Decomposition of ethane

The reaction between hydrogen and chlorine is probably also of this type and many organic free radical reactions (e.g. the decomposition of ethanal) proceed via chain mechanisms. 

Burcat A, Skinner G B, Crossley R W and Scheller K 1973 High temperature decomposition of ethane Int. J. Chem. Kinetics 5 345-52... 

H. Bockborn and co-workers, "Production of Acetylene ia Premixed Flames and of Acetylene—Ethylene Mixtures," Chem. Ing. Pechnol. 44(14), 869 (1972). "Thermal Decomposition of Ethane ia a Plasma Jet," Rogyo Kagaku Zasshil4(9), 83 (1971). 

The following mechanism has been postulated for the decomposition of ethane into ethylene and hydrogen. The overall rate expression is first order in ethane. 

The decomposition of ethane has been extensively studied and several mechanisms have been postulated. The main products of the reaction are ethylene, C2F14, and hydrogen, Hj. However, there are small amounts of methane, CH4, butane, and other products. 

Consider the gas-phase decomposition of ethane (A) to ethylene at 750°C and 101 kPa (assume both constant) in a PFR. If the reaction is first-order with kA = 0.534s-1(Fro-ment and Bischoff, 1990, p. 351), and r is 1 s, calculate /a- For comparison, repeat the calculation on the assumption that density is constant. (In both cases, assume the reaction is irreversible.)... 

M S. Zhurko, F.V. (2006a). Formation and decomposition of ethane, propane, and carbon dioxide hydrates in silica gel mesopores under high pressure. J. Phys. Chem. B, 110 (39), 19717-19725. 

Marcus and Rice6 made a more detailed analysis of the recombination from the point of view of the reverse reaction, the unimolecular decomposition of ethane, C2Ha - 2CH3. By the principle of microscopic reversibility the transition states must be the same for forward and reverse paths. Although they reached no definite conclusion they pointed out that a very efficient recombination of CH3 radicals would imply a very high Arrhenius A factor for the unimolecular rate constant of the C2H6 decomposition which in turn would be compatible only with a very "loose transition state. Conversely, a very low recombination efficiency would imply a very tight structure for the transition state and a low A factor for the unimolecular decomposition. 

Question. The gas phase decomposition of ethanal occurs according to CH3CHO(g) - CH4(g) + CO(g)... 

The Thermal decomposition of ethane to ethylene, methane, butane, and hydrogen can be expressed by the following mechanism. 

Hydrogen, metliane, and ethylene are also at tunes to be fomid amongst the products of oxidation, without, however, any carbon being liberated. Their appearance is believed to be due to the purely thermal decomposition of ethane, formaldehyde, and acetaldehyde.3 Thus ... 

In the steady-state approximation of the analysis of the kinetics of the reaction for the decomposition of ethane, the equation... 

The mercury-photosensitized decomposition of ethane has been studied by Bywater and Steacie , and by Back who worked at very low conversions in order to avoid back reactions. Back s results, otained at 240 °C, are consistent with the following simple mechanism... 

It is important to note that the power n in the rate expression has no direct relation to the coefficient a in the balanced chemical equation. This number has to be determined experimentally for each rate law. For the decomposition of ethane at high temperatures and low pressures,... 

For such a second-order reaction, a plot of Ijc against t is linear (Fig. 18.7). The factor 2 multiplying kt in this expression arises from the stoichiometric coefficient 2 for NO2 in the balanced equation for the specific example reaction. For other second-order reactions with different stoichiometric coefficients for the reactant (see the thermal decomposition of ethane described on page 755), we must modify the integrated rate law accordingly. 

There are many first-order reactions. An example is the decomposition of ethane (C2Hg) into highly reactive fragments called methyl radicals (CH3) ... 

The decomposition of ethane (C2H6) to methyl radicals is a first-order reaction with a rate constant of 5.36 X 10 " s at 700°C ... 

Carbon Formation from Catalyzed Decomposition of Ethane at 700 C... 

In the present macro-scale experiments the filaments have been formed following reaction of ethane with iron and iron oxides. The decomposition of ethane to elemental carbon and hydrogen is endothermic (27) and so, at first sight, it appears that the experimental results are in conflict with the above mechanism of filament growth. However, earlier work (28) has shown that the majority of carbon formed from ethane arises from the decomposition product ethylene. The latter decomposes exothermically (27) (- A H for C2H4 at 725°C is 9.2 kcal. mole- ) so that this mechanism is not contravened. A similar rationale was used by Keep, Baker and France (29) to account for the formation of carbon filaments during the nickel catalyzed decomposition of propane. 

A typical organic free-radical chain reaction is the decomposition of ethane,... 

K. J. Laidler and B. W. Wojclechowski. Kinetics and mechanisms of the thermal decomposition of ethane. 1. The uninhibited reaction. Proceedings of the Royal Society of London, Math and Physics, 260A(1300) 91-102, 1961. 

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