| Full text | |
| Author(s): |
Mizuno, Stefanie C. M.
[1]
;
Dulnee, Siriwan
[1]
;
Pereira, Tassia C. P.
[1]
;
Passini, Ricardo J.
[1]
;
Urquieta-Gonzalez, Ernesto A.
[1]
;
Gallo, Jean Marcel R.
[2]
;
Santos, Joao B. O.
[1]
;
Bueno, Jose M. C.
[1]
Total Authors: 8
|
| Affiliation: | [1] Univ Fed Sao Carlos, Dept Chem Engn, Rod Washington Luis, Km 235, CP 676, BR-13565905 Sao Carlos, SP - Brazil
[2] Univ Fed Sao Carlos, Dept Chem, Renewable Energy Nanotechnol & Catalysis Grp Gree, Rod Washington Luis, Km 235, CP 676, BR-13565905 Sao Carlos, SP - Brazil
Total Affiliations: 2
|
| Document type: | Journal article |
| Source: | CATALYSIS TODAY; v. 381, p. 13-25, DEC 1 2021. |
| Web of Science Citations: | 0 |
| Abstract | |
This work investigates the influences of Cu content, Si/Al ratio, and sample preparation method on the active Cu species in mordenite (MOR). The Cu/MOR prepared by multiple Cu-exchange procedures showed an optimum Cu/Al ratio for the formation of the most active species for methanol formation. XANES spectra indicated that isolated Cu+ species were formed after CH4 interaction and were re-oxidized under a flow of water steam. The Cu-MOR samples obtained by ion-exchange method presented well-dispersed CuO in the zeolite pores, while samples obtained by impregnation method presented segregated CuO and were inactive for CH4 activation. The methodology used for in situ UV-vis spectra analyses indicated that different Cu species were active for CH4 oxidation. Isolated Cu2+ species were not involved in CH4 activation at temperatures lower than 300 degrees C. The isolated Cu2+ species were partially hydrolyzed by O-2 treatment and species like {[}CuOH](+) and {[}CuOx](n) or polynuclear Cu2+-oxyhydroxide were formed. The formation of polynuclear species in substitution of di-copper would impact the specific activity with the Cu content and decrease the activity for methanol production. (AU) | |
| FAPESP's process: | 16/02128-2 - Design of new catalytic systems for the biorefinery |
| Grantee: | Jean Marcel Ribeiro Gallo |
| Support Opportunities: | Research Grants - Young Investigators Grants |
| FAPESP's process: | 18/26459-3 - Zeolites exchanged with CuxOy single sites for the methane partial oxidation to methanol: the effect of Zeolite structure and other metal oxides in the single site activity |
| Grantee: | Tássia Caroline Passos Pereira |
| Support Opportunities: | Scholarships in Brazil - Doctorate (Direct) |
| FAPESP's process: | 18/01258-5 - Novel chemical catalytic and photocatalytic processes for the direct conversion of methane and CO2 to products |
| Grantee: | José Maria Correa Bueno |
| Support Opportunities: | Research Projects - Thematic Grants |