High-temperature pyrolysis of toluene

Abstract

As shown in Figure 5, our present plot is rather similar to that of Baulch et al.15 Lin and Bauer6 obtained k6 = 2.8 X 1012 exp(99.6 kJ) cm6• moL1 2-s_1. In order to explain the negative activation energy, they proposed the following mechanism for the reaction: 0(3P) + CO('Here, C02*(3B2) and C02*('Sg+) represent vibrationally excited C02 in the 3B2 and '2g+ states, respectively. Further, they assumed that the rate-determining step is a transition between the 3B2 state and the * 8+ state and calculated that the crossing point between the 3B2 and * 8+ states is 31.4 kJ/mol below the 3B2 dissociation limit. On the other hand, Clyne and Thrush19 studied the reaction 0(3P) + )(' +) -* C02(%+) + hv (18) Warnatz,

Experimental and modeling study of the oxidation of toluene

“…CO elimination (56-58) would lead to the formation of ·C 5 H 4 CH 3 radicals, but Emdee et al [2] proposed a fast rearrangement of this species to give ·H atoms and benzene (56). We propose here that betascissions from this radical can also lead to the opening of the ring and to the formation of small linear unsaturated species (57,58).…”

“…Like phenoxy radicals [11], cresoxy radicals can react by CO elimination (56)(57)(58) or combine with Hatoms (59). CO elimination (56-58) would lead to the formation of ·C 5 H 4 CH 3 radicals, but Emdee et al [2] proposed a fast rearrangement of this species to give ·H atoms and benzene (56).…”

“…Cresoxy radicals can also react by CO elimination to give benzene and H· atoms (56), acetylene, vinylacetylene, and H· atoms (57) or allene and propargyl radicals (58). The importance of these reactions, which are responsible for most of the formation of acetylene and allene at 893 K, increases with temperature.…”

DFT Study of Mechanism and Kinetics of Hydrogenolysis of Toluene

“…Even though their model is in good agreement with experimental data for their desired temperature range (for the xylene and toluene system), it was based on the assumption that the methyl radical addition reaction has the same barrier ashydrogen radical addition. Other researchers have performed more extensive studies that suggest different mechanisms for pyrolysis of toluene [2][3][4][5][6][7]. Most of the experimental work on toluene pyrolysis has been limited to specific operating conditions.…”

“…For methylphenyl formation, the reaction of toluene with hydrogen or methyl radical Our calculated rates show very good agreement with the experimental rates reported at the temperature range between 700-1300 which is well suited for simulation of carbon nanotubes production using Computational Fluid Dynamics. Table 4: Comparison of experimental reaction rate constants [3] with the calculated rate constants at B3LYP-6-311(d,p)…”