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Abstracts

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Catalysis in Organic Synthesis

NEW METHOD OF DIMETHYL SULFIDE SYNTHESIS

A.V. Mashkina

Russ. J. Org. Chem., 47(5) (2011) pp. 678-681.

The synthesis of dimethyl sulfide consists in the reaction of dimethyl disulfide with methanol in the presence of solid catalyst, aluminum γ-oxide. The yield of dimethyl sulfide grows with growing temperature, contact time, and content of methanol in the reaction mixture. At 350-400°C, molar ratio methanol-dimethyldisulfide 2.0-2.5, and total conversion of the reagents the yield of dimethyl sulfide reached 95 mol%.

A CATALYTIC PROCESS FOR PREPARATION OF THIOPHENE FROM FURAN AND HYDROGEN SULFIDE

A.V. Mashkina

Russ. J. Appl. Chem., 84(7) (2011) pp. 1223-1228.

Thiophene formation under various conditions from furan and Н2S in the presence of γ-Al2O3, both unpromoted and promoted with transition metal oxides, was examined. The conditions enabling preparation of thiophene in a 95–98 mol% yield were determined.

INVESTIGATION OF THE MECHANISM OF CATALYTIC RECYCLIZATION OF FURAN TO THIOPHENE

A.V. Mashkina

Chem. Heterocycl. Compd., 9 (2010) pp. 1063-1067.

Investigation of the formation of thiophene from furan and hydrogen sulfide at various catalysts showed that the activity of the catalysts increases with increase in the strength and concentration of Lewis acid centers. It was found by IR spectroscopy that if the degree of coverage of the aluminum oxide surface with hydrogen sulfide is higher than monolayer its dissociative chemisorption does not occur. Mechanism was postulated which assume that the reaction takes place through stage with the formation of a surface intermediate, including coordination of the α-carbon atoms of the furan ring with the Lewis acid center and with the sulfur atom of molecular hydrogen sulfide.

EPOXIDATION OF BUTADIENE WITH HYDROGEN PEROXIDE CATALYZED BY THE SALTS OF PHOSPHOTUNGSTATE ANIONS: RELATION BETWEEN CATALYTIC ACTIVITY AND COMPOSITION OF INTERMEDIATE PEROXO COMPLEXES

L.I. Kuznetsova, N.I. Kuznetsova, R.I. Maksimovskaya, G.I. Aleshina, O.S. Koscheeva*, V.A. Utkin (*Nikolaev Institute of Inorganic Chemistry, Novosibirsk, Russia)

Catal. Lett., 141(10) (2011) pp. 1442-1450.

Epoxidation of 1,3-butadiene has been studied in acetonitrile solutions of aqueous H2O2 and tetrabutylammonium or 1-ethyl-3-methylimidazolium salts of phosphotungstate anions:

[(n-C4H9)4N]3{PO4[WO(O2)2]4}, [(n-C4H9)4N]5Na0.6H1.4[PW11O39] or [(C2H5)(CH3)C3H3N2]5NaH[PW11O39]. The selectivity of the 1,3-butadiene to 3,4-epoxy-1-butene (EpB) conversion attains 97% at nearly 100% efficiency of the H2O2 consumption. The rate of the EpB formation has been correlated with the solution compositions as found by 31P NMR under the reaction conditions.

Bis[3-(3,5-DIALKYL-4-HYDROXYPHENYL)PROPYL]MONO- AND DISULFIDES AS THE SEVILEN STABILIZERS

A.P. Krysin*, T.B. Khlebnikova (*Vorozhtsov Novosibirsk Institute of Organic Chemistry, Novosibirsk, Russia)

Russ. J. Gen. Chem., 81(6) (2011) pp. 1159-1162.

The effect of the shielding degree of the phenol hydroxy group on the hydrolytic and thermal stability of ethylene-vinyl acetate copolymer (Sevilen) was studied on a series of phenols containing one or two sulfur atoms in the aliphatic chain of the para-substituent. Among the synthesized compounds a group of disulfides was found with a high antioxidant efficiency, which increase the Sevilen hydrolytic stability. The most effective are the 6-tert-butyl-2-methylphenol derivatives.

NEW APPROACH TO THE SYNTHESIS OF tris(PERFLUOROALKYL)BORANE ADDUCTS WITH DIALKYLAMINES

N.Yu. Adonin, V.V. Bardin*, U. Florke**, H.-J. Fron*** (*Vorozhtsov Novosibirsk Institute of Organic Chemistry, Novosibirsk, Russia; **Paderborn University, Germany; ***Duisburg-Essen University, Germany)

Russ. J. Gen. Chem., 81(3) (2011) pp. 509-516.

A convenient synthetic approach to the adducts (CnF2n+1)3BNHR2 (n = 2–4, 6; R = Me, Et) was developed, based on the reaction of lithium perfluoroalkyls with dichloro(dialkylamino)boranes at temperatures below –90°C. The target products can be synthesized with preparative yields of 50–90%.

MECHANISTIC INSIGHTS INTO OXIDATION OF 2-METHYL-1-NAPHTHOL WITH DIOXYGEN: AUTOXIDATION OR A SPIN-FORBIDDEN REACTION?

O.A. Kholdeeva, I.D. Ivanchikova, O.V. Zalomaeva, A.B. Sorokin*, I.Y. Skobelev, E.P. Talsi (*Institut de Recherches sur la Catalyse, Villeurbanne Cedex, France)

J. Phys. Chem. B, 115(42) (2011) pp. 11971–11983.

Oxidation of 2-methyl-1-naphthol (MNL) with molecular oxygen proceeds efficiently under mild reaction conditions (3 atm O2, 60–80°C) in the absence of any catalyst or sensitizer and produces 2-methyl-1,4-naphthoquinone (MNQ, menadione, or vitamin K3) with selectivity up to 80% in nonpolar solvents. 1H NMR and 1H,1H-COSY studies revealed the formation of 2-methyl-4-hydroperoxynaphthalene-1(4H)-one (HP) during the reaction course. Several mechanistic hypotheses, including conventional radical autoxidation, electron transfer mechanisms, photooxygenation, and thermal intersystem crossing (ISC), have been evaluated using spectroscopic, mass-spectrometric, spin-trapping, 18O2 labeling, kinetic, and computational techniques. Several facts collectively implicate that ISC contributes significantly into MNL oxidation with O2 at elevated pressure: (i) the reaction rate is unaffected by light; (ii) C–C-coupling dimers are practically absent; (iii) the reaction is first order in both MNL and O2; (iv) the observed activation parameters (ΔH = 8.1 kcal mol–1 and ΔS = -50 eu) are similar to those found for the spin-forbidden oxidation of helianthrene with 3O2 (Seip, M.; Brauer, H.-D.J. Am. Chem. Soc.1992, 114, 4486); and (v) the external heavy atom effect (2-fold increase of the reaction rate in iodobenzene) points to spin inversion in the rate-limiting step.

SYNTHESIS OF A NEW OPTICALLY PURE CHIRAL DIAMINE FROM LEVOPIMARIC ACID

V.N. Konev, T.B. Khlebnikova, Z.P. Pai

Chem. Sustain. Devel., 19(2) (2011) pp. 165-168.

Synthesis of a new chiral optically pure diamine of diterpene series was carried out on the basis of the components of available natural renewable raw material. The resulting tricyclic trans-1,2-diamine and its derivatives can be used as the ligands in metal complex catalysts of asymmetrical reactions.

MEERWEIN–PONNDORF–VERLEY REDUCTION OF ALDEHYDES FORMED in situ FROM α- AND β-PINENE EPOXIDES IN A SUPERCRITICAL FLUID IN THE PRESENCE OF ALUMINA

V. Il`ina*, S.Yu. Kurbakova*, K.P. Volcho*, N.F. Salakhutdinov*, V.I. Anikeev (*Vorozhtsov Novosibirsk Institute of Organic Chemistry, Novosibirsk, Russia)

J. Saudi Chem. Soc., 15(4) (2011) pp. 313-317.

The use of a system consisting of flow-type reactor, supercritical fluid containing isopropanol/CO2 and alumina as a catalyst allows the one-pot isomerization of α- and β-pinene epoxides into campholenic aldehyde and myrtanal and Meerwein– Ponndorf–Verley reduction of these aldehydes to the corresponding alcohols.

REARRANGEMENTS OF VERBENOL EPOXIDE IN SUPERCRITICAL FLUIDS

K.P. Volcho*, I.V. Il`ina*, N.F. Salakhutdinov*, V.I. Anikeev (*Vorozhtsov Novosibirsk Institute of Organic Chemistry, Novosibirsk, Russia)

ARKIVOC, 8 (2011) pp. 134-140.

Transformations of verbenol epoxide in a supercritical mixture of CO2, isopropyl alcohol, and water were studied. The main identified products were similar to those obtained in the presence of Montmorillonite clays, but with much shorter contact times and without an acid catalyst. The reactivity of verbenol epoxide in supercritical media differs dramatically from the behavior of this epoxide in the presence of Lewis acid ZnBr2. In contrast to studies of α-pinene epoxide transformations, the presence of water caused no essential changes in product distribution. The presence of triethylamine suppressed the rearrangements; obviously the reaction has cationic character.

STEP CHANGES AND DEACTIVATION BEHAVIOR IN THE CONTINUOUS DECARBOXYLATION OF STEARIC ACID

A.Th. Madsen*,**, B. Rozmyszowicz**, I.L. Simakova, T. Kilpiö**, A.-R. Leino***, K. Kordás***, K. Eränen**, P. Mäki-Arvela**, D.Yu. Murzin** (*Technical University of Denmark, Lyngby, Denmark; **Abo Akademi University, Turku, Finland; ***University of Oulu, Oulu, Finland)

Ind. Eng. Chem. Res., 50(19) (2011) pp. 11049–11058.

Deoxygenation of dilute and concentrated stearic acid over 2% Pd/C beads was performed in a continuous reactor at 300°C and 20 bar pressure of Ar or 5% H2/Ar. Stable operation was obtained in 5% H2 atmosphere, with 95% conversion of 10 mol % dilute stearic acid in dodecane and 12% conversion of pure stearic acid. Deactivation took place in H2-deficient gas atmosphere, probably as a result of the formation of unsaturated products and coking in the pore system. Transient experiments with step changes were performed: 1 h was required for the step change to be visible in liquid sampling, whereas steady states were achieved after a total of 2.5–3 h. Postreaction analysis of the spent catalyst revealed that a deactivation profile was formed downward over the catalyst bed.

THE CHEMISTRY OF 2,3-DIHYDROISOXAZOLE DERIVATIVES

N.V. Chukanov, V.A. Reznikov* (*Vorozhtsov Institute of Organic Chemistry, Novosibirsk, Russia)

Russ. Chem. Bull., 60(3) (2011) pp. 379-399.

Methods for the synthesis and transformations of 2,3-dihydroisoxazole derivatives are reviewed. Data on reduction and oxidation reactions and intramolecular rearrangements are generalized; their mechanisms are discussed.

Mathematical Simulation, Calculating Models

EVALUATION OF GOLD ON ALUMINA CATALYST DEACTIVATION DYNAMICS DURING α-PINENE ISOMERIZATION

Yu.S. Solkina, S.I. Reshetnikov, M. Estrada*, A.V. Simakov**, D.Yu. Murzin***, I.L. Simakova

(*Posgrado de Fisica de Materiales de CICESE-UNAM, Ensenada, B.C., Mexico; **Universidad Nacional Autonoma de Mexico, Ensenada, B.C., Mexico; ***Abo Akademi University, PCC, Turku/Abo, Finland)

Chem. Eng. J., 176-177 (2011) pp. 42-48.

Synthesis of camphene is an important step in an industrial process for camphor production from α-pinene. Compared to conventional way of α-pinene to camphene transformation over acid-hydrated TiO2, gold on alumina catalyst was found to provide α-pinene isomerization conversion up to 99.9% and selectivity 60–80% making this catalyst very promising from an industrial viewpoint. However, deactivation of gold catalyst might be a serious obstacle for real industrial implementation. According to TPO and UV–vis-mass in situ it was shown that deactivation is caused by adsorption of hydrocarbons on the gold species. The dynamics of catalyst deactivation during α-pinene isomerization was presented based on a so-called “separable” deactivation model assumption. Effects of isomerization temperature, initial α-pinene concentration and gas atmosphere on catalyst deactivation with time-on-stream were investigated experimentally and correlated with the proposed deactivation function. The results showed that the α-pinene concentration was the major factor governing the deactivation of Au/γ-Al2O3 catalyst under substrate-feeding conditions. When the α-pinene concentration was controlled at a relatively low level such as 0.4 vol.%, especially in hydrogen atmosphere, the total deactivation rate was negligible. An equation of the reaction rate taking into account the catalyst deactivation was suggested making prediction of deactivation behavior in α-pinene conversion at different initial concentrations.

INFLUENCE OF CLUSTER SIZE DISTRIBUTION ON CLUSTER SIZE DEPENDENT CATALYTIC KINETICS

D.Yu. Murzin*, I.L. Simakova (*Åbo Akademi University, Turku, Finland)

Catal. Lett., 141(7) (2011) pp. 982-986.

A theoretical analysis of the influence of particle size distribution on observed TOF dependence on cluster size is presented for a two step catalytic cycle. Such mechanism can display different TOF behavior including maxima. In the later case simulations demonstrated broadening of TOF curves compared to an idealized case of very narrow PSD. However, for more often observed cases with smooth TOF increase or decrease with cluster size increase incorporation of particle size distribution in kinetic analysis is not required at least for often experimentally observed particle size distributions.

THERMODYNAMIC ANALYSIS OF THE CLUSTER SIZE EVOLUTION IN CATALYST PREPARATION BY DEPOSITION–PRECIPITATION

D.Yu. Murzin*, O.A. Simakova, I.L. Simakova, V.N. Parmon (*Åbo Akademi University, Turku, Finland)

React. Kinet. Mech. Catal., 104(2) (2011) pp. 259-266.

Several gold catalysts supported on various inorganic supports with different point zero charge (pzc) were prepared by deposition–precipitation with urea (DPU). A thermodynamic model accounting for cluster evolution was advanced. The key element in the model is the dependence of the interfacial energy on the relative approach to pzc during DP. Experimental data were compared with the model, showing a possibility to utilize the theoretical approach to predict the cluster size.

MODELING AND CALCULATION OF THE PROCESS OF RAPID EXPANSION OF SUPERCRITICAL FLUID YIELDING NANOPARTICLES

V.I. Anikeev, D.A. Stepanov, An. Yermakova

Theor. Found. Chem. Eng., 45(2) (2011) pp. 141-155.

A mathematical model is proposed and the calculation is carried out for the process of rapid expansion of the supercritical fluid containing a dissolved solid compound via a capillary into a volume with specified temperature and pressure. The analysis of sensitivity of the model toward the process parameters makes it possible to choose the most important parameters for producing nanoparticles with preset properties and dimensions. The calculations demonstrate that all the parameters of the expansion process under study have a particular effect on the size of the particles being formed.

PHASE AND CHEMICAL EQUILIBRIA IN THE TRANSESTERIFICATION REACTION OF VEGETABLE OILS WITH SUPERCRITICAL LOWER ALCOHOLS

V.I. Anikeev, D.A. Stepanov, An. Yermakova

Russ. J. Phys. Chem. A, 85(8) (2011) pp. 1336-1346.

Calculations of thermodynamic data are performed for fatty acid triglycerides, free fatty acids, and fatty acid methyl esters, participants of the transesterification reaction of vegetable oils that occurs in methanol. Using the obtained thermodynamic parameters, the phase diagrams for the reaction mixture are constructed, and the chemical equilibria of the esterification reaction of free fatty acids and the transesterification reaction of fatty acid triglycerides attained upon treatment with supercritical methanol are determined. Relying on the analysis of the obtained equilibria for the esterification reaction of fatty acids and the transesterification reaction of triglycerides attained upon treatment with lower alcohols, the authors select the optimum conditions for performing the reaction in practice.

CALCULATING THE THERMODYNAMIC CHARACTERISTICS OF THE STEPWISE TRANSESTERIFICATION OF SIMPLE TRIGLYCERIDES

V.I. Anikeev, D.A. Stepanov, An. Yermakova

Russ. J. Phys. Chem. A, 85(12) (2011) pp. 2082-2087.

Thermodynamic data for mono- and diglycerides of palmitic, oleic, and linoleic fatty acids participating in the stepwise transesterification reaction of the corresponding simple triglycerides in methanol are calculated. The obtained thermodynamic parameters allow to calculate the chemical equilibrium and the equilibrium composition of the products of the stepwise transesterification reaction of fatty acid triglycerides with supercritical methanol.

CALCULATIONS OF PHASE EQUILIBRIA FOR MIXTURES OF TRIGLYCERIDES, FATTY ACIDS, AND THEIR ESTERS IN LOWER ALCOHOLS

D.A. Stepanov, An. Yermakova, V.I. Anikeev

Russ. J. Phys. Chem. A, 85(1) (2011) pp. 21-25.

The objects of study were mixtures containing triglycerides and lower alcohols and also the products of the transesterification of triglycerides, glycerol and fatty acid esters. The Redlich-Kwong-Soave equation of state was used as a thermodynamic model for the phase state of the selected mixtures over wide temperature, pressure, and composition ranges. Group methods were applied to determine the critical parameters of pure substances and their acentric factors. The parameters obtained were used to calculate the phase diagrams and critical parameters of mixtures containing triglycerides and lower alcohols and the products of the transesterification of triglycerides, glycerol and fatty acid esters, at various alcohol/oil ratios. The conditions of triglyceride transesterification in various lower alcohols providing the supercritical state of reaction mixtures were selected.

 

REACTION REVERSIBILITY IN α-PINENE THERMAL ISOMERIZATION: IMPROVING THE KINETIC MODEL

A.M. Chibiryaev*, An. Yermakova, I.V. Kozhevnikov (Worozhtsov Institute of Organic Chemistry, Novosibirsk, Russia)

Russ. J. Phys. Chem. A, 85(8) (2011) pp. 1347-1357.

Revision of the experimental data on a-pinene thermal isomerization attained in supercritical ethanol allowed to expand the reaction scheme, which includes now six main products and eleven reversible reactions. The equilibrium constants of every reaction (KT,- and КФ, ) were calculated to allow for reversibility of reactions. The thermochemical data of the pure compounds required to calculate constants KTj- and K<S>j (standard enthalpy and entropy of formation AfH (298.15 K), AfS (298.15 K), heat capacity CP(T), critical parameters Tcr and pcr, boiling point Тb, and the acentric factor со) were preliminary estimated using the empirical Joback and Benson methods. A kinetic model based on the new expanded scheme of reversible reactions was successfully identified and its kinetic parameters kj (600 K) and Ej were determined. Detailed examination of the new kinetic model allowed us to refine the generally accepted mechanism of a-pinene thermal isomerization and to distinguish additional features of the multistep process.

ACTIVATION PARAMETERS OF SUPERCRITICAL AND GAS-PHASE β-PINENE THERMAL ISOMERIZATION

A.M. Chibiryaev*, An. Yermakova,I.V. Kozhevnikov (*Worozhtsov Institute of Organic Chemistry, Novosibirsk, Russia)

Russ. J. Phys. Chem. A, 85(9) (2011) pp. 1505-1515.

New data on enthalpy and entropy contributions to the energy barrier of p-pinene thermal isomerization were obtained. The rate of P-pinene conversion is higher in supercritical EtOH (P = 120 atm) than in the gas phase (P < 1 atm, without solvent, or for inert carrier gas N2) at equal temperatures. The highest activation energy Еъ of total P-pinene conversion is also observed in reactions in the supercritical (sc) condition. Activation parameters AH-/, AS/, and AG-/ depend strongly on the reaction pressure. Thus, at P < 1 atm (gas-phase reaction) the values of AS"/ are negative, while at sc conditions at P = 120 atm is positive. The linear dependences lnfe0 ~ Ey. and AS"/ - AS"/ indicate an isokinetic relation (IKR) and enthalpy-entropy compensation effect (EEC). The isokinetic temperature was calculated (Tiso = 605.5 ± 22.7 K). It was shown that elevation of temperature reduces the value of AG/(7) upon sc thermolysis only, whereas in all gas-phase reactions AG/(7) increases. At equal reaction temperatures, the greatest values of Keq#(T) proved to be typical for thermolysis in sc-EtOH. It was hypothesized that the rate of total p-pinene conversion increases dramatically due to a considerable shift in equilibrium toward higher concentrations of activated complex >-TS#. A detailed analysis of activation parameters shows that the IKR and EEC coincide, evidence of a common mechanism of p-pinene conversion observed under different reaction conditions, including thermolysis in sc-EtOH.

MATHEMATICAL MODELING OF β-PICOLINE OXIDATION TO NICOTINIC ACID IN MULTITUBULAR REACTOR: EFFECT OF THE GAS RECYCLE

E.V. Ovchinnikova, N.V. Vernikovskaya, T.V. Andrushkevich, V.A. Chumachenko

Chem. Eng. J., 176-177 (2011) pp. 114-123.

Mathematical modeling of nicotinic acid synthesis process by means of p-picoline air oxidation in multitubular reactor was carried out. Factors that impact the process efficiency were studied. Special attention was focused on the role of recycling. The analysis was based on a two-dimensional quasi-homogeneous mathematical model of a tubular reactor and proprietary kinetic model of p-picoline oxidation over V2O5-TiO2 catalyst.

MATHEMATICAL MODELING OF THE PROPANE DEHYDROGENATION PROCESS IN THE CATALYTIC MEMBRANE REACTOR

E.V. Shelepova, A.A. Vedyagin, I.V. Mishakov, A.S. Noskov

Chem. Eng. J., 176-177 (2011) pp. 151-157.

The two-dimensional non-isothermal stationary mathematical model of the catalytic membrane reactor for the process of propane dehydrogenation has been developed. The made calculations have shown the higher efficiency of the membrane reactor in comparison with the tubular one which is achieved due to removal of hydrogen from reactionary zone through the membrane to shift the reaction equilibrium towards formation of products. The use of membrane was found to cause the propane conversion increase from 41% to 67%. The highest value of propane conversion (X = 96%) was reached in case of additional oxidation of the removed hydrogen (conjugated dehydrogenation). The maximum value of propylene selectivity S = 98% can be as well reached in case of conjugated dehydrogenation in the membrane reactor at the reaction temperature of 500°C. The oxidation of hydrogen in conjugated dehydrogenation process gives the increase of propylene yield from 65% (the tubular reactor) to 95%. The maximum propylene yield corresponds to T = 525°C. It was also established that the gas space velocity in both internal and external parts of the membrane reactor is to be the one of the most important factors defining efficiency of the conjugated dehydrogenation process.

EFFECT OF CATALYTIC COMBUSTION OF HYDROGEN ON THE DEHYDROGENATION PROCESSES IN A MEMBRANE REACTOR. I. MATHEMATICAL MODEL OF THE PROCESS

E.V. Shelepova, A.A. Vedyagin, A.S. Noskov

Combust. Explos. Shock Waves, 47(5) (2011) pp. 499-507.

Mathematical modeling of a catalytic membrane reactor was performed for thermodynamically coupled processes using as an example the endothermic dehydrogenation of propane and the exothermic combustion (oxidation) of hydrogen. Benefits of using the membrane reactor to increase the yield of target products by shifting equilibrium was demonstrated theoretically. The effect of hydrogen combustion on the main characteristics of the endothermic dehydrogenation process was studied. The hydrogen combustion reaction makes it possible to further increase the conversion of propane and compensate for the energy consumption in the endothermic dehydrogenation process.

VARIATIONAL PRINCIPLES IN IRREVERSIBLE THERMODYNAMICS WITH APPLICATION TO COMBUSTION WAVES

A.P. Gerasev

J. Non-Equilib. Thermodyn., 36(1) (2011) pp. 55-73.

The thermodynamics of physicochemical processes in a reacting distributed kinetic system are considered, and the entropy balance equation for traveling waves of laminar combustion is derived for arbitrary Lewis number. Qualitative and numerical analysis of a dynamic system with a three-dimensional phase space and of the local and complete entropy production in the system were performed. It is shown that the complete entropy production in the system is a functional of the traveling wave solution of the problem, possessing extreme properties, whose minimum corresponds to the only physically meaningful traveling wave solution. The procedure of “cut-off” (zeroing) of the reaction rate is justified by methods of non-equilibrium thermodynamics. A variational formulation of the problem is presented for calculation of a steady laminar combustion wave.

SIMULATION OF CATALYTIC PROCESSES IN A FIXED BED WITH THE USE OF MICROWAVE RADIATION FOR PERFORMING AN ENDOTHERMIC REACTION

A.P. Gerasev

Kinet. Catal., 52(6) (2011) pp. 907-913.

A quasi-homogeneous model of a catalytic fixed-bed reactor, in which an endothermic chemical reaction occurs with the use of microwave radiation energy, was proposed and numerically analyzed. The versions of the arrangement of a radiation source at the reactor inlet and outlet and also the versions of microwave radiation energy conversion into heat by a catalyst and an initial gaseous reagent were considered. The effects of model parameters on the dynamic behavior of the system were studied, and a qualitative structural difference between the resulting steady-state conditions was demonstrated. The phenomenon of endothermic chemical reaction autowave propagation was discovered, and the regularities of this propagation were studied.

DISTRIBUTION OF CATALYTIC, FILTRATIONAL AND HYBRID AUTOWAVES IN THE HETEROGENEOUS ENVIRONMENT

A.P. Gerasev

Chem. Ind. Today, 1 (2011) pp. 6-12.

Mathematical modeling of autowave heterogeneous processes with chemical reactions in a gas phase and on the catalyst is carried out. Values of factors of interphase heat– and masstransfer and heat conductivity of a solid phase were defined on current values of parameters of system. Qualitative distinction of structure of three kinds of autowaves is shown: filtrational burning of gases in a mode of low speeds, with catalytic reaction and hybrid autowaves with simultaneously going reactions in a gas phase and on the catalyst. Numerical modelling of the system on the basic technological indicators of autowave process is performed.

KINETICS STUDY OF THE PERCHLOROETHYLENE HYDROFLUORINATION INTO PENTAFLUOROETHANE (FREON 125) OVER CHROMIUM-BASED CATALYST

S.I. Reshetnikov, A.A. Zirka, R.V. Petrov, E.A. Ivanov

Chem. Eng. J., 176-177 (2011) pp. 22-25.

The gas-phase hydrofluorination of perchloroethylene (PCE) into pentafluoroethane (non ozonedepleting Freon 125) at T = 330–390°C and P = 0.4 MPa in the presence of a chromium– magnesium catalyst has been studied. A hydrofluorination scheme including main product and by-products formation routes is deduced from the observed dependences of particular products selectivity. The kinetic model of the PCE hydrofluorination has been developed. The rate parameters and the activation energy of the reactions were determined. The model satisfactorily describes the experimental data in the temperature range 330–390°C.

EFFECT OF THE MOBILITY OF OXYGEN IN PEROVSKITE CATALYST ON THE DYNAMICS OF OXIDATIVE COUPLING OF METHANE

S.I. Reshetnikov, Yu.I. Pyatnitskii*,

L.Yu. Dolgikh* (*L.V. Pisarzhevskii Institute of Physical Chemistry, Kyiv, Ukraine)

Theor. Exp. Chem., 47(1) (2011) pp. 49-54.

The effect of the diffusion of oxygen from the volume of the catalyst to its surface on the dynamics of the oxidative coupling of methane was assessed on the basis of a mathematical model of the reaction of methane with the oxidized surface of KNaSrCoO3-x perovskite. It was shown that the possible values of the diffusion coefficient lie in the range of 10-18-10-16 cm2/s characteristic of the diffusion of oxygen in oxide catalysts.

THE STABILITY OF AN ISOTHERMAL GASEOUS SPHERE WITH GRAVITATION

V.N. Snytnikov, O.A. Stadnichenko

Astron. Rep., 55(3) (2011) pp. 214-223.

A dispersion relation has been obtained for waves propagating in an inhomogeneous gas with viscosity and gravity in the direction of the density gradient. It has been shown that a stationary distribution of isothermal gas is unstable under gravitational-convective perturbations. It is suggested that the initial- and boundary-value problems of the non-stationary dynamics of an isothermal gas with gravity but without viscosity are incorrect and require regularization, for example, by adding viscosity. The presence of viscosity does not prevent the development of the Jeans long-wave instability. Numerical experiments based on a fully three-dimensional, non-stationary numerical code have demonstrated the development of a collapse inside an isothermal cloud.

EFFECT OF WATER ON OXIDATIVE SCISSION OF 1-BUTENE TO ACETIC ACID OVER V2O5-TiO2 CATALYST. TRANSIENT ISOTOPIC AND KINETIC STUDY

W. Suprun*, E.M. Sadovskaya, Ch. Rüdinger**, H.-J. Eberle**, M. Lutecki*, H. Papp*

(*Universität Leipzig, Leipzig, Germany; **Wacker Chemie AG, Consortium für Elektrochemische Industrie GmbH, München, Germany)

Appl. Catal. A, 391(1-2) (2011) pp. 125-136.

The role of water in the oxidation of 1-butene to AcOH over VOx-TiO2 was investigated using spectroscopic and transient isotopic exchange methods. It was shown that the influence of water strongly depended on the temperature of reaction. In particular, DRIFTS and NH3-TPD studies confirmed the temperature influence on the acidity and the amount of adsorbed water. XPS investigations suggested that not only oxygen from vanadia, but also from the lattice of titania was involved in the oxygen transfer during the reaction. Formation of oxidation products proceeded over two types of active vanadium oxide centers, i.e., VOH and VO. Hydrated vanadium species exhibited high selectivity towards AcOH formation. On the other hand, VO centers favored total oxidation. Kinetic model was developed for an unambiguous interpretation of the experimental results. Modelled reaction constants of the formation of AcOH over VOH centers were ca. 3.5 times higher than over VO centers. At the same time, the reaction rate constant of total oxidation in the presence of water was ca. 3.2 times lower than in dry flow. Estimated values suggested that in the presence of water the number of VOH centers was substantially lower than VO sites; however their contribution to the rate of AcOH formation was much higher.

INVESTIGATION OF MASS TRANSFER ON GLASS FABRIC CATALYST DURING CO OXIDATION REACTION

О.V. Chub, А.S. Noskov, L.G. Simonova

Chem. Ind. Today, 5 (2011) pp. 19-24.

The mass transfer during CO oxidation reaction has been investigated using Pd-containing catalyst prepared on the basis of glass fabrics of various weaves. The mathematical model of experimental reactor is formulated. The results are shown in the form of criterial dependency Sh = A Ren Sc1/3, mass transfer coefficients and equation parameters have been determined.

ON А LIMIT EQUATIONS AND ATTRACTION FOR NONAUTONOMOUS SYSTEMS WITH DELAY

I.A. Finogenko*, N.A. Chumakova (*Institute for System Dynamics and Control Theory, Irkutsk, Russia)

Tambov University Reports. Ser.: Nat. Techn. Sci., 16(5) (2011) pp. 1247-1253.

For nonautonomous functional-differential equations property of quasiinvariance for limiting sets and analogue of the La-Salle principle of invariancy by use of Lyapunov functional with constant sign derivative is established.

COMPUTATIONAL FLUID DYNAMICS IN THE DESIGN OF CATALYTIC REACTORS

O.P. Klenov, A.S. Noskov

Catal. Ind., 3(4) (2011) pp. 331-349.

Computational fluid dynamics is becoming an important tool in the study of chemical engineering processes and apparatuses (in particular, the share of works with the application of this method is nearly 6% of the total number of all chemical engineering works issued by Elsevier Science Publishers in 2010). The possibilities of computational fluid dynamics are demonstrated using examples from three different chemical engineering fields: developing a method for loading a tubular reactor for the steam conversion of natural gas, studying heat transfer in a reactor for the hydrogenation of vegetable oils upon the replacement of a catalyst, and investigating the transitional processes in an automobile neutralizer. The results from computational fluid dynamics are verified by comparing them with experimental data in developing a method for loading a tubular reactor, using the problem of decelerating a catalyst particle with a flow of air as an example. The obtained data are compared with classical measurement data on the aerodynamic drag of a ball and a cylinder and represent the further development of works on the flow around particles of complex shape. In this work, the results from inspecting a reactor for the hydrogenation of oils with allowance for the possible heating and uniform distribution of a flow before its entering the catalyst bed are presented. It is shown that the construction of the reactor does not ensure homogeneity of the reaction flow at the desired level and requires modification of heating elements. The efficiency of computational fluid dynamics for investigating fast processes with a chemical reaction is exemplified by studying the transitional processes in an catalytic automobile neutralizer (the effect of flow dynamics and heat transfer on the thermal regime in a honeycomb catalyst particle is very difficult to study by experimental methods). The application of computational fluid dynamics allows us to reduce considerably the time and cost of developing and optimizing the designs of efficient catalytic fixed-, fluidized-, or moving-bed reactors (particularly multiphase stirred (slurry) reactors), along with mixers, adsorbers, bubblers, and other chemical engineering apparatuses with moving media.

SOLID DISPERSION IN THE SLURRY REACTOR WITH MULTIPLE IMPELLERS

O.P. Klenov, A.S. Noskov

Chem. Eng. J., 176-177 (2011) pp. 75-82.

A whole series of significant catalytic processes are carried out in a slurry reactor with multiple impellers. The selective hydrogenation of sunflower seed oil is the characteristic example of such a process. The liquid phase is the main medium into stirred tank and an investigation of a fluid dynamics of one just as transient regime of solid distribution in liquid volume could be helpful to practical application.

In the present work, CFD simulations have been carried out to study solid distribution in liquid–solid stirred tank using Mixture multifluid approach along with standard k-ε turbulence model. A multiple frame of reference (MFR) and Sliding Mesh Model have been used to model the multiple impellers and tank region. The effects of specific density of fine-dispersed solid phase and place of injection of solid have been investigated for “steady-state” and time-depended cases.

 

MODELING DESIGN AND ANALYSIS OF MULTI-LAYER SOLID OXIDE FUEL CELLS

R. Hasanov*, A. Smirnova**, A. Gulgazli*, M. Kazimov*, A. Volkov*, V. Quliyeva*, O. Vasylyev***, V.A. Sadykov (*Azerbaijan State Oil Academy, Baku, Azerbaijan; **Eastern Connecticut State University, Willimantic, USA; ***Institute for Problems of Materials Science, Kiev, Ukraine)

Int. J. Hydrogen Energy, 36(2) (2011) pp. 1671-1682.

The thermo-mechanical analytical model proposed for different solid oxide fuel cell (SOFC) designs addresses the deformation behavior and mechanical stability of SOFCs at various thermal stresses, specifically the creep resistance and the long-term endurance beyond the elastic limit.

The model considers the deformation of multi-layer SOFC in the temperature range of 600–800°C and presents the combination of the correlated parameters for SOFC performance evaluation, stability and long-term endurance under realistic operating conditions and temperature gradients. The numerical analysis of the thermo-mechanical properties of the SOFC materials is presented in terms of mechanical behavior at failure conditions and the influence of rheological and structural properties on SOFC long-term endurance. The SOFC thermal behavior, creep parameters of the SOFC materials and long-term stability are analyzed in terms of stresses, deformations and displacements.

In terms of broader impact, the algorithms for Maurice-Levi and Voltaire theorems and their validity for non-elastic, e.g. viscous-elastic, viscous-plastic, and elastic-plastic deformations were confirmed. This result allowed to apply the stress condition of non-elastic body to the stress condition of the elastic body which is relevant to the SOFC operation at elevated temperatures.

ETHYLENE GLYCOL OXIDATION OVER SUPPORTED CATALYST IN TUBULAR REACTOR

M.A. Salaev*, A.A. Krejker*, O.V. Magaev*, V.S. Malkov*, A.S. Knyazev*, E.S. Borisova, V.M. Khanaev, O.V. Vodyankina*, L.N. Kurina*

(*Tomsk State University, Tomsk, Russia)

Chem. Eng. J., 172(1) (2011) pp. 399-409.

Macrokinetics for chemical transformation of ethylene glycol into glyoxal (including side-reactions) as well as 2D heterogeneous mathematical model were suggested. Numerical results obtained using this model were compared with the experimental data obtained at lab-scale and pilot reactor, and showed good correlation. It was shown that due to catalyst activity change it is possible to manage the process selectivity with respect to glyoxal in diffusion mode. The optimal value of catalyst activity providing the highest process selectivity can be found.

SIMULATION OF HETEROGENEOUS CATALYTIC REACTION BY ASYNCHRONOUS CELLULAR AUTOMATA ON MULTICOMPUTER

A.E. Sharifulina*, V.I. Elokhin (*Institute of Computational Mathematics and Mathematical Geophysics, Novosibirsk, Russia)

Lecture Notes Comput. Sci., 6873 (2011) pp. 204-209.

In the paper parallel implementation of ACA simulating dynamics of carbon monoxide oxidation over the Pd(100) is presented. Parallel implementation of ACA is based on its approximation by block-synchronous CA. To estimate approximation accuracy comparative analysis of statistical characteristics and bifurcation diagrams, obtained by ACA and BCSA simulation, is performed. Results of parallel implementation of BSCA algorithm and estimations of its efficiency are presented.

Fuel Chemistry and Technology

DEACTIVATION AND OXIDATIVE REGENERATION OF MODERN CATALYSTS FOR DEEP HYDROPURIFICATION OF DIESEL FUEL: OXIDATIVE REGENERATION OF IC-GO-1 CATALYST

S.V. Budukva, O.V. Klimov, G.S. Litvak, Yu.A. Chesalov, I.P. Prosvirin, T.V. Larina, A.S. Noskov

Russ. J. Appl. Chem., 84(1) (2011) pp. 95-102.

Oxidative regeneration of a deactivated IC-GO-1 catalyst was studied in removal of carbonaceous deposits and sulfur from the catalyst composition. Elemental analysis data, texture characteristics, and catalytic activities of fresh and regenerated samples were compared. Raman spectroscopy, X-ray phase analysis, electronic diffuse reflectance spectroscopy, and X-ray photoelectron spectroscopy were used to examine the structure of cobalt and molybdenum compounds entering into the composition of the catalysts.

HYDROCRACKING OF VACUUM GAS OIL IN THE PRESENCE OF SUPPORTED NICKEL–TUNGSTEN CATALYSTS

A.S. Ivanova, E.V. Korneeva, G.A. Bukhtiyarova, A.L. Nuzhdin, A.A. Budneva, I.P. Prosvirin, V.I. Zaikovsky, A.S. Noskov

Kinet. Catal., 52(3) (2011) pp. 446-458.

The supports containing 70% Al2O3 and 30% β zeolite (AZ-1 and AZ-2), which differed in mixing procedures, and the Ni-W/AZ-1 and Ni-W/AZ-2 catalysts were characterized using an adsorption technique, high-resolution electron microscopy, IR spectroscopy, and X-ray photoelectron spectroscopy and tested in the hydrocracking reaction of vacuum gas oil (VGO). It was found that the supports differed in texture characteristics and surface Lewis acidity at the same composition and similar concentrations of Brønsted acid sites. The formation of Ni-W-S sulfide species on the surfaces of both of the supports occurred in different manners: multilayer Ni-W-S sulfide species were formed on AZ-1 (Ssp = 220 m2/g), whereas single-layer species were mainly formed on AZ-2 (Ssp = 380 m2/g). It was found that catalysts containing multilayer Ni-W-S sulfide species, which were characterized by a higher degree of sulfidation, provided a higher yield of diesel fuel upon the hydrocracking of VGO, whereas catalysts containing single-layer Ni-W-S sulfide species were more active in the reactions of VGO hydrodesulfurization and hydrodenitration.

EFFECT OF THE MOBILITY OF OXYGEN IN PEROVSKITE CATALYST ON THE DYNAMICS OF OXIDATIVE COUPLING OF METHANE

S.I. Reshetnikov, Yu.I. Pyatnitskii*, L.Yu. Dolgikh* (*L.V. Pisarzhevskii Institute of Physical Chemistry, Kyiv, Ukraine)

Theor. Exp. Chem., 47(1) (2011) pp. 49-54.

The effect of the diffusion of oxygen from the volume of the catalyst to its surface on the dynamics of the oxidative coupling of methane was assessed on the basis of a mathematical model of the reaction of methane with the oxidized surface of KNaSrCoO3-x perovskite. It was shown that the possible values of the diffusion coefficient lie in the range of 10-18-10-16 cm2/s characteristic of the diffusion of oxygen in oxide catalysts.

THE STABILITY OF AN ISOTHERMAL GASEOUS SPHERE WITH GRAVITATION

V.N. Snytnikov, O.A. Stadnichenko

Astron. Rep., 55(3) (2011) pp. 214-223.

A dispersion relation has been obtained for waves propagating in an inhomogeneous gas with viscosity and gravity in the direction of the density gradient. It has been shown that a stationary distribution of isothermal gas is unstable under gravitational-convective perturbations. It is suggested that the initial- and boundary-value problems of the non-stationary dynamics of an isothermal gas with gravity but without viscosity are incorrect and require regularization, for example, by adding viscosity. The presence of viscosity does not prevent the development of the Jeans long-wave instability. Numerical experiments based on a fully three-dimensional, non-stationary numerical code have demonstrated the development of a collapse inside an isothermal cloud.

EFFECT OF WATER ON OXIDATIVE SCISSION OF 1-BUTENE TO ACETIC ACID OVER V2O5-TiO2 CATALYST. TRANSIENT ISOTOPIC AND KINETIC STUDY

W. Suprun*, E.M. Sadovskaya, Ch. Rüdinger**, H.-J. Eberle**, M. Lutecki*, H. Papp*

(*Universität Leipzig, Leipzig, Germany; **Wacker Chemie AG, Consortium für Elektrochemische Industrie GmbH, München, Germany)

Appl. Catal. A, 391(1-2) (2011) pp. 125-136.

The role of water in the oxidation of 1-butene to AcOH over VOx-TiO2 was investigated using spectroscopic and transient isotopic exchange methods. It was shown that the influence of water strongly depended on the temperature of reaction. In particular, DRIFTS and NH3-TPD studies confirmed the temperature influence on the acidity and the amount of adsorbed water. XPS investigations suggested that not only oxygen from vanadia, but also from the lattice of titania was involved in the oxygen transfer during the reaction. Formation of oxidation products proceeded over two types of active vanadium oxide centers, i.e., VOH and VO. Hydrated vanadium species exhibited high selectivity towards AcOH formation. On the other hand, VO centers favored total oxidation. Kinetic model was developed for an unambiguous interpretation of the experimental results. Modelled reaction constants of the formation of AcOH over VOH centers were ca. 3.5 times higher than over VO centers. At the same time, the reaction rate constant of total oxidation in the presence of water was ca. 3.2 times lower than in dry flow. Estimated values suggested that in the presence of water the number of VOH centers was substantially lower than VO sites; however their contribution to the rate of AcOH formation was much higher.

INVESTIGATION OF MASS TRANSFER ON GLASS FABRIC CATALYST DURING CO OXIDATION REACTION

О.V. Chub, А.S. Noskov, L.G. Simonova

Chem. Ind. Today, 5 (2011) pp. 19-24.

The mass transfer during CO oxidation reaction has been investigated using Pd-containing catalyst prepared on the basis of glass fabrics of various weaves. The mathematical model of experimental

reactor is formulated. The results are shown in the form of criterial dependency Sh = A Ren Sc1/3, mass transfer coefficients and equation parameters have been determined.

ON А LIMIT EQUATIONS AND ATTRACTION FOR NONAUTONOMOUS SYSTEMS WITH DELAY

I.A. Finogenko*, N.A. Chumakova (*Institute for System Dynamics and Control Theory, Irkutsk, Russia)

Tambov University Reports. Ser.: Nat. Techn. Sci., 16(5) (2011) pp. 1247-1253.

For nonautonomous functional-differential equations property of quasiinvariance for limiting sets and analogue of the La-Salle principle of invariancy by use of Lyapunov functional with constant sign derivative is established.

COMPUTATIONAL FLUID DYNAMICS IN THE DESIGN OF CATALYTIC REACTORS

O.P. Klenov, A.S. Noskov

Catal. Ind., 3(4) (2011) pp. 331-349.

Computational fluid dynamics is becoming an important tool in the study of chemical engineering processes and apparatuses (in particular, the share of works with the application of this method is nearly 6% of the total number of all chemical engineering works issued by Elsevier Science Publishers in 2010). The possibilities of computational fluid dynamics are demonstrated using examples from three different chemical engineering fields: developing a method for loading a tubular reactor for the steam conversion of natural gas, studying heat transfer in a reactor for the hydrogenation of vegetable oils upon the replacement of a catalyst, and investigating the transitional processes in an automobile neutralizer. The results from computational fluid dynamics are verified by comparing them with experimental data in developing a method for loading a tubular reactor, using the problem of decelerating a catalyst particle with a flow of air as an example. The obtained data are compared with classical measurement data on the aerodynamic drag of a ball and a cylinder and represent the further development of works on the flow around particles of complex shape. In this work, the results from inspecting a reactor for the hydrogenation of oils with allowance for the possible heating and uniform distribution of a flow before its entering the catalyst bed are presented. It is shown that the construction of the reactor does not ensure homogeneity of the reaction flow at the desired level and requires modification of heating elements. The efficiency of computational fluid dynamics for investigating fast processes with a chemical reaction is exemplified by studying the transitional processes in an catalytic automobile neutralizer (the effect of flow dynamics and heat transfer on the thermal regime in a honeycomb catalyst particle is very difficult to study by experimental methods). The application of computational fluid dynamics allows us to reduce considerably the time and cost of developing and optimizing the designs of efficient catalytic fixed-, fluidized-, or moving-bed reactors (particularly multiphase stirred (slurry) reactors), along with mixers, adsorbers, bubblers, and other chemical engineering apparatuses with moving media.

SOLID DISPERSION IN THE SLURRY REACTOR WITH MULTIPLE IMPELLERS

O.P. Klenov, A.S. Noskov

Chem. Eng. J., 176-177 (2011) pp. 75-82.

A whole series of significant catalytic processes are carried out in a slurry reactor with multiple impellers. The selective hydrogenation of sunflower seed oil is the characteristic example of such a process. The liquid phase is the main medium into stirred tank and an investigation of a fluid dynamics of one just as transient regime of solid distribution in liquid volume could be helpful to practical application.

In the present work, CFD simulations have been carried out to study solid distribution in liquid–solid stirred tank using Mixture multifluid approach along with standard k-ε turbulence model. A multiple frame of reference (MFR) and Sliding Mesh Model have been used to model the multiple impellers and tank region. The effects of specific density of fine-dispersed solid phase and place of injection of solid have been investigated for “steady-state” and time-depended cases.

MODELING DESIGN AND ANALYSIS OF MULTI-LAYER SOLID OXIDE FUEL CELLS

R. Hasanov*, A. Smirnova**, A. Gulgazli*, M. Kazimov*, A. Volkov*, V. Quliyeva*, O. Vasylyev***, V.A. Sadykov (*Azerbaijan State Oil Academy, Baku, Azerbaijan; **Eastern Connecticut State University, Willimantic, USA; ***Institute for Problems of Materials Science, Kiev, Ukraine)

Int. J. Hydrogen Energy, 36(2) (2011) pp. 1671-1682.

The thermo-mechanical analytical model proposed for different solid oxide fuel cell (SOFC) designs addresses the deformation behavior and mechanical stability of SOFCs at various thermal stresses, specifically the creep resistance and the long-term endurance beyond the elastic limit.

The model considers the deformation of multi-layer SOFC in the temperature range of 600–800°C and presents the combination of the correlated parameters for SOFC performance evaluation, stability and long-term endurance under realistic operating conditions and temperature gradients. The numerical analysis of the thermo-mechanical properties of the SOFC materials is presented in terms of mechanical behavior at failure conditions and the influence of rheological and structural properties on SOFC long-term endurance. The SOFC thermal behavior, creep parameters of the SOFC materials and long-term stability are analyzed in terms of stresses, deformations and displacements.

In terms of broader impact, the algorithms for Maurice-Levi and Voltaire theorems and their validity for non-elastic, e.g. viscous-elastic, viscous-plastic, and elastic-plastic deformations were confirmed. This result allowed to apply the stress condition of non-elastic body to the stress condition of the elastic body which is relevant to the SOFC operation at elevated temperatures.

ETHYLENE GLYCOL OXIDATION OVER SUPPORTED CATALYST IN TUBULAR REACTOR

M.A. Salaev*, A.A. Krejker*, O.V. Magaev*, V.S. Malkov*, A.S. Knyazev*, E.S. Borisova, V.M. Khanaev, O.V. Vodyankina*, L.N. Kurina*

(*Tomsk State University, Tomsk, Russia)

Chem. Eng. J., 172(1) (2011) pp. 399-409.

Macrokinetics for chemical transformation of ethylene glycol into glyoxal (including side-reactions) as well as 2D heterogeneous mathematical model were suggested. Numerical results obtained using this model were compared with the experimental data obtained at lab-scale and pilot reactor, and showed good correlation. It was shown that due to catalyst activity change it is possible to manage the process selectivity with respect to glyoxal in diffusion mode. The optimal value of catalyst activity providing the highest process selectivity can be found.

SIMULATION OF HETEROGENEOUS CATALYTIC REACTION BY ASYNCHRONOUS CELLULAR AUTOMATA ON MULTICOMPUTER

A.E. Sharifulina*, V.I. Elokhin (*Institute of Computational Mathematics and Mathematical Geophysics, Novosibirsk, Russia)

Lecture Notes Comput. Sci., 6873 (2011) pp. 204-209.

In the paper parallel implementation of ACA simulating dynamics of carbon monoxide oxidation over the Pd(100) is presented. Parallel implementation of ACA is based on its approximation by block-synchronous CA. To estimate approximation accuracy comparative analysis of statistical characteristics and bifurcation diagrams, obtained by ACA and BCSA simulation, is performed. Results of parallel implementation of BSCA algorithm and estimations of its efficiency are presented.

Fuel Chemistry and Technology

DEACTIVATION AND OXIDATIVE REGENERATION OF MODERN CATALYSTS FOR DEEP HYDROPURIFICATION OF DIESEL FUEL: OXIDATIVE REGENERATION OF IC-GO-1 CATALYST

S.V. Budukva, O.V. Klimov, G.S. Litvak, Yu.A. Chesalov, I.P. Prosvirin, T.V. Larina, A.S. Noskov

Russ. J. Appl. Chem., 84(1) (2011) pp. 95-102.

Oxidative regeneration of a deactivated IC-GO-1 catalyst was studied in removal of carbonaceous deposits and sulfur from the catalyst composition. Elemental analysis data, texture characteristics, and catalytic activities of fresh and regenerated samples were compared. Raman spectroscopy, X-ray phase analysis, electronic diffuse reflectance spectroscopy, and X-ray photoelectron spectroscopy were used to examine the structure of cobalt and molybdenum compounds entering into the composition of the catalysts.

HYDROCRACKING OF VACUUM GAS OIL IN THE PRESENCE OF SUPPORTED NICKEL–TUNGSTEN CATALYSTS

A.S. Ivanova, E.V. Korneeva, G.A. Bukhtiyarova, A.L. Nuzhdin, A.A. Budneva, I.P. Prosvirin, V.I. Zaikovsky, A.S. Noskov

Kinet. Catal., 52(3) (2011) pp. 446-458.

The supports containing 70% Al2O3 and 30% β zeolite (AZ-1 and AZ-2), which differed in mixing procedures, and the Ni-W/AZ-1 and Ni-W/AZ-2 catalysts were characterized using an adsorption technique, high-resolution electron microscopy, IR spectroscopy, and X-ray photoelectron spectroscopy and tested in the hydrocracking reaction of vacuum gas oil (VGO). It was found that the supports differed in texture characteristics and surface Lewis acidity at the same composition and similar concentrations of Brønsted acid sites. The formation of Ni-W-S sulfide species on the surfaces of both of the supports occurred in different manners: multilayer Ni-W-S sulfide species were formed on AZ-1 (Ssp = 220 m2/g), whereas single-layer species were mainly formed on AZ-2 (Ssp = 380 m2/g). It was found that catalysts containing multilayer Ni-W-S sulfide species, which were characterized by a higher degree of sulfidation, provided a higher yield of diesel fuel upon the hydrocracking of VGO, whereas catalysts containing single-layer Ni-W-S sulfide species were more active in the reactions of VGO hydrodesulfurization and hydrodenitration.

CATALYTIC DEOXYGENATION OF TALL OIL FATTY ACIDS OVER A PALLADIUM-MESOPOROUS CARBON CATALYST: A NEW SOURCE OF BIOFUELS

P. Mäki-Arvela*, B. Rozmysłowicz**, S. Lestari***, O.A. Simakova, K. Eränen*, T. Salmi*, D.Yu. Murzin* (*Åbo Akademi University, Turku, Finland; **Poznan University of Technology, Poznan, Poland; ***University of Queensland, Brisbane, Queensland, Australia)

Energy Fuels, 25(7) (2011) pp. 2815-2825.

Catalytic deoxygenation of tall oil fatty acids (TOFAs) was investigated over 1 wt% Pd/C Sibunit, which is a synthetic mesoporous carbon. The reactions were performed in a semi-batch reactor using dodecane as a solvent under 17 bar of total pressure. The main studied parameters were the reaction temperature, initial concentration of TOFA, effect of the reaction atmosphere, and metal loading. The temperature and initial concentration ranges were 300-350°C and 0.15-0.6 mol/L, respectively. The total conversion of fatty acids increased, as expected, with increasing temperatures and decreasing initial TOFA concentrations. The main liquid-phase products were n-heptadecane and n-heptadecene. In addition to the desired linear C17 hydrocarbons, also aromatic C17 compounds, such as undecylbenzene, were formed. The best conditions for the formation of the desired C17 hydrocarbons were lower initial concentrations of TOFA, 300-325°C, and the presence of hydrogen. An increase of the metal loading (4 wt%) led to an increase of the selectivity to linear C17 hydrocarbons.

CATALYTIC DEOXYGENATION OF C18 FATTY ACIDS OVER MESOPOROUS Pd/C CATALYST FOR SYNTHESIS OF BIOFUELS

I.L. Simakova, B. Rozmysłowicz*, O.A. Simakova, P. Mäki-Arvela*, A. Simakov**, D.Yu. Murzin*

(*Abo Akademi University, Turku, Finland; **Centro de Nanociencias y Nanotecnología, UNAM, Ensenada, BC, México)

Top. Catal., 54(8-9) (2011) pp. 460-466.

Deoxygenation was systematically investigated using either stearic, oleic or linoleic acids as a feedstock at 300°C under 1 vol% hydrogen in argon over a mesoporous Pd/C (Sibunit) catalyst producing one less carbon containing, diesel-like hydrocarbons.

The results revealed that catalyst activity and selectivity increased with less unsaturated feedstock. The main products in the case of stearic acid were desired C17 hydrocarbons, whereas the amounts of C17 aromatic compounds increased in case of oleic and linoleic acids. Catalyst deactivation was relatively prominent in linoleic acid deoxygenation giving only 3% conversion of fatty acids in 330 min. The deactivation originated from the formation of C17 aromatic compounds and fatty acid dimers, which was confirmed by size exclusion chromatographic analysis. The latter compounds were formed via Diels-Alder reaction.

CATALYSIS IN BIOMASS PROCESSING

D.Yu. Murzin*, I.L. Simakova (*Åbo Akademi University, Turku, Finland)

Catal. Ind., 3(3) (2011) pp. 218-249.

Biomass has in recent years been considered as a raw material for the production of fuels and chemicals. This work discusses the reasons for the increased interest in mainly lignocellulosic biomass. Gasification, pyrolysis, and depolymerization by hydrolysis are analyzed as key biomass technology. The authors also discuss which of the sugars obtained via depolymerization by hydrolysis can be processed into fuel or key intermediates of the chemical industry. Lignocellulosic biomass contains such extractants as fatty acids and terpenes, and the authors therefore describe the catalytic reactions of these substances for the synthesis of fuels and chemicals. Some typical reactions of biomass processing (oxidation, hydrogenation, cracking, etc.) are conceptually close to the process widely known in the refining and chemical industries. There are, however, other considerations due to, e.g., the large number of functional (hydroxyl and other) groups, and the processing of biomass components therefore requires dehydration, aldol condensation, ketonization, decarboxylation, etc. The authors cover the fundamentals of the approaches to selecting catalysts for these reactions.

METHANE CONVERSION TO VALUABLE CHEMICALS OVER NANOSTRUCTURED Mo/ZSM-5 CATALYSTS

Z.R. Ismagilov, E.V. Matus, M.A. Kerzhentsev, L.T. Tsykoza, I.Z. Ismagilov, K.D. Dosumov*, A.G. Mustafin** (*Sokol’skii Institute of Organic Catalysis and Electrochemistry, Almaty, Republic of Kazakhstan; **Bashkir State University, Ufa, Russia)

Pet. Chem., 51(3) (2011) pp. 174-186.

Results of the ongoing study of nonoxidative methane dehydroaromatization (DHA) over Mo/ZSM-5 catalysts have been analyzed. The effects of the composition, preparation procedure, pretreatment, and the CH4 DHA reaction conditions on the physicochemical and catalytic properties of Mo/ZSM-5 catalysts have been discussed. The data on Mo-containing active sites, the methane DHA reaction mechanism, and the nature of carbonaceous deposits have been considered. The principal causes of the deactivation of Mo/ZSM-5 catalysts and means of their regeneration have been revealed. Approaches to the improvement of the methane DHA process and trends of its further development have been detailed.

OXIDATIVE DESULFURIZATION OF HYDROCARBON FUELS

Z.R. Ismagilov, S.A. Yashnik, M.A. Kerzhentsev, V.N. Parmon, A. Bourane*, F.M. Al-Shahrani*, A.A. Hajji*, O.R. Koseoglu* (*Saudi Aramco, Research and Development Center, Dhahran, Kingdom of Saudi Arabia)

Catal. Rev. - Sci. Eng., 53(3) 2011) pp. 199-255.

New requirements for very low sulfur content (10 ppm) in liquid motor fuels demand novel approaches for ultra-deep desulfurization. For production of near-zero-sulfur diesel and low-sulfur fuel oil, removal of refractory sulfur compounds, like 4,6-dimethyldibenzothiophene and other alkyl-substituted thiophene derivatives, is necessary. Elimination of these compounds by hydrodesulfurization (HDS) requires high hydrogen consumption, high pressure equipment, and new catalysts. Various oxidative desulfurization processes, including recent advances in this field for diesel fuels, and the drawbacks of this technology in comparison with HDS are examined and discussed. It is shown that the oxidation of sulfur compounds to sulfones with hydrogen peroxide allows for production of diesel fuels with a sulfur content of 10 ppmw or lower at atmospheric pressure and room temperature. The gas phase oxidative desulfurization of sulfur compounds with air or oxygen is feasible at atmospheric pressure and higher temperatures: 90–300°С and offers better economic solutions and incentives.

CARBON DIOXIDE REFORMING OF METHANE OVER Со-Ni CATALYSTS

G.B. Aldashukurova*, A.V. Mironenko*, Z.A. Mansurov*, N.V. Shikina, S.A. Yashnik, Z.R. Ismagilov (*Institute for Problems of Combustion, Almaty, Kazakhstan)

Chem. Eng. Trans., 25 (2011) pp. 63-68.

Low-percentage catalysts for dry reforming of methane (DRM) with Ni and Co deposited on a glass fiber support by the “solution combustion” (SC) method have been developed. Particle size and state of the active component were studied by XRD, TPR, TEM, SEM and AFM. The active component was shown to be dispersed in the near-surface layer of support as nanoparticles of size 10–20 nm, which have a Co3O4 or (Co,Ni)Co2O4 spinel structure depending on the catalyst composition. Spinel structure of the active component is resistant to carbonization and provides high catalytic activity toward DRM.

HETEROGENEOUS CATALYSTS FOR THE TRANSFORMATION OF FATTY ACID TRIGLYCERIDES AND THEIR DERIVATIVES TO FUEL HYDROCARBONS

V.A. Yakovlev, S.A. Khromova, V.I. Bukhtiyarov

Russ. Chem. Rev., 80(10) (2011) pp. 911-925.

The results of studies devoted to the catalysts for transformation of fatty acid triglycerides and their derivatives to fuel hydrocarbons are presented and described systematically. Various approaches to the use of heterogeneous catalysts for the production of biofuel from these raw materials are considered. The bibliography includes 134 references.

PYROLYSIS OF RAPIDLY GROWING GRASS BIOMASS UNDER ISOTHERMAL CONDITIONS

S.G. Zavarukhin, I.A. Streltsov, V.A. Yakovlev

Kinet. Catal., 52(4) (2011) pp. 499-505.

The pyrolysis of rapidly growing grass biomass in an inert atmosphere was studied by thermogravimetric analysis using sorghum as an example. Pyrolysis was performed under isothermal conditions at temperatures from 250 to 400°C. To describe the reaction kinetics, a single-component model including six first-order reactions was proposed. A special feature of this model is the occurrence of a step of the formation of an intermediate carbonaceous substance from the volatile products of biomass decomposition

PRODUCTION OF BIODIESEL FORM RAPESEED OIL USING HETEROGENEOUS Ba-Al CATALYST IN THREE-PHASE REACTOR

S.G. Zavarukhin, M.Yu. Lebedev, A.N. Simonov, L.G. Matvienko, A.S. Ivanova, V.N. Parmon, V.G. Sister*, O.V. Sherstyuk, M.V. Bukhtiyarova, V.A. Yakovlev (*Moscow State University of Ecological Engineering)

Chem. Ind. Today, 10 (2011) pp. 14-22.

The production of biodiesel by transesterification of rapeseed oil using methanol and heterogeneous BaAl catalyst was studied in three-phase reactor. Simplified kinetic model of transesterification process was proposed and the catalyst volume was calculated for the industrial reactor with the performance 2250 kg/hour of oil with oil conversion 95 %.

POROUS NICKEL BASED CATALYSTS FOR PARTIAL OXIDATION OF METHANE TO SYNTHESIS GAS

V.A. Kirillov, Z.A. Fedorova, M.M. Danilova, V.I. Zaikovsky, N.A. Kuzin, V.A. Kuzmin, T.A. Krieger, V.D. Meshcheryakov

Appl. Catal. A, 401(1-2) (2011) pp. 170-175.

The phase composition and texture of nickel catalysts supported on ribbon porous nickel with a magnesium oxide underlayer were investigated by X-ray diffraction, low-temperature nitrogen adsorption, and electron microscopy combined with energy dispersive X-ray microanalysis. The MgO underlayer was obtained by impregnation the porous nickel with a Mg(NO3)2 solution followed by calcination at 550°C; nickel was supported additionally by impregnation with a Ni(NO3)2 solution followed by calcination at 450°C. In the supported reduced nickel catalysts (800-900°C, H2) the phases of Ni and a solid solution of NiO in MgO were observed; a considerable part of nickel crystallites was epitaxially bound with MgO. The partial oxidation of methane to synthesis gas (800°C, O2/C = 0.65, GHSV = 127 L/g h) over porous nickel based catalysts was studied. The activity of initial nickel support decreased considerably during the partial oxidation of methane; the value of methane conversion decreased slightly after 100 h of testing on the supported nickel catalysts.

Chemical Engineering

EFFECT OF INTERNAL DIFFUSION ON PREFERENTIAL CO OXIDATION IN A HYDROGEN-RICH MIXTURE ON A COPPER-CERIUM OXIDE CATALYST IN A MICROCHANNEL REACTOR

D.I. Potemkin, P.V. Snytnikov, V.D. Belyaev, V.A. Sobyanin

Kinet. Catal., 52(1) (2011) pp. 139-144.

The effect of internal diffusion on preferential CO oxidation in a hydrogen-rich mixture on a copper-cerium catalyst in a microchannel reactor was estimated. It was found that the internal effectiveness factor ηCO > 0.8 was reached at a catalytic coating thickness of ∼30 μm.

PREFERENTIAL CO OXIDATION OVER Cu/CeO2x CATALYST: INTERNAL MASS TRANSPORT LIMITATION

D.I. Potemkin, P.V. Snytnikov, V.D. Belyaev, V.A. Sobyanin

Chem. Eng. J., 176-177 (2011) pp. 165-171.

The effect of internal mass transport limitation on the preferential CO oxidation in hydrogen-rich mixture over copper-cerium oxide catalyst in a form of pellets and washcoat in microchannel reactor is estimated. Internal effectiveness factor r|CO >0.8 in the optimum interval of reaction temperature (170-230°C) is reached if the pellet diameter and washcoat thickness do not exceed 100 and 20 цm, respectively.

Compared to conventional packed-bed reactor with catalyst pellets, microchannel catalytic washcoated reactor is more appropriate for practical use.

TECHNIQUE FOR COMPLETE OXIDATION OF ORGANIC COMPOUNDS IN SUPERCRITICAL WATER

V.I. Anikeev, An. Yermakova

Russ. J. Appl. Chem., 84(1) (2011) pp. 88-94.

Results are presented of tests of a pilot stationary installation for supercritical water oxidation of organic compounds, first created in Russia. A high oxidation efficiency of nitro compounds formed as waste in manufacture of explosives is demonstrated.

APPLICATION OF SYNTHESIS GAS AS A FUEL ADDITIVE ONBOARD THE VEHICLE: STATE OF THE ART AND PROSPECTS

V.N. Parmon, V.A. Kirillov, V.A. Sobyanin, V.A. Burtsev*, V.K. Emel’yanov**, N.A. Kuzin, V.V. Kireenkov, Yu.I. Amosov

(*OOO Gasomotor-R, Rybinsk, Yaroslavl oblast, Russia; **International Science and Technology Center, Moscow, Russia)

Theor. Found. Chem. Eng., 45(2) (2011) pp. 127-140.

A method for the production of a hydrogen-rich gas on board a vehicle was suggested and driving- and bench-tested for application in studies on energy-efficient internal combustion engines with minimum CO, CO2, CH, and NOx emissions. The generated gas is further added to the main fuel fed to the engine. Catalysts for hydrocarbon fuel conversion to syngas were developed. A compact on-board syngas generator mounted under the motor hood and a generator control system adapted to the engine control system were designed. It was shown experimentally that the suggested solution allows a reduction of 13– 40% in the fuel rate depending on the operating mode under the urban cycle conditions and considerably decreases the release of CO, CO2, and NOx. Prospects for the applications of this technology for creating ecologically clean engines were assessed.

CATALYSTS FOR THE CONVERSION OF HYDROCARBON AND SYNTHETIC FUELS FOR ONBOARD SYNGAS GENERATORS

V.A. Kirillov, N.A. Kuzin, Yu.I. Amosov, V.V. Kireenkov, V.A. Sobyanin

Catal. Ind., 3(2) (2011) pp. 176-182.

The use of syngas derived on board a vehicle as a supplement to the main fuel fed to engines ensures engine operation using dilute fuel mixtures. This leads to a decrease in emission toxicity and an increase in the fuel efficiency of the engine. The preparation of new types of efficient catalysts for the conversion of hydrocarbon and synthetic fuels for onboard syngas generators requires the use of new approaches to the design of catalysts not only as catalytically active material, but also as a structural component of a chemical reactor. The authors prepared and tested a set of catalysts for the conversion of hydrocarbons, i.e., natural gas, diesel and biodiesel fuels, biofuels, and alcohols (ethanol, methanol) to syngas. Primary supports for the catalysts were metals grids and porous tapes; secondary supports were oxides of aluminum and magnesium deposited on or sintered to a primary support. The catalysts exhibited high thermal stability and mechanical strength, and were characterized by the conformity of the coefficients of thermal expansion of the support material and the catalytically active bed. The catalysts can be used as structural components of reactors and as a basis for the preparation of monolithic blocks and planar components of radial and planar reactors. The developed catalysts were subjected to laboratory and bench tests and examined as components of onboard generators of vehicles.

USE OF Pd MEMBRANES IN CATALYTIC REACTORS FOR STEAM METHANE REFORMING FOR PURE HYDROGEN PRODUCTION

A.B. Shigarov, V.D. Meshcheryakov, V.A. Kirillov

Theor. Found. Chem. Eng., 45(5) (2011) pp. 595-609.

This review analyzes publications on experimental studies and mathematical modeling in the field of development of a catalytic reformer (mainly, steam methane conversion) with a fixed catalytic bed. The specific feature of such a reformer is its integration with a Pd membrane for the purpose of producing high-purity hydrogen to power a low-temperature fuel cell battery.

DESIGN, SCALE-OUT, AND OPERATION OF A PREFERENTIAL CO METHANATION REACTOR WITH A NICKEL–CERIA CATALYST

M.M. Zyryanova, P.V. Snytnikov, Yu.I. Amosov, V.A. Kuzmin, V.A. Kirillov, V.A. Sobyanin

Chem. Eng. J., 176-177 (2011) pp. 106-113.

Preferential CO methanation in a reformate gas was investigated over 10 wt% Ni/CeO2 pelleted catalyst in the fixed-bed reactor. It provided the reduction of the CO concentration in the reformate gas to less than 10 ppm over wide temperature interval (250–300°C), while keeping hydrogen consumption relatively low.

The design, scale-out, and operation of a preferential CO methanation reactor with integrated heatexchanger were reported. The nickel–ceria catalyst was deposited onto metal gauzes, assembled into catalytic blocks. Direct contact of the catalyst with metal support provided high heat conductivity of the assembly and feasible temperature control upon variation of operation regimes. Nickel–ceria catalyst showed high activity and selectivity for the reaction of CO methanation in the presence of CO2 excess. The preferential CO methanation reactor allowed the decrease of CO concentration to less than 20 ppm in realistic reformate generated by fuel processor via the reaction of methane steam reforming followed by CO water gas shift reaction.

SORPTION PROPERTIES OF LITHIUM CARBONATE DOPED CaO AND ITS PERFORMANCE IN SORPTION ENHANCED METHANE REFORMING

V.S. Derevshchikov, A.I. Lysikov, A.G. Okunev

Chem. Eng. Sci., 66(13) (2011) pp. 3030-3038.

In-house prepared lithium carbonate doped CaO was tested for its CO2 sorption properties and suitability as a CO2 sorbent for sorption-enhanced reforming of methane. The new material demonstrated CO2 capacity at the temperatures above the equilibrium for CaO recarbonation reaction. However, the capacity was unstable and decreased during carbonation–regeneration cycles. After sufficiently large number of cycles Li dopant escaped from the sorbent and its sorption behavior resembled to that of CaO. The main route of escape is, probably, a

crossover of liquid Li2CO3 onto crucible in TG experiments and onto catalyst in SER tests. Sorption enhanced methane reforming at 2 bar pressure, 750°C and H2O to CH4 ratio of 4 using novel sorbent yielded as high as 99.8 vol% pure hydrogen during the first cycle. In subsequent cycles the hydrogen purity drastically decreased as a result of severe catalyst poisoning by Li.

HIGH TEMPERATURE CaO/Y2O3 CARBON DIOXIDE ABSORBENT WITH ENHANCED STABILITY FOR SORPTION-ENHANCED REFORMING APPLICATIONS

V.S. Derevshchikov, A.I. Lysikov, A.G. Okunev

Ind. Eng. Chem. Res., 50(22) (2011) pp 12741-12749.

To improve the stability of high temperature CO2 absorbent for sorption enhanced reforming applications yttria supported CaO were synthesized using two methods: calcination of mixed salt precursors and wet impregnation of yttria support. According to XRD data, CaO does not interact with the yttria matrix. However, introduction of CaO drastically changes the morphology of primary yttria particles. Increase in CaO concentration results in gradual plugging of the smaller pores and sintering of yttria support. The CO2 absorption uptake in recarbonation-decomposition cycles increases with increase in CaO content and reach 9.6 wt% at CaO content of 19.9 wt%. CaO recarbonation extent varies from 49 to 77%. CaO/Y2O3 absorbents are extremely stable under overheating and maintain their capacity in long series of decomposition-recarbonation cycles even after calcination at 1350°C. The novel material resists moisture and retains its strength during storage in the air. According to tests, CaO/Y2O3 can be considered as a promising CO2 absorbent for fixed bed sorption enhanced hydrocarbons reforming.

EFFECT EXERTED BY TEXTURE OF CALCINED CALCIUM OXIDE ON ITS SORPTION CAPACITY IN THE CO2 SORPTION-REGENERATION CYCLES

A.G. Okunev, A.I. Lysikov

Russ. J. Appl. Chem., 84(2) (2011) pp. 173-178.

The dynamic capacity of a set of sorbents prepared by calcination of different precursors was studied in multiple CO2 sorption-regeneration cycles.

The effect exerted by type of a precursor and calcination temperature on the steady state value of the dynamic capacity attained after several tens of cycles was determined. A model was suggested for estimate of the sorption capacity of CaO sintered above the Tammann temperature from data on the mercury porosimetry.

PROMISING CHEMICAL ADSORPTION CYCLIC PROCESSES FOR СО2 ISOLATION FROM SMOKE FUMES

A.G. Okunev, A.I. Lysikov

Chem. Sustain. Devel., 19(1) (2011) pp. 105-112.

Promising cyclic processes of hydrocarbon combustion distinguished by the type of the chemisorbent used are considered. In the carbonate cycle, solid high-temperature regenerable chemisorbent for СО2 is used to isolate carbon dioxide. In the oxygen cycle, a solid chemisorbent of oxygen is used; it gets recovered when in contact with fuel and gets oxidized when in contact with the air. A common feature of these processes includes solid-phase reactions of binding and release of the products or reagents at different stages of the process. Requirements to chemisorbents for cyclic processes are determined. Various factors affecting the efficiency of their use are considered, literature data on the efficiency of the proposed cycles of СО2 concentrating are reported.

PROTON CONDUCTING HYDROCARBON MEMBRANES: PERFORMANCE EVALUATION FOR ROOM TEMPERATURE DIRECT METHANOL FUEL CELLS

I.M. Krivobokov, E.N. Gribov, A.G. Okunev

Electrochim. Acta, 56(5) (2011) pp. 2420-2427.

The methanol permeability, proton conductivity, water uptake and power densities of direct methanol fuel cells (DMFCs) at room temperature are reported for sulfonated hydrocarbon (sHC) and perfluorinated (PFSA) membranes from Fumatech®, and compared to Nafion® membranes. The sHC membranes exhibit lower proton conductivity (25–40 mS cm-1 vs. ∼95–40 mS cm-1 for Nafion®) as well as lower methanol permeability (1.8–3.9 × 10-7 cm2 s-1 vs. 2.4-3.4 × 10-6 cm2 s-1 for Nafion®). Water uptake was similar for all membranes (18–25 wt%), except for the

PFSA membrane (14 wt%). Methanol uptake varied from 67 wt% for Nafion® to 17 wt% for PFSA. The power density of Nafion® in DMFCs at room temperature decreases with membrane thickness from 26 mW cm-2 for Nafion® 117 to 12.5 mW cm-2 for Nafion® 112. The maximum power density of the Fumatech® membranes ranges from 4 to 13 mW cm-1. Conventional transport parameters such as membrane selectivity fail to predict membrane performance in DMFCs. Reliable and easily interpretable results are obtained when the power density is plotted as a function of the transport factor (TF), which is the product of proton concentration in the swollen membrane and the methanol flux. At low TF values, cell performance is limited by low proton conductivity, whereas at high TF values it decreases due to methanol crossover. The highest maximum power density corresponds to intermediate values of TF.

PYROLYSIS OF LIQUID HEXADECANE WITH SELECTIVE MICROWAVE HEATING OF THE CATALYST

E.I. Udalov, V.A. Bolotov, Yu.Yu. Tanashev, Yu.D. Chernousov*, V.N. Parmon (*Institute of Chemical Kinetics and Combustion, Novosibirsk, Russia)

Theor. Exp. Chem., 46(6) (2011) pp. 384-392.

The pyrolysis of liquid n-hexadecane was studied on various catalysts with selective microwave (MW) heating of a catalyst possessing much greater microwave absorption capacity than the long-chain hydrocarbon studied. This method permits rapid heating of the catalyst to temperatures much higher than 400°C, leading to reflux of the liquid substrate, movement of the catalyst granules within the substrate, and chemical transformations (cracking) of hexadecane. High pyrolysis selectivity relative to α-olefins was found on various catalysts such as magnetic microspheres (coal combustion ash), Al2O3/Al, and Pd/KTP (glass fiber). This behavior may be attributed to tempering of the primary products in the bulk of the liquid reagent. Furthermore, MW pyrolysis on magnetic microspheres was found to be accompanied by formation of rather thick carbon microfibers with diameter 300-500 nm.

ANALYSIS OF THE DEACTIVATION OF CLAUS ALUMINA CATALYST DURING ITS INDUSTRIAL EXPLOITATION

P.N. Kalinkin, O.N. Kovalenko, O.I. Platonov* (*Gipronickel Institute, LTD, St. Petersburg, Russia)

Catal. Ind., 3(2) (2011) pp. 183-188.

Change in the activity of AO-NKZ-2 (AO-MK-2) alumina catalyst in the Claus reaction and transformations of carbonyl sulfide during operation over four years in the Claus reactor at the Magnitogorsk Metallurgical Combine’s coke-oven gas purification shop were studied at an average temperature of 245–260°C and a volume velocity of ~2000 h–1. The rate constants of the Claus reactions and COS transformation were determined, and the changes in the active surface area of the catalyst were investigated. Fundamental discrepancies in the rate and deactivation mechanism of the Claus catalysts were revealed with respect to the reactions of the conversion of hydrogen sulfide and carbonyl sulfide.

SELECTION OF MODIFYING ADDITIVES FOR IMPROVING THE STEAM TOLERANCE OF METHANE AFTERBURNING PALLADIUM CATALYSTS

M.A. Mashkovtsev*, A.K. Khudorozhkov, I.E. Beck, A.V. Porsin, I.P. Prosvirin, V.N. Rychkov*, V.I. Bukhtiyarov (*Ural Federal University, Yekaterinburg, Russia).

Catal. Ind., 3(4) (2011) pp. 350-357.

In this work, the authors discuss the problem of the afterburning of methane from the exhaust gases of automobile engines fueled by natural gas. In exhaust neutralizers, the PdO/Al2O3 catalyst, the main drawback of which is the reduction of its activity under the action of steam that always present in exhaust gases, is commonly used. To improve the tolerance to steam, a series of PdO-MexOy /Al2O3 binary catalysts (Me is Co, Cu, Fe, Ni, Mn, or Sn) was prepared and studied. Comparative tests under conditions modeling the methane afterburning process in automobile neutralizers show that Pd catalysts promoted with nickel, cobalt, and tin oxides are more resistant to the inhibiting action of steam. The high crystallinity of supported PdO and its uniform distribution over the surface of modified Al2O3 are indicated as criteria for the stability of catalysts in the presence of steam. Optimization of the concentration of promotors and the preparation method used for their introduction allows the deactivation of Pd catalysts under the action of steam to be almost completely eliminated.

CATALYTIC TECHNOLOGIES BASED ON APPLICATION OF GLASS-FIBER CATALYSTS

A.N. Zagoruiko, B.S. Bal’zhinimaev

Chem. Ind. Today, 2 (2011) pp. 2-11.

Engineering questions of catalytic technologies based on application of new generation of catalysts on glass-fiber carriers are discussed.

MICROCHANNEL CATALYTIC SYSTEMS FOR THE INTENSIFICATION OF HYDROGEN PRODUCTION FROM CARBON-CONTAINING FEEDSTOCKS

L.L. Makarshin, V.N. Parmon

Catal. Ind., 4(1) (2012) pp. 27-38.

In the early 1990’s, the progress in modern microelectronic technologies gave an impetus to studies of specific behavior of microchannel systems in various physicochemical processes. The microchannel systems were shown, with heat exchangers, mixers and microchannel reactors (microreactors) as examples, to intensify all the processes in the microchannels. In the present review paper, principal criteria, that make possible to classify a flow system as the microchannel one, are discussed. Three main catalytic processes – steam conversion, partial oxidation and autothermal conversion of light hydrocarbons and alcohols into hydrogen-containing gas – are considered and analyzed. It is shown with methane and methanol as examples that the process of hydrogen generation is enhanced indeed in the microreactor. In steam conversion of methanol catalyzed by Zn/TiO2 at 450°C, the specific hydrogen productivity per catalyst weight was as high as 78,6 L/(h·gcat), the outlet quantity of carbon monoxide being no more than 1 mol.%. In partial oxidation of methane over catalyst La0,2Zr0,4Ce0,4/LaNiPt (0,48 g) in a microreactor at 700°C, the specific hydrogen productivity was 521 L/(h·gcat) per catalyst weight and 42 L/(h·cm3) per reaction zone volume. When so, the thermal capacity (heat generated at hydrogen combustion) is 117 kW for the microreactor with 1,0 dm3 reaction volume that is comparable to the power of the gasoline engine of a modern vehicle. Hydrogen production from bioethanol, gasoline and diesel fuel also seems promising. Inspection of relevant literature in the field demonstrated that these fuels can compete successfully with methanol and methane, even though the catalytic conversion proceeds at temperatures 650°C or higher. Results obtained in developing fuel cell – catalytic generators of hydrogen-containing gas with a low content of carbon monoxide (less than 20 ppm) – are reported in the last Section. Integrated microchannel systems are shown to be the most promising fuel cells.

CATALYTIC PARTIAL OXIDATION OF METHANE IN MICROCHANNEL REACTORS WITH CO-CURRENT AND COUNTERCURRENT REAGENT FLOWS: AN EXPERIMENTAL COMPARISON

L.L. Makarshin, D.V. Andreev, A.G. Gribovskii, V.N. Parmon

Chem. Eng. J., 178(15) (2011) pp. 276-281.

Microchannel catalytic reactors have repeatedly proved their high efficiency in the process of partial oxidation of methane (POM) as compared to traditional fixed-bed catalytic reactors. However, a serious problem of the microchannel reactor operation at this process appears to be high thermal power evolved on the narrow front edge of the microchannel (MC) plates. As a result, the front edge of the plates may undergo thermal corrosion and destruction during the POM process. The way out is to develop microchannel plates, which design would provide a countercurrent reagents flow inside the reactors. A comparison of the operation of microchannel reactors using co-current and countercurrent reagent flows shows substantial advantages of the latter. At high and prolong heating load, a microchannel reactor with the countercurrent reagent flow (MCR-Z) outperforms a reactor with the co-current reagent flow (MCR-P) both in the methane conversion and carbon monoxide selectivity. This is associated with the lower temperature of the front edge of the microchannel plate as well as the lower inner temperature gradient in the MCR-Z in comparison to the MCR-P. Thus, the countercurrent flow scheme allows solving some serious problems of corrosion and destruction of the microchannel plate front edge at high heat loads during the POM process.

USING CATALYSTS BASED ON MOLYBDENUM AND TUNGSTEN CARBIDES IN THE WATER-GAS SHIFT REACTION

G.L. Semin, A.R. Dubrovsky*, P.V. Snytnikov, S.A. Kuznetsov*, V.A. Sobyanin (*Tananaev Institute of Chemistry and Technology of Rare Elements and Mineral Raw Materials, Murmansk Region, Apatity, Russia)

Catal. Ind., 4(1) (2012) pp. 59-66.

The review presents data on the main areas of application of molybdenum and tungsten carbides as catalysts for several industrially important reactions and the basic solutions for the synthesis of catalysts. Some of these methods can be considered as the initial phase of technology development of industrial catalysts based on molybdenum and tungsten carbides. The greatest prospect as a catalyst in the CO conversion by water vapor have a composition based on Mo2C.

ECOLOGICAL AND ENERGY ASPECTS OF THE PROPANE DEHYDROGENATION PROCESS REALIZED IN THE MEMBRANE REACTOR

E.V. Shelepova, A.A. Vedyagin

Alternative Energy Ecol., 2 (2011) pp. 98-101.

The both energy and ecological aspects of propylene production in the membrane reactor were analyzed. An approach considering the simultaneous occurrence of the thermodynamically conjugated reactions in the membrane reactor has been suggested and theoretically realized. Such method allows one to reduce the contribution of side reactions due to shifting the equilibrium of the propane dehydrogenation reaction towards formation of propylene. The effect of hydrogen oxidation in the membrane reactor upon the propane conversion has been studied. It was shown that the heat of hydrogen oxidation reaction allows one to minimize energy operating costs for the process of propane dehydrogenation.

KINETICS OF PHENOL HYDROGENATION OVER Pd-CONTAINING HYPERCROSSLINKED POLYSTYRENE

E.M. Sulman*, A.A. Ivanov, V.S. Chernyavskii, M.G. Sulman*, A.I. Bykov*, A.I. Sidorov*, V.Yu. Doluda*, V.G. Matveeva*, L.M. Bronstein**, B.D. Stein**, A.S. Kharitonov

(*Tver Technical University, Tver, Russia; **Indiana University, Bloomington, IN, USA)

Chem. Eng. J., 176-177 (2011) pp. 33-41.

Hypercrosslinked polystyrene (HPS) has been used as a support for preparation of the palladium-based catalyst, Pd/HPS, for gas phase hydrogenation of phenol to cyclohexanone. At the phenol conversion 99%, the catalyst provides selectivity for ketone not lower than 95 mol%. The Pd/HPS catalyst showed high stability, retaining its catalytic performance at least for 20 days. Kinetics was used to compare Pd/HPS with the commercial Pd/Al2O3 catalyst. The catalytic efficiency was assessed using the derived dimensionless kinetic equation without a ‘time’ parameter. Three major reaction routes with their rate parameters and activation energies were revealed. From kinetic parameters, the maximum possible yield of cyclohexanone in the temperature range of 120– 180°C was determined. The important feature of the Pd/HPS catalyst is that selectivity is independent of the temperature at a certain phenol conversion. At elevated temperatures (160–180°C), the selectivity is at least 2–3% higher as compared to the commercial catalyst Pd/Al2O3, which makes Pd/HPS largely promising for industrial applications.

DEHYDROGENATION OF PROPANE–ISOBUTANE MIXTURE IN A FLUIDIZED BED REACTOR OVER Cr2O3/Al2O3 CATALYST: EXPERIMENTAL STUDIES AND MATHEMATICAL MODELLING

N.V. Vernikovskaya, I.G. Savin*, V.N. Kashkin, N.A. Pakhomov, An. Yermakova,

V.V. Molchanov, E.I. Nemykina, O.A. Parahin** (*JSC “Tobolsk-Neftehim”, Tobolsk, Russia; **JSC “NPK Sintez”, Barnaul, Russia)

Chem. Eng. J., 176-177 (2011) pp. 158-164.

An influence of propane addition to the inlet feed on the performance of industrial fluid bed reactor for isobutane dehydrogenation was experimentally and numerically studied. Experiments on dehydrogenation of propane–isobutane mixture in a pilot fluidized and

in a lab fixed bed reactors were performed over Cr2O3/Al2O3 industrial catalyst. Adding C3H8 to the reactor inlet was found to increase experimental conversion of C3–C4 mixture and the total process selectivity to olefins. Results of the mathematical modelling of the industrial-scale fluidized bed reactor show some benefits of C3H8 addition. Selectivity to i-C4H8 was found to be high enough and grows slightly from 86 to 89% on increasing inlet C3H8 fraction from 0 to 60 wt%. Inlet concentrations of C3H8 up to 20 wt% lead to the apparent selectivity to C3H6 exceeding 100%. Coke yield rises slowly allowing safe industrial fluid bed reactor operation.

CATALYTIC DEHYDRATION OF BIOETHANOL TO ETHYLENE: PILOT-SCALE STUDIES AND PROCESS SIMULATION

A.P. Kagyrmanova, V.A. Chumachenko, V.N. Korotkikh, V.N. Kashkin, A.S. Noskov

Chem. Eng. J., 176-177 (2011) pp. 188-194.

Process of bioethanol dehydration to ethylene over alumina-based catalyst in tubular fixed bed reactor was studied both experimentally and numerically. Kinetic studies were carried out to determine the reaction network, to estimate the parameters of the kinetic model and to find the optimal conditions that provide the maximal ethylene yield in the reaction of bioethanol dehydration. Pilot scale studies and process simulation were carried out to determine the optimal technological regimes in a single catalyst tube as an element of a multi-tubular reactor. The optimal characteristics and process parameters of industrial tubular fixed bed reactor for ethylene production from bioethanol at capacity of 60,000 TPA have been determined.

INFLUENCE OF ADDITIVES IN THE BATCH ON BENZOPYRENE EMISSION DURING THE PRODUCTION OF ANODIC CARBON AND GRAPHITE

Ch.N. Barnakov*, A.P. Kozlov*, V.I. Malysheva*, Z.R. Ismagilov, V.F. Anufrienko, V.N. Parmon

(*Institute of Coal-Chemistry and Material Science, Kemerovo, Russia)

Coke Chem., 54(7) (2011) pp. 241-243.

The influence of various additives to the initial batch on benzopyrene emissions is investigated, both in the production of self-sintering anodes and in the

formation of green anodes for graphite production. Benzopyrene is bound in the presence of transition-metal compounds at 600–1000°C.

A CAPILLARY GAS CHROMATOGRAPHIC COLUMN WITH A POROUS LAYER BASED ON THE DIVINYLBENZENE-VINYLIMIDAZOLE COPOLYMER

O.A. Nikolaeva, Yu.V. Patrushev, V.N. Sidelnikov

Russ. J. Phys. Chem. A, 85(9) (2011) pp. 1647-1651.

Capillary columns with a new sorbent based on the divinylbenzene-vinylimidazole organic copolymer are proposed. The properties of the prepared columns are discussed. It is demonstrated that columns based on the divinylbenzene-vinylimidazole polymer with different selectivities can be prepared by varying the relative amount of vinylimidazole in the initial polymerization mixture. The examples of separation of light hydrocarbons, permanent gases, and oxygen-containing compounds are given.

LIQUID-PHASE DECHLORINATION OF TOXIC TECHNOGENIC PRODUCTS USING NANO-DISPERSED PALLADIUM CATALYSTS BASED ON SIBUNIT

A.V. Mekhaev*, M.G. Pervova*, O.P. Taran, I.L. Simakova, V.N. Parmon, M.A. Samorukova*, V.P. Boyarskii**, T.E. Zhesko**, V.I. Saloutin*, Yu.G. Yaltuk* (*Postovsky Institute of Organic Synthesis Yekaterinburg, Russia; **St.-Petersburg State University, St. Petersburg, Russia)

Chem. Sustain. Devel., 19(2) (2011) pp. 179-186.

Liquid-phase catalytic reductive dechlorination of toxic technogenic products using catalysts M/Sibunit (M = Ni, Pt, Pd) was investigated. It was shown that the highest activity is exhibited by catalysts based on palladium.

ADSORPTION-CATALYTIC NEUTRALIZATION OF EXHAUST GASES OF DIESEL ENGINES

I.V. Mishakov, A.A. Vedyagin, A.M. Volodin, M.S. Myakisheva

Chem. Sustain. Devel., 19(1) (2011) pp. 97-104.

The basic aspects of environmental protection from hazardous gaseous impurities present in the exhaust gases of diesel engines are considered. Approaches used for the development of fundamental investigation of adsorbents and catalysts for afterburning СО and hydrocarbons are outlined. Results of the investigation of adsorption capacity of zeolites BEA- and Y-types with respect to heavy hydrocarbons (decane and toluene) obtained with the help of the gravimetric microanalyzer TEOM are presented. It is shown that both zeolites possess comparable capacities with respect to toluene, while the presence of mesopores in BEA-zeolite determines its substantially larger adsorption capcsity with respect to decane. For Pd/Al2O3 catalysts as example, the effect of the nature of precursor of active component and treatment conditions on the activity of the catalysts in the oxidation of CO is considered. It is demonstrated that in the case of the mass fraction of deposited chloride components up to 0.25-0.5 % atomically dispersed forms of palladium are formed; they are responsible for the high activity of palladium catalysts

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