Modelling partial oxidation of methane over ZSM-5 and Mo6S8 catalysts
Other conference contribution, 2017

Partial oxidation of methane is an interesting but difficult reaction. Experimentally, methane can be partially oxidized to methanol over metal-exchanged zeolites. In particular the ZSM-5 zeolite has been widely studied and has been shown to be active when exchanged with Cu, Ni, Co, and Fe [1-4]. A clear [Cu-O-Cu] 2+ candidate for active site for the methane-to-methanol reaction has been put forth for Cu-ZSM-5 [1,5]. A first question to ask is whether this [Cu-O-Cu] 2+ motif is generic and could work also with Cu interchanged with Ni, Co, or Fe. Herein, we employ first-principles calculations and micro-kinetic modelling to compare the performance of Ni, Co, and Fe in this motif to the Cu one. Our finding is that the methane-to-methanol reaction can only realistically happen for Cu on this motif. Thus, this particular motif can be excluded as an active site candidate for Ni-, Co-, and Fe-ZSM-5 [6]. Another catalyst that is interesting for partial methane oxidation is the Mo6S8 cluster. However, instead of the methane-to-methanol reaction we use H2S as an oxidant and transform methane into hydrogen and CH3SH. Using electronic structure calculations and mean-field micro-kinetic modelling to study this reaction, we successfully capture the experimentally observed trend, i.e. that promoting the Mo 6 S 8 cluster with K increases the selectivity towards CH 3 SH, and Ni enhances the hydrogen formation [7].

[1] M. H. Groothaert, P. J. Smeets, B. F. Sels, P. A. Jacobs and R. A. Schoonheydt, J. Am. Chem. Soc., 127, 1394–1395 (2005).
[2] J. Shan, W. Huang, L. Nguyen, Y. Yu, S. Zhang, Y. Li, A. I. Frenkel and F. F. Tao, Langmuir, 30, 8558–8569 (2014).
[3] N. V. Beznis, B. M. Weckhuysen, and J. H. Bitter, Catal. Lett., 136, 52–56 (2010).
[4] E. V. Starokon, M. V. Parfenov, L. V. Pirutko, S. I. Abornev and G. I. Panov, J. Phys. Chem. C, 115, 2155–2161 (2011).
[5] J. S. Woertink, P. J. Smeets, M. H. Groothaert, M. A. Vance, B. F. Sels, R. A. Schoonheydt, and E. I. Solomon, Proc. Natl. Acad. Sci. U. S. A., 106, 18908–18913 (2009).
[6] A. A. Arvidsson, V. P. Zhdanov, P.-A. Carlsson, H. Grönbeck, and A. Hellman, Catal. Sci. Technol., 7, 1470, (2017).
[7] O. Y. Gutiérrez, L. Zhong, Y. Zhu, J. A. Lercher, ChemCatChem, 5, 3249–3259 (2013).

Zeolites

Micro-kinetic modelling

Cu-ZSM-5

DFT

Partial methane oxidation

Author

Adam Arvidsson

Chalmers, Physics, Chemical Physics

Anders Hellman

Chalmers, Physics, Chemical Physics

Swedish Theoretical Chemistry 2017 - Bridging gaps
Göteborg, Sweden,

Subject Categories

Inorganic Chemistry

Theoretical Chemistry

Organic Chemistry

More information

Latest update

6/3/2022 1