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[EN] In the presented studies an influence of different parameters, such as zeolite sample porosity, form of used iron source ([Fe-3(OAc)(6)O(H2O)(3)](+)oligocations or FeSO4 solutions) and method of iron species deposition (ion-exchange, impregnation), on the catalytic activity in the process of the selective catalytic oxidation of ammonia (NH3-SCO) was studied. Conventional and mesoporous ZSM-5 zeolites, obtained by desilication and modified with iron species, were analysed with respect to their textural, surface and crystalline properties (N-2-sorption, HRTEM, SEM, XRD) as well as the form of introduced Fe species (UV-vis-DRS). Ion-exchange with [Fe-3(OAc)(6)O (H2O)(3)](+) oligocations and impregnation with these oligocations and FeSO4 solutions were found as the most effective methods of the zeolite samples activation for NH3-SCO. ; This work was carried out in the frame of project No. 0670/IP3/2016/74 from the Polish Ministry of Science and Higher Education in the years 2016-2019. Part of the work was performed in the frame of project No. 2012/05/B/ST5/00269from the National Science Centre (Poland). U. D. acknowledges to the Spanish Government by the funding (MAT2017-82288-C2-1-P). The authors would like to acknowledge to Clariant Company for the providing of the HMFI zeolite material for the presented research. ; Borcuch, A.; Rutkowska, M.; Marzec, A.; Kowalczyk, A.; Michalik, M.; Moreno, J.; Díaz Morales, UM. (2020). Selective ammonia oxidation over ZSM-5 zeolite: Impact of catalyst's support porosity and type of deposited iron species. Catalysis Today. 348:223-229. https://doi.org/10.1016/j.cattod.2019.08.054 ; S ; 223 ; 229 ; 348 ; Weckhuysen, B. M., & Yu, J. (2015). Recent advances in zeolite chemistry and catalysis. Chemical Society Reviews, 44(20), 7022-7024. doi:10.1039/c5cs90100f ; Verboekend, D., & Pérez-Ramírez, J. (2011). Design of hierarchical zeolite catalysts by desilication. Catalysis Science & Technology, 1(6), 879. doi:10.1039/c1cy00150g ; Rutkowska, M., Pacia, I., Basąg, S., ...

[EN] In the present study, an influence of the iron aggregation in conventional and micro-mesoporous MFI on their catalytic activity in the NO reduction with ammonia (DeNO(x) process) was studied. Modification of MFI zeolite properties was done by the desilication in the presence of NaOH and TPAOH (tertapropylammonium hydroxide). In the next step, the samples were modified with iron by ion-exchange with the use of a conventional solution of Fe cations (FeSO4) and a solution of iron triple-metallic aggregates (oligocations) ([Fe-3(OAc)(6)O(H2O)(3)](+)). Both of the applied modification techniques (desilication and modification with Fe-3 oligocations) increased the catalytic activity of the MFI zeolite in the DeNO(x) process. This increased catalytic activity was connected with changes in sample porosity, Si/Al ratio, topology, as well as aggregation and dispersion of iron species on the catalyst surface, which was investigated by N-2-sorption, XRD, ICP, NMR, HRTEM and UV-vis-DRS techniques. ; This work was carried out in the frame of project No. 0670/IP3/2016/74 from the Polish Ministry of Science and Higher Education in the years 2016-2019 and in the frame of project No. 2012/05/B/ST5/00269 from the National Science Centre (Poland). U. D. acknowledges to the Spanish Government by the funding (MAT2017-82288-C2-1-P). ; Rutkowska, M.; Borcuch, A.; Marzec, A.; Kowalczyk, A.; Samojeden, B.; Moreno, J.; Díaz Morales, UM. (2020). Influence of iron aggregation on the catalytic performance of desilicated MFI in the DeNO(x) process. Microporous and Mesoporous Materials. 304:1-8. https://doi.org/10.1016/j.micromeso.2018.09.015 ; S ; 1 ; 8 ; 304

MCM-22, MCM-36, and ITQ-2 zeolites with the intended Si/Al molar ratios of 15, 25, and 50 were synthetized and tested as catalysts for dehydration of methanol to dimethyl ether and dehydration of ethanol to diethyl ether and ethylene. The surface concentration of acid sites was regulated by the synthesis of zeolite precursors with different aluminum content in the zeolite framework, while the influence of porous structure on the overall efficiency of alcohol conversion was analyzed by application of zeolitic materials with different types of porosity-microporous MCM-22 as well as microporous-mesoporous MCM-36 and ITQ-2. The zeolitic samples were characterized with respect to their: chemical composition (ICP-OES), structure (XRD, FT-IR), texture (N sorption), and surface acidity (NH-TPD). Comparison of the catalytic activity of the studied zeolitic catalysts with other reported catalytic systems, including zeolites with the similar Si/Al ratio as well as γ-AlO (one of the commercial catalysts for methanol dehydration), shows a great potential of MCM-22, MCM-36, and ITQ-2 in the reactions of alcohols dehydration. ; U.D. acknowledges to the Spanish Government grant number MAT2017-82288-C2-1-P. The research was partially done using the equipment purchased from the funds of European Regional Development Fund, Polish Innovation Economy Operational Program, grant numberPOIG.02.01.00-12-023/08.

[EN] In the presented study, H-Beta zeolite and H-Beta/meso (mesoporous Beta zeolite obtained by a mesotemplate-free method) were modified with Fe-3, Fe2Cr, FeCr2 and Cr-3 triple-metallic aggregates (oligocations) by ion-exchange method (for comparison modification with isolated Fe cations was also done). Successful synthesis of mesoporous Beta zeolite was confirmed by several techniques such as N-2-sorption, PXRD, AAS or NH3-TPD. Modified porosity and acidity of the Beta zeolite, as well as the source of metals used, influenced the form (coordination and aggregation), content and reducibility of Fe- and Cr-species in the samples (UV-vis-DRS, AAS, H-2-TPR). The obtained samples were tested as catalysts in the process of selective catalytic oxidation of ammonia to dinitrogen (NH3-SCO). The highest activity and selectivity for nitrogen was obtained for the bimetallic Fe-Cr samples prepared by deposition of suitable oligocations. ; This work was carried out in the frame of project No. 0670/IP3/2016/74 from the Polish Ministry of Science and Higher Education in the years 2016-2019 and in the frame of project No. 2012/05/B/ST5/00269 from the National Science Centre (Poland). U. D. acknowledges to the Spanish Government for funding (MAT2017-82288-C2-1-P). ; Rutkowska, M.; Duda, M.; Macina, D.; Górecka, S.; Debek, R.; Moreno-Rodríguez, JM.; Díaz Morales, UM. (2019). Mesoporous Beta zeolite functionalisation with FexCry oligocations; catalytic activity in the NH3-SCO process. Microporous and Mesoporous Materials. 278:1-13. https://doi.org/10.1016/j.micromeso.2018.11.003 ; S ; 1 ; 13 ; 278 ; Chmielarz, L., & Jabłońska, M. (2015). Advances in selective catalytic oxidation of ammonia to dinitrogen: a review. RSC Advances, 5(54), 43408-43431. doi:10.1039/c5ra03218k ; Jabłońska, M., & Palkovits, R. (2016). Copper based catalysts for the selective ammonia oxidation into nitrogen and water vapour—Recent trends and open challenges. Applied Catalysis B: Environmental, 181, 332-351. doi:10.1016/j.apcatb.2015.07.017 ; QI, ...