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Mechanistic study of 1,1-dimethylhydrazine transformation over Pt/SiO₂ catalyst.

ABSTRACT: Catalytic oxidation of 1,1-dimethylhydrazine (UDMH) with molecular oxygen over Pt/SiO₂ was studied by in situ FTIR spectroscopy coupled with online MS monitoring of the gas phase. An unusual two-step oxidation process was detected in experiments with the pulse UDMH feeding: initial UDMH oxidation over a fresh platinum surface quickly terminates due to the blockage of active sites; a time-separated second oxidation step corresponds to combustion of the surface residue. This residue consists of C[triple bond, length as m-dash]N nitrile groups formed via decomposition of the products of non-oxidative UDMH conversion, such as dimethylamine. The two-step oxidation picture is observed over a broad range of reaction temperatures and oxygen to UDMH ratios.

SUBMITTER: Smirnov AV

PROVIDER: S-EPMC9089307 | biostudies-literature | 2018 Oct

REPOSITORIES: biostudies-literature

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Mechanistic study of 1,1-dimethylhydrazine transformation over Pt/SiO2 catalyst.

Smirnov Andrei V AV Smirnov Andrei V AV Kots Pavel A PA Panteleyev Maksim A MA Ivanova Irina I II

RSC advances 20181001 64

Catalytic oxidation of 1,1-dimethylhydrazine (UDMH) with molecular oxygen over Pt/SiO2 was studied by in situ FTIR spectroscopy coupled with online MS monitoring of the gas phase. An unusual two-step oxidation process was detected in experiments with the pulse UDMH feeding: initial UDMH oxidation over a fresh platinum surface quickly terminates due to the blockage of active sites; a time-separated second oxidation step corresponds to combustion of the surface residue. This resi ...[more]

PMID: 35558958

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