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A Proposal for the Mechanism of the CH + CO2 Reaction
Version 3 2019-10-18, 18:34
Version 2 2019-10-18, 15:03
Version 1 2019-10-17, 12:11
journal contribution
posted on 2019-10-18, 18:34 authored by Rafael M. Vichietti, Rene F. K. Spada, Albérico
B. F. da Silva, Francisco B. C. Machado, Roberto L. A. HaidukeFew experimental studies on the CH
+ CO2 global reaction propose H, CO, and HCO as major products.
However, the reaction mechanisms behind this process have not yet
been elucidated. Moreover, some intriguing kinetic particularities
were noticed in these previous investigations. The advanced theoretical
study performed here shows that a CH insertion mechanism is capable
of explaining all the experimental data available. Hence, the strong
deviations from a traditional Arrhenius behavior ascribed to the rate-determining
elementary reaction (the CH insertion step) account for the kinetic
particularities observed experimentally. A change in the preferred
product channel as temperatures increase (from HCO + CO to H + 2CO)
is also predicted to occur due to the HCO decomposition, although
the CH depletion rates in typical conditions are not affected by this
additional step.