monolith zeolite catalysts containing the basic components in the washcoating layer is suggested. When the washcoating layer contains 80 % zeolite, 10 % TiO2, and 10 % Al2O3, the catalyst exhibits both activity and adhesion strength. The titanium catalyst is stable to sulfur poisoning (H2S) at 500 °C; a small decrease in the catalyst activity at 400 °C is no longer observed after regeneration. Introducing 4 % mass Ce (calculated for respect to the washcoating) into the ready catalyst, one can preserve the catalyst activity and provide its stabile operation in the presence of water vapour both at 400 and 500 °C. Activity of the titanium-cerium-modified monolith catalyst is stable in the presence of water vapour and sulphur compounds in the gas mixture at a time.


43.
Fuel Combustion in the Fluidized Bed of an Inert Material Equipped with an Unmovable Catalytic Small-Volume Package

N. A. Yazykov, A. D. Simonov, T. I. Mishenko, A. S. Aflyatunov, S. V. Smolin and V. N. Parmon
G. K. Boreskov Institute of Catalysis, Siberian Branch of the Russian Academy of Sciences,
Pr. Akademika Lavrentyeva 5, Novosibirsk 630090 (Russia), E-mail: A.D. Simonov@catalysis.nsk.su
Страницы: 321-326

Аннотация >>
The capability of combustion of solid fuels (such as the brown coal of the Kansk-Achinsk coal deposit) in the fluidized bed of an inert material in the presence of unmovable catalytic packages is investigated. This arrangement of the catalytic process is shown to allow the achievement of the same parameters of the fuel burn off and the content of toxic substances in the flue gas as in the case of fuel combustion in the fluidized bed of catalyst grains. The new arrangement of catalytic processes can be recommended for the accomplishing of some other exothermic catalytic reactions which require the maintenance of isothermal conditions.