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Investigation of Reaction Mechanism of NO-C₃H₆-CO-O₂ Reaction over NiFe₂O₄ Catalyst.

ABSTRACT: To elucidate the reaction mechanism of NO-C₃H₆-CO-O₂ over NiFe₂O₄, we investigated the dynamics of the adsorbed and gaseous species during the reaction using operando Fourier transform infrared (FTIR). The NO reduction activity dependent on the C₃H₆ and CO concentrations suggested that NO is reduced by C₃H₆ under three-way catalytic conditions. From FTIR measurements and kinetic analysis, it was clarified that the acetate species reacted with NO-O₂ to form N₂ via NCO, and that the rate-limiting step of NO reduction was the reaction between CH₃COO^- and NO-O₂. The NO reduction mechanism of the three-way catalyst on NiFe₂O₄ is different to that on platinum-group metal catalysts, on which NO reduction proceeds through N-O cleavage.

SUBMITTER: Ueda K

PROVIDER: S-EPMC6641588 | biostudies-literature | 2017 Jul

REPOSITORIES: biostudies-literature

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Investigation of Reaction Mechanism of NO-C3H6-CO-O2 Reaction over NiFe2O4 Catalyst.

Ueda Kakuya K Ohyama Junya J Satsuma Atsushi A

ACS omega 20170705 7

To elucidate the reaction mechanism of NO-C3H6-CO-O2 over NiFe2O4, we investigated the dynamics of the adsorbed and gaseous species during the reaction using operando Fourier transform infrared (FTIR). The NO reduction activity dependent on the C3H6 and CO concentrations suggested that NO is reduced by C3H6 under three-way catalytic conditions. From FTIR measurements and kinetic analysis, it was cl ...[more]

PMID: 31457643

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