2020 Fiscal Year Annual Research Report
実験と理論の協働によるメタン多量化反応の機構解明と触媒設計
| Project/Area Number |
19F19059
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| Research Institution | Hokkaido University |
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Principal Investigator |
清水 研一 北海道大学, 触媒科学研究所, 教授 (60324000)
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| Co-Investigator(Kenkyū-buntansha) |
LIU CHONG 北海道大学, 触媒科学研究所, 外国人特別研究員
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| Project Period (FY) |
2019-04-25 – 2021-03-31
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| Keywords | NH3-SCR / O2 activation / zeolites |
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| Outline of Annual Research Achievements |
Selective catalytic reduction of nitrogen oxides using ammonia (NH3-SCR) over Cu-exchanged zeolites is an important process and proceeds via reduction of Cu(II) to Cu(I) and subsequent reoxidation of Cu(I) to Cu(II). Although the mechanism of reduction half cycle has been relatively well established, reoxidation pathways of Cu(I) to form the original Cu(II) species are highly complicated and remain unclear. In our study, oxidation mechanisms of Cu(I) to Cu(II) species in CHA zeolites during the NH3-SCR process were investigated by periodic DFT calculations. The NH3-solvated Cu(I) and Cu(II) species were considered for exploring the oxidative activation reaction pathways. The results show that, with O2 as the sole oxidant, Cu(I) can be effectively oxidized to Cu(II) via multinuclear Cu-oxo intermediates with moderate reaction barriers. The NO-assisted oxidation of Cu(I) was found to favor the formation of Cu nitrate/nitrite species, which seem to only act as off-cycle resting states. We propose that reoxidation of Cu(I) to Cu(II) with O2 as the sole oxidant plays a key role in the oxidation half cycle under standard NH3-SCR conditions. The obtained information would be important for various catalytic processes over cation-exchanged zeolites.
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| Research Progress Status |
令和2年度が最終年度であるため、記入しない。
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| Strategy for Future Research Activity |
令和2年度が最終年度であるため、記入しない。
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Research Products
(3 results)
