Kinetics propylene activation energy

Hydrocarbon conversions can. In general, be represented fairly well by first-order reaction kinetics, and the conversion levels for runs made with a constant hydrocarbon flow rate as a general rule Increased significantly as the temperature Increased. Figures 1, 2, and 3 show typical results for ethane, propane, ethylene, and propylene. Based on first-order kinetics, the activation energies for ethane, propane, ethylene, and propylene were determined In the various reactors tested. In the Vycor reactor, these activation energies were approximately 51, 57, 56, and 66 k cal/g mole respectively. They were much lower In metal reactors especially after the reactor was oxidized. In a relatively new and unoxidized Incoloy reactor, the activation energies were 15, 47, 27, and 26 k cal/g mole respectively. 

If the zero-order method of section 2.6 reveals to be efficient, then it should be used to compare fast and slow oxidizing hydrocarbons (alkenes and methane for example). It is expected that the activation energy is constant in a homologous series of hydrocarbons. Then, the ratio of the rates of reaction should Be close to the ratio of the zero-order kinetic constants determined with the LO ciuves. This fortunate situation would enable one to scale the rates of oxidation of various hydrocarbons with respect to a standard hydrocarbon (propylene for example). 

In the present work, propane-propylene mixtures with various ratios were pyrolyzed at temperatures near 900°C and at an atmospheric pressure in an annular flow reactor. Hydrogen was used as a diluent. Under these experimental conditions, it was rather difficult to maintain an uniform temperature throughout the reactor since the reaction rate was high, and consequently, thermal effects due to the heat reaction were significant. In this work, therefore, experimental data at the initial stage of decomposition were analyzed using the effective temperature method to obtain kinetic rate parameters, activation energy and frequency factor, for propane and propylene decompositions. From the relations between... 

Schmidt and coworkers [551] have reported the effect of organoaluminum compounds on the catalytic properties of complex catalysts used in the oligomerization of propylene. The selectivity for the process depends strongly on temperature, pressure, and contact time. In a continuous process of oligomerization of propylene at 200 atm with AlEts activation it is observed that the yield of oligomers increases with temperature [552]. Studies on the oligomerization kinetics [553,5541 have shown that the reaction order with respect to propylene is close to unity. Activation energies of 11.7 and 14 kcal mol have been reported [553,554]. 

With the [(7r-Cy)NiCll2-TiCl4 catalyst system the activation energy for the dimerization of propylene is observed to be 15.2 kcal/mol [591], The kinetics and product distribution for this and several other (TT-alkyDnickel catalysts have been determined with PPh3 as proton acceptors the yield of 2-methyl-2-pentene varies from 13 to 56.5%. 

The composition of these elastomers plays an important role in the degradation kinetics. The relative ration of ethylene content to propylene loading influences the progress in the oxidation process by the involvement of various values of activation energy (Fig. 19). It was reported [85] the higher content of ethylene increases the thermal stability of EPDM. 

The kinetic constants of olefin formation at 350°C follow the order kC > kC > C2 activation energy for propylene formation is lower than it is for other olefins [133]. 

In step (ii), the activation energy for the dehydrogenation of 1-propyl and 2-propyl are calculated to be 0.70 and 0.68 eV on Pt(lll) (Yang et al., 2011), respectively. Likewise, the configurations of the transition states resemble the adsorption configuration of propylene. Both the two reactions take place at the Bridge site, and the comparable activation energies indicate that both of the two reaction pathways are kinetically probable. 

Ozone rate constants, 27 771 Ozone reactions activation of, 27 779 kinetics and mechanism of, 27 778-779 Ozone resistance, of ethylene-propylene polymers, 10 704, 717 Ozone synthesis, energy requirements for, 27 798... 

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