Position and Lewis acidic property of active cobalt species on MFI zeolite for catalytic methylation of benzene with methane
| Autor: | Kazu Okumura, Kana Yamamoto, Hitoshi Matsubara, Naonobu Katada, Satoshi Suganuma, Etsushi Tsuji, Koshiro Nakamura |
|---|---|
| Rok vydání: | 2021 |
| Předmět: |
chemistry.chemical_classification
chemistry.chemical_element 02 engineering and technology General Chemistry Methylation 010402 general chemistry 021001 nanoscience & nanotechnology Condensed Matter Physics 01 natural sciences Medicinal chemistry Methane 0104 chemical sciences Divalent Catalysis Ammonia chemistry.chemical_compound chemistry Mechanics of Materials General Materials Science 0210 nano-technology Benzene Zeolite Cobalt |
| Zdroj: | Microporous and Mesoporous Materials. 310:110649 |
| ISSN: | 1387-1811 |
| DOI: | 10.1016/j.micromeso.2020.110649 |
| Popis: | Crystallographic position and acidic properties of the Co species in MFI zeolite which was catalytically active for methylation of benzene with methane (CH4 + C6H6 → H3C–C6H5 + H2) were investigated with UV–vis spectroscopy and an ammonia IRMS-TPD method. Among the divalent cation sites in MFI classified into α, β and γ, loading of Co2+ at the α site on the wall of straight channel proceeded mainly in the relatively high Co concentration region (Cozeo/Alzeo > 0.25) without additive or in the low Co concentration region in the co-presence of Mg and Pb. On the other hand, Co2+ on MFI were classified from the view of Lewis acidity into four types (L1S, L1W, L2S and L2W). The L1S type possessing strong base-stabilizing and electron-withdrawing nature showed similar dependency on the Co content to the Co2+ at the α site as well as the catalytic activity for direct methylation of benzene with methane. These observations indicate that the Co2+ at the α site with L1S nature was active for the methylation of benzene with methane, a reaction promising to open a way of utilization of methane as a feedstock of valued chemicals. |
| Databáze: | OpenAIRE |
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