Étude expérimentale et modélisation théorique de la décomposition du radical éthyle

A bibliographical study of the thermal decomposition of the ethyl radical shows that the kinetic parameters for the upper and lower limits of the pressure are rather scattered. This observation explains why we have carried out a new study of this elementary process in the pyrolysis of ethane, around 800 K, in a closed vessel and at pressures of the hydrocarbon varying from 1 to 300 Torr. The experimental results have been treated according to three theoretical approaches: the RRKM theory and two methods proposed by Troe. In each case, an excellent fit of the theoretical curves with the experimental data is obtained, as well as Arrhenius expressions for the reaction rate constants at high and low pressures. A detailed critical analysis of our results as well as those found in the literature shows that as yet there is no good agreement between recent studies on this subject. However, it is possible to present two Arrhenius expressions for the reaction rate constants at high and low pressures; these expressions represent a good compromise for the results obtained by various authors:[Formula: see text][Journal translation]

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A Simple Method for Determining the Reaction Rate Constants of Monomolecular Reaction Systems from Experimental Data

Industrial & Engineering Chemistry Process Design and Development ◽

10.1021/i260061a009 ◽

1977 ◽

Vol 16 (1) ◽

pp. 59-63 ◽

Cited By ~ 1

Author(s):

Feg-Wen Chang ◽

Thomas J. Fitzgerald ◽

Jin Yong Park

Keyword(s):

Experimental Data ◽

Rate Constants ◽

Reaction Rate ◽

Simple Method ◽

Reaction Systems ◽

Reaction Rate Constants ◽

Monomolecular Reaction

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Simulation of Crosslink and Graft Mechanism of Hydrogenated-NBR/ZINC Di-Methacrylate Composites by Moving Die Rheometer

Rubber Chemistry and Technology ◽

10.5254/1.3547694 ◽

2002 ◽

Vol 75 (5) ◽

pp. 943-954 ◽

Cited By ~ 6

Author(s):

Takashi Sato ◽

Akio Fujino ◽

Sachio Hayashi ◽

Motofumi Oyama ◽

Katsumichi Ono

Keyword(s):

Experimental Data ◽

Genetic Algorithm ◽

Rate Constants ◽

Reaction Rate ◽

Addition Reaction ◽

Algorithm Optimization ◽

Reaction Rate Constants ◽

Data Comparison ◽

Graft Reaction ◽

Comparison With Experimental Data

Abstract This paper studies the crosslink and graft mechanism of hydrogenated-NBR/zinc di-methacrylate (HNBR/ZDMA) composites. The experiments to determine the rate constants of crosslink and graft reaction formulas are from Moving Die Rheometer (MDR) data. Comparison with experimental data and the solution of simultaneous ordinary differential equations for the crosslink and graft reactions are performed. Genetic algorithm optimization of the reaction rate constants allowed for simulation of crosslinking and graft reaction process. This simulation predicts that the HNBR/peroxide cure system will contain 0.1052-mole/l crosslink between matrix HNBR polymer at 2 phr.-peroxide concentration. The crosslink concentration of 0.1052-mole/l is composed of 0.0308-mole/l-addition reaction and 0.0744-mole/l-termination reaction. Moreover, the HNBR/ZDMA cure system contains 0.0148-mole/l graft of poly-ZDMA to HNBR and 0.0903-mole/l crosslink between matrix HNBR polymer at a 2 phr.-peroxide concentration.

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Aromatization of light naphtha fractions on zeolites 1: Kinetic model

Hemijska industrija ◽

10.2298/hemind0309399r ◽

2003 ◽

Vol 57 (9) ◽

pp. 399-403 ◽

Cited By ~ 4

Author(s):

Svetlana Rovenskaja ◽

Nikolaj Ostrovski

Keyword(s):

Experimental Data ◽

Kinetic Model ◽

Rate Constants ◽

Reaction Rate ◽

Reaction Scheme ◽

Activation Energies ◽

Modeling And Optimization ◽

Light Naphtha ◽

Reaction Rate Constants

On the basis of analyzing kinetic experimental data performed in laboratory integral reactors a lumping kinetic model of the "Zeoforming" process was developed. A reaction scheme of the lumped components was proposed, that was adapted to the technological requirements. The reaction rate constants and activation energies were estimated, that are valid for certain feed compositions. The model is intended for further modeling and optimization of the process.

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Flame Stabilisation in High Velocity Gas Streams and the Effect of Heat Losses at Low Pressures

Aeronautical Quarterly ◽

10.1017/s0001925900001190 ◽

1954 ◽

Vol 5 (4) ◽

pp. 195-217 ◽

Cited By ~ 15

Author(s):

D. B. Spalding ◽

B. S. Tall

Keyword(s):

Experimental Data ◽

High Velocity ◽

Combustible Mixture ◽

Heat Losses ◽

Gas Streams ◽

Theoretical Approaches ◽

Theoretical Predictions ◽

Flame Region ◽

Low Pressures ◽

Good Agreement

SummaryThe first object of this paper is to show the concordance between three different theoretical approaches to flame stabilisation and to compare published experimental data with the theoretical predictions. Good agreement between the theory and experimental results is obtained. The second object is to show that, at low pressures, the predictions of these theories must be qualified in view of the increasing importance of heat losses from the flame region. It is shown that there must exist a minimum pressure below which a flame cannot be maintained in a given combustible mixture, irrespective of the rate of flow of the mixture, unless heat losses are entirely eliminated.

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