Kinetics of the Reaction of Methyl Radical with Methanol

Abstract

This work studied theoretically in details the mechanism, kinetics and thermochemistry of reactions of methyl radical with methanol. The theoretical study was carried out by ab initio molecular orbital theory based on CCSD(T)/B3LYP/6-311++G(3df,2p) methods in conjunction variational transition state theory (VTST). Calculated results showed that, in the temperature range from 300K to 2000K, and the pressure at 760 Torr, temperature dependent rate constants of the reactions were:

CH₃ + CH₃OH ® CH₄ + CH₂OH    k(T) = 2.146´10^-27.T^4.64.exp(-33.47[kJ/mol/RT),

CH₃ + CH₃OH ® CH₄ + CH₃O       k(T) = 2.583´10^-27.T^4.52.exp(-29.56[kJ/mol/RT),

CH₃ + CH₃OH ® H + CH₃OCH₃    k(T) = 1.025´10^-23.T^3.16.exp(-186.84[kJ/mol/RT)

When the reaction temperature is above 730 K, the abstraction process of H in –CH₃ group of methanol will occur faster. The abstraction process of H in –OH group dominates when the reaction temperature is below 730 K.

Keywords

Kinetic, methyl, methanol, ab initio

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