ISSN print edition: 0366-6352
ISSN electronic edition: 1336-9075
Registr. No.: MK SR 9/7
Kinetics of Partial Methane Oxidation Process over the Fe-ZSM-5 Catalysts
Institute of Chemical and Environment Engineering, Szczecin University of Technology, PL-70 322 Szczecin
Abstract: Kinetics of a partial methane oxidation over the Fe-ZSM-5 catalysts was investigated. A set
of rate equations describing the reaction system was suggested and verified by comparison with
experimental data. It was found that all the reactions considered were of the zero order with
respect to oxygen and of the first order with respect to the oxidized species (methane, methanol, or
formaldehyde). Values of the reaction rate constant for the temperature range 350—550oC as well
as the reaction apparent activation energy values were determined.
The studies on the process of partial methane oxidation conducted over the Fe-ZSM-5 catalysts
confirmed the assumption that methanol and carbon dioxide are the primary products of the reaction.
As a result of the methanol oxidation, formaldehyde is generated, the oxidation of which leads
to receiving slight quantities of CO2.
The decline of the iron content results in the decrease of the rate of every reaction. In order to
impede the oxidation of methanol to formaldehyde, the H catalysts should be employed. This form is
responsible for the production of methanol; yet it also leads to the direct methane to carbon dioxide
oxidation. Bearing such dependences in mind, it could be concluded that the introduction of the
Fe-ZSM-5 catalyst demonstrating certain content might result in a favoured reaction of synthesis
of methanol, with the process of its further oxidation being hampered. Unfortunately, this makes
the elimination of the reaction of oxidation to CO2 virtually impossible.
It is also evident that the activation energy of methane to methanol or carbon dioxide oxidation
is markedly higher than the activation energy of the unwelcome reactions, which are methanol and
Full paper in Portable Document Format: 596aa403.pdf
Chemical Papers 59 (6a) 403–408 (2005)