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was found that Cu-mordenite materials with exceptionally high productivity had a significant concentration of framework-associated Cu2+ species that are resistant to self-reduction, establishing a clear correlation between these species and the MeOH productivity across a range of Cu-Mordenite zeolites. Current work once more took advantage of BM31 s capabilities and the XANES and extended X-ray absorption fine structure (EXAFS) region of the Cu k-edge were collected for the select samples of the MOR-Al2(SO4)3 and MOR-NaAlO2 series. Figure 135 shows that the most productive sample

(0.11CuHMOR-Al2(SO4)3) also has the most intense white line in the XANES region as well as the largest first shell contribution in the EXAFS part.

Based on previous work, this suggests a larger concentration of the highly active Cu2+ species, indicating that the location of Al in the framework plays an important part in generating the most active species for the oxidation of methane to methanol. Thus, for the first time, a clear synthesis-structure-activity relationship is established for Cu-mordenite.

Fig. 135: a) Reaction protocol for partial oxidation of CH4 and the MeOH productivity for the two mordenite (MOR) series. b) XANES spectra of the Cu K-edge for several activated Cu-mordenite

samples previously synthesised and tested for the partial oxidation of CH4. c) EXAFS region highlighting the first shell interactions.

PRINCIPAL PUBLICATION AND AUTHORS

Synthesis Structure Activity Relationship in Cu-MOR for Partial Methane Oxidation: Al Siting via Inorganic Structure-Directing Agents, S. Prodinger (a), K. Kvande (a), B. Arstad (b), E. Borfecchia (c), P. Beato (d), S. Svelle (a), ACS Catal. 12, 4, 2166-2177 (2022); https:/doi.org/10.1021/acscatal.1c05091 (a) Department of Chemistry, University of Oslo, (Norway) (b) SINTEF Industry (Norway) (c) Department of Chemistry, University of Turin (Italy) (d) Haldor Topsøe A/S, (Denmark)

REFERENCES

[1] D.K. Pappas et al., J. Am. Chem. Soc. 140, 15270 (2018).