Determination of rate equations of catalytic oxidation of propene to acrolein and acrylic acid in the gas phase

1986 ◽  
Vol 51 (8) ◽  
pp. 1579-1586
Author(s):  
Jiří Švachula ◽  
Antonín Tockstein ◽  
Josef Tichý
Keyword(s):  
Acrylic Acid ◽  
Catalytic Oxidation ◽  
Gas Phase ◽  
Oxide Catalyst ◽  
Rate Equations ◽  
Nickel Iron ◽  
Cobalt Nickel ◽  
Flow Circulation ◽  
Kinetics Of

The kinetics of propene catalytic oxidation to acrolein and acrylic acid was studied in a flow-circulation reactor over a multicomponent oxide catalyst containing molybdenum, cobalt, nickel, iron, bismuth, and potassium. The rate equations were found for the total formation of acrolein and acrylic acid.

Gas phase interaction with catalytic oxidation reactions

1972 ◽  
Vol 326 (1565) ◽  
pp. 215-227 ◽  
Keyword(s):  
Carbon Dioxide ◽  
Maleic Anhydride ◽  
Catalytic Oxidation ◽  
Gas Phase ◽  
Major Part ◽  
Oxidation Reactions ◽  
Mixed Gas ◽  
Kinetics Of ◽  
Oxidation Of Benzene ◽  
Homogeneous Decomposition

Studies of the catalytic oxidation of benzene to maleic anhydride and carbon dioxide over vanadia/molybdena catalysts show that the major part of the reaction involves interacting gas and gas-solid processes. The results are consistent with a mechanism in which a benzeneoxygen adduct is formed catalytically, desorbs and then reacts to give maleic anhydride entirely in the gas phase. On the basis of this proposed mechanism, the kinetics of individual reactions have been investigated in some depth. The over-oxidation of maleic anhydride has been found to be not significant under the conditions of reaction. The kinetic relationships governing the homogeneous decomposition of the adduct and the oxidation of the adduct to maleic anhydride and to carbon dioxide have been established. The results show that essentially all of the anhydride originates from mixed gas-solid/gas reaction while substantial amounts of carbon dioxide are produced entirely catalytically.

Determination of copper in catalysts with large excess of aluminum, cobalt, nickel, iron, and molybdenum

1977 ◽  
Vol 13 (7) ◽  
pp. 487-490
Author(s):  
N. P. Poezd ◽  
R. M. Andreeva ◽  
I. M. Kolesnikov ◽  
E. D. Radchenko ◽  
D. F. Poezd
Keyword(s):  
Large Excess ◽  
Nickel Iron ◽  
Cobalt Nickel ◽  
Determination Of Copper

Oxidation of acrolein to acrylic acid on vanadium molybdenum oxide catalyst; The reaction kinetics

1983 ◽  
Vol 48 (3) ◽  
pp. 698-702 ◽  
Author(s):  
Josef Tichý ◽  
Jiří Kůstka ◽  
Jaroslav Machek
Keyword(s):  
Acrylic Acid ◽  
Molybdenum Oxide ◽  
Atmospheric Pressure ◽  
Oxide Catalyst ◽  
Conversion Degree ◽  
Through Flow ◽  
Individual Reaction ◽  
Flow Apparatus ◽  
Kinetics Of ◽  
Integral Reactor

The oxidation kinetics of acrolein have been studied in gas phase in the presence of vanadium molybdenum oxide catalyst. Using a through-flow apparatus with integral reactor, the effect has been studied of concentration of individual reaction components, i.e. acrolein, oxygen, steam and acrylic acid, on conversion degree of acrolein. The measurements have been carried out at atmospheric pressure. For evaluation of the kinetic data measured an equation has been suggested expressing dependence of the oxidation rate on the mentioned parameters.

Kinetics of the gas phase reaction OH + NO(+M)→HONO(+M) and the determination of the UV absorption cross sections of HONO

1997 ◽  
Vol 272 (5-6) ◽  
pp. 383-390 ◽  
Author(s):  
Palle Pagsberg ◽  
Erling Bjergbakke ◽  
Emil Ratajczak ◽  
Alfred Sillesen
Keyword(s):  
Gas Phase ◽  
Cross Sections ◽  
Uv Absorption ◽  
Phase Reaction ◽  
Absorption Cross ◽  
Gas Phase Reaction ◽  
Kinetics Of

Kinetic Evaluation of Carbon Formation in Steam/CO2-Natural Gas Reformers. Influence of the Catalyst Activity and Alkalinity

2002 ◽  
Vol 1 (1) ◽  
Author(s):  
Joost-Willem Snoeck ◽  
Gilbert Froment ◽  
Martin Fowles
Keyword(s):  
Natural Gas ◽  
Gas Phase ◽  
Catalyst Activity ◽  
Accurate Determination ◽  
Activity Level ◽  
Carbon Formation ◽  
Kinetic Evaluation ◽  
Detailed Kinetics ◽  
Kinetics Of

The production of synthesis gas with a low H2/CO ratio from natural gas requires recycling the produced CO2, but this enhances the risk of carbon formation. A simulation model for steam/CO2 reformers comprising detailed kinetics of the main reactions but also of the carbon formation and gasification was used to evaluate the potential of carbon formation in the bulk gas phase and inside the catalyst particles along the reactor tube. Simulation results are presented for a number of cases with varying amounts of CO2 in the feed. The model permits an accurate determination of the minimum amount of steam or the maximum amount of CO2 that can be tolerated in the feed. Thermodynamic and kinetic criteria are compared, and a strategy for the evaluation of the risk of carbon formation is proposed. The importance of the activity level of the catalyst and of its alkalinity is also illustrated.

scholarly journals Kinetics of aldol condensation of acetic acid with formaldehyde on B–P–V–W–OX/SiO2 catalyst

2020 ◽  
Vol 3 (2) ◽  
pp. 39-45
Author(s):  
N. S. Pavliuk ◽  
◽  
V. V. Ivasiv ◽  
O. M. Orobchuk ◽  
D. S. Shevchenko ◽  
...  
Keyword(s):  
Acetic Acid ◽  
Chemical Composition ◽  
Acrylic Acid ◽  
Gas Phase ◽  
Silicon Oxide ◽  
Aldol Condensation ◽  
Condensation Reaction ◽  
Kinetic Equations ◽  
Stable Chemical ◽  
Kinetics Of

New catalysts B–P–V–W–Ox/SiO2 of gas-phase condensation of acetic acid from formaldehyde to acrylic acid on an industrial carrier of stable chemical composition (colloidal silicon oxide, Aerosil A-200) were synthesized. It is shown that the hydrothermal treatment of the carrier allows to increase the activity and selectivity of the catalyst in the reactions of aldol condensation of acetic acid with formaldehyde. It was found that the developed catalyst is effective in the condensation reaction of acetic acid with formaldehyde, which allows to obtain acrylic acid with a yield of 68.7% and a selectivity of 94.1%. The kinetic regularities of the reaction on this catalyst are established. According to the proposed kinetic equations, kinetic parameters are calculated that describe the condensation reaction of acetic acid with formaldehyde.

The kinetics of the catalytic oxidation over palladium of some alkanes and cycloalkanes

1976 ◽  
Vol 349 (1659) ◽  
pp. 523-534 ◽  
Keyword(s):  
Gas Phase ◽  
Surface Oxidation ◽  
Reaction Rates ◽  
Optimum Operating ◽  
Optimum Operating Temperature ◽  
Kinetics Of Oxidation ◽  
Low Concentrations ◽  
Diffusion Effects ◽  
Kinetics Of

Measurements have been made of the kinetics of oxidation over palladium of the C 1 to C 4 alkanes, cyclopropane and cyclohexane in the temperature range 588-873 K by means of a microcalorimetric bead technique. With an initially reduced and degassed catalyst, reaction rates for the alkanes increase from C 1 to C 4 , while butane, cyclopropane and cyclohexane are of comparable reactivity. The rates of oxidation of the alkanes are significantly increased when the catalyst is preheated in oxygen, and cyclo­propane oxidation is markedly enhanced by this procedure. Reactions are inhibited by gas-phase diffusion effects, particularly at higher tempera­tures; there is thus apparent inhibition by oxygen. All the reactions are preceded by the surface oxidation of the catalyst, this latter process having an activation energy of 176 ± 18 kJ mol -1 . Reaction appears to involve the interaction of hydrocarbon from the gas phase with palladium oxide, followed by the rapid desorption of carbon dioxide and the slower desorption of water. Large concentrations of water vapour cause a loss of catalytic activity, probably due to the formation of palladium hydroxide. When the bead system is used for the detection of low concentrations of hydrocarbons, the optimum operating temperature lies between 793 and 723 K, decreasing as the hydrocarbons become more reactive. The most significant single factor governing response is the heat of combustion, so that this method is most sensitive for the determination of high molecular mass hydrocarbons.

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