Abstract
Alkali metals are commonly used to promote heterogeneous catalysts. For instance, K can enhance the MoS2-catalyzed synthesis of methanethiol, an important industrial chemical, from CO/H2/H2S. Herein, we not only demonstrate that the synergy increases with alkali cation size (Cs > Rb > K > Na) but also that alkali sulfides themselves are the active sites. The alkali-normalized methanethiol formation rate of Cs sulfide is nearly the same as that of Cs-promoted MoS2 with a much lower yield of unwanted methane. Kinetic measurements show that methanethiol on alkali sulfides is formed via the reaction 3 CO + 2 H2S → COS + CO2 + CH3SH. This represents a first example of H2S as a hydrogen donor for the formation of the thiol counterpart of methanol. The role of MoS2 is that of a promoter that disperses alkali and provides spillover H from H2 dissociation.
Original language | English |
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Pages (from-to) | 116-128 |
Number of pages | 13 |
Journal | Journal of Catalysis |
Volume | 405 |
DOIs | |
Publication status | Published - Jan 2022 |
Bibliographical note
Funding Information:Miao Yu acknowledges the financial support from the Chinese Scholarship Council. The authors thank Dr. Alessandro Longo from DUBBLE beamline (BM26A) at ESRF for assistance with XAS experiments.
Funding Information:
Miao Yu acknowledges the financial support from the Chinese Scholarship Council. The authors thank Dr. Alessandro Longo from DUBBLE beamline (BM26A) at ESRF for assistance with XAS experiments.
Funding
Miao Yu acknowledges the financial support from the Chinese Scholarship Council. The authors thank Dr. Alessandro Longo from DUBBLE beamline (BM26A) at ESRF for assistance with XAS experiments. Miao Yu acknowledges the financial support from the Chinese Scholarship Council. The authors thank Dr. Alessandro Longo from DUBBLE beamline (BM26A) at ESRF for assistance with XAS experiments.
Keywords
- Alkali metals
- Mechanism
- Methanethiol
- MoS
- Synergy