2019 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 | dehydrogenation / ethane / zeolites / DFT |
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| Outline of Annual Research Achievements |
Non-oxidative dehydrogenation of C2H6 is an attractive chemical process to obtain C2H4 as an essential raw material for the chemical industry accompanied with H2 production. Our group found that the In-exchanged CHA zeolite (In-CHA) catalyzed the dehydrogenation of C2H6 in high selective manner without co-feeding gas. In-CHA maintained its activity and selectivity for at least 90 h. The active In species and the reaction mechanism were also investigated based on spectroscopic and theoretical studies. DFT calculations were performed by the Vienna ab-initio simulation package (VASP) with the periodic boundary condition.The FT-IR spectrum after C2H6 treatment exhibited the band with maxima at 1720 cm-1 derived from of In－H vibrations. The frequency calculation of several In-hydride models revealed that In－H vibrations of [InH2]+ ions are in good agreement with the results of FT-IR measurements. The TS calculation of C2H6 dehydrogenation via concerted mechanism on [InH2]+ ions shows that the activation barrier (Ea) for C－H cleavage of C2H6 is estimated to be 237.5 kJ/mol. This value is similar to Ea based on kinetic studies (244 kJ/mol) and is much lower than that in the TS calculation of dehydrogenation on In+ cations (430.8 kJ/mol). From the result of FT-IR measurement and TS calculations, [InH2]+ ions are likely to be catalytically active sites rather than In+ cations for the C2H6 dehydrogenation using In-CHA.
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| Current Status of Research Progress |
Current Status of Research Progress
2: Research has progressed on the whole more than it was originally planned.
Reason
Experimental and computational data are consistent with each other.
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| Strategy for Future Research Activity |
This year, I will find In-exchanged CHA zeolite (In-CHA) catalyzed dehydrogenation of methane. The active In species and the reaction mechanism will be investigated based on spectroscopic and theoretical studies.
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