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Zeolites with MWW topology (MCM-22, ITQ-2, and MCM-36) exchanged with copper and iron were studied as catalysts for selective catalytic reduction of NO with ammonia. It was shown that delamination and pillaring of layered MCM-22 zeolite resulted in the formation of ITQ-2 and MCM-36, respectively. Both these materials were characterized by MWW topology and significant contribution of mesopores. In a series of the zeolite based catalyst the most promising results in a process of selective catalytic reduction of NO with ammonia were obtained for the copper doped samples (Cu-MCM-22 and Cu-ITQ-2), however catalytic performance of the studied catalytic systems strongly depends on type, content and form of deposited transition metal species. Moreover, both these catalysts were found to be catalytically stable in the DeNOx process after hydrothermal treatment. ; U.D. and A.E.P. thank for the financial support to Spanish Government by Consolider-Ingenio MULTICAT CSD2009-00050, MAT2011-29020-0O2-01 and Severo Ochoa Excellence Program SEV-2012-0267. ; Rutkowska, M.; Díaz Morales, UM.; Palomares Gimeno, AE.; Chmielarz, L. (2015). Cu and Fe modified derivatives of 2D MWW-type zeolites (MCM-22, ITQ-2 and MCM-36) as new catalysts for DeNOx process. Applied Catalysis B: Environmental. 168:531-539. https://doi.org/10.1016/j.apcatb.2015.01.016 ; S ; 531 ; 539 ; 168

In the presented studies, a new method for the synthesis of hierarchical porous materials with ZSM-5 zeolite properties was applied. The proposed method is based on the acidification of the zeolite seeds slurry using HCl solution, followed by hydrothermal treatment, enabling the aggregation of zeolite nanoseeds with the formation of the interparticle mesoporous structure. The influence of the duration of zeolite parent mixture aging before and after acidification on the resulting properties of the samples was investigated. The physicochemical properties of the obtained micro-mesoporous samples were analyzed using techniques such as N-2-sorption measurements, X-ray diffraction, TG analysis, NH3-TPD and electron microscopy. In the second part of the studies, the influence of the modified zeolite sample parameters (such as porosity, acidity and crystallinity) on their catalytic activity for dimethyl ether (DME) synthesis from methanol was studied. DME is considered as a future clean alternative to diesel fuel and the development of methods for its synthesis is currently of high scientific interest. It was shown that modification of the porous structure and acidity of the zeolitic samples strongly influences their catalytic activity, selectivity and stability for the DME synthesis process. The micro-mesoporous samples, despite their significantly lower acidity, exhibited high catalytic activity (similar to conventional ZSM-5 zeolite) and enhanced selectivity towards DME, as well as higher stability in a long term catalytic test (higher resistance to the formation of coke deposits) in comparison to standard MFI-type zeolites. ; This work was supported by the National Science Center under grant no. 2011/03/N/ST5/04820. Part of the research was carried out with equipment purchased thanks to the financial support of the European Regional Development Fund in the framework of the Polish Innovation Economy Operational Program (contract no. POIG.02.01.00-12-023/08). U. D. gives thanks to Spanish Government by the funding ...

Titanium-silicon ferrierites with different Si/Ti ratios and their delaminated forms were modified with copper by ion-exchange. The obtained samples were characterized with respect to their chemical composition (ICP-OES), structure (XRD), texture (Nsorption), morphology (SEM), form and aggregation of titanium and copper species (UV-vis-DRS), reducibility of deposited copper species (H-TPR) and surface acidity (NH-TPD). The porous structure of the zeolitic samples strongly influenced the form and aggregation of deposited copper species. In the case of the three dimensional microporous structure of ferrierites (Ti-FER), copper was deposited mainly in the form of aggregated copper oxide species, in contrast to the open micro- and mesoporous structure of delaminated ferrierites (Ti-ITQ-6), where mainly copper in the form of monomeric cations was identified. It was shown that monomeric copper cations are more catalytically active in NO to NOoxidation than aggregated copper oxide species and, therefore, for the low-temperature conversion of nitrogen oxides the fast SCR reaction pathway is more effective for delaminated ferrierites modified with copper (Cu-Ti-ITQ-6) than for microporous three dimensional ferrierite catalysts (Cu-Ti-FER). ; The studies financed by National Science Centre – Poland [2016/21/B/ST5/00242]. A. Ś. has been partly supported by the EU Project POWR.03.02.00-00-I004/16. U. D. acknowledges to the Spanish Government by the funding [MAT2017-82288-C2-1-P]. Part of the research was done with equipment purchased in the frame of European Regional Development Fund (Polish Innovation Economy Operational Program [POIG.02.01.00-12-023/08]).

Ferrierites and their delaminated forms (ITQ-6), containing aluminum or titanium in the zeolite framework, were synthetized and modified with copper by an ion-exchange method. The obtained samples were characterized with respect to their chemical composition (ICP-OES), structure (XRD, UV-Vis DRS), textural parameters (N2-sorption), surface acidity (NH3-TPD), form and reducibility of deposited copper species (UV-Vis DRS and H2-TPR). Ferrierites and delaminated ITQ-6 zeolites modified with copper were studied as catalysts for the selective catalytic oxidation of ammonia to dinitrogen (NH3-SCO). It was shown that aggregated copper oxide species, which were preferentially formed on Ti-zeolites, were catalytically active in direct low-temperature ammonia oxidation to NO, while copper introduced into Al-zeolites was present mainly in the form of monomeric copper cations catalytically active in selective reduction of NO by ammonia to dinitrogen. It was postulated that ammonia oxidation in the presence of the studied catalysts proceeds according to the internal-selective catalytic reduction mechanism (i-SCR) and therefore the suitable ratio between aggregated copper oxide species and monomeric copper cations is necessary to obtain active and selective catalysts for the NH3-SCO process. Cu/Al-ITQ-6 presented the best catalytic properties possibly due to the most optimal ratio of these copper species. ; The studies financed by National Science Centre–Poland [2016/21/B/ST5/00242]. A.´S. has been partly supported by the EU Project POWR.03.02.00-00-I004/16. U.D. acknowledges the Spanish Government for the funding [MAT2017-82288-C2-1-P]. Part of the research was done with equipment purchased in the frame of European Regional Development Fund (Polish Innovation Economy Operational Program (POIG.02.01.00-12-023/08)).

The main goal of the study was the development of eective catalysts for the low-temperature selective catalytic reduction of NO with ammonia (NH3-SCR), based on ferrierite (FER) and its delaminated (ITQ-6) and silica-intercalated (ITQ-36) forms modified with copper. The copper exchange zeolitic samples, with the intended framework Si/Al ratio of 30 and 50, were synthetized and characterized with respect to their chemical composition (ICP-OES), structure (XRD), texture (low-temperature N2 adsorption), form and aggregation of deposited copper species (UV-vis-DRS), surface acidity (NH3-TPD) and reducibility (H2-TPR). The samples of the Cu-ITQ-6 and Cu-ITQ-36 series were found to be significantly more active NH3-SCR catalysts compared to Cu-FER. The activity of these catalysts in low-temperature NH3-SCR was assigned to the significant contribution of highly dispersed copper species (monomeric cations and small oligomeric species) catalytically active in the oxidation of NO to NO2, which is necessary for fast-SCR. The zeolitic catalysts, with the higher framework alumina content, were more eective in high-temperature NH3-SCR due to their limited catalytic activity in the side reaction of ammonia oxidation. ; The studies financed by National Science Centre–Poland [2016/21/B/ST5/00242]. A.´S. has been partly supported by the EU Project POWR.03.02.00-00-I004/16. U.D. acknowledges the Spanish Government for the funding [MAT2017-82288-C2-1-P]. Part of the research was done with equipment purchased in the frame of European Regional Development Fund (Polish Innovation Economy Operational Program (POIG.02.01.00-12-023/08)).

[EN] Ferrierites and their delaminated forms (ITQ-6), containing aluminum or titanium in the zeolite framework, were synthetized and modified with copper by an ion-exchange method. The obtained samples were characterized with respect to their chemical composition (ICP-OES), structure (XRD, UV-Vis DRS), textural parameters (N-2-sorption), surface acidity (NH3-TPD), form and reducibility of deposited copper species (UV-Vis DRS and H-2-TPR). Ferrierites and delaminated ITQ-6 zeolites modified with copper were studied as catalysts for the selective catalytic oxidation of ammonia to dinitrogen (NH3-SCO). It was shown that aggregated copper oxide species, which were preferentially formed on Ti-zeolites, were catalytically active in direct low-temperature ammonia oxidation to NO, while copper introduced into Al-zeolites was present mainly in the form of monomeric copper cations catalytically active in selective reduction of NO by ammonia to dinitrogen. It was postulated that ammonia oxidation in the presence of the studied catalysts proceeds according to the internal-selective catalytic reduction mechanism (i-SCR) and therefore the suitable ratio between aggregated copper oxide species and monomeric copper cations is necessary to obtain active and selective catalysts for the NH3-SCO process. Cu/Al-ITQ-6 presented the best catalytic properties possibly due to the most optimal ratio of these copper species. ; The studies financed by National Science Centre-Poland [2016/21/B/ST5/00242]. A. has been partly supported by the EU Project POWR.03.02.00-00-I004/16. U.D. acknowledges the Spanish Government for the funding [MAT2017-82288-C2-1-P]. Part of the research was done with equipment purchased in the frame of European Regional Development Fund (Polish Innovation Economy Operational Program (POIG.02.01.00-12-023/08)). ; Swies, A.; Rutkowska, M.; Kowalczyk, A.; Díaz Morales, UM.; Palomares Gimeno, AE.; Chmielarz, L. (2020). Ferrierite and Its Delaminated Forms Modified with Copper as Effective Catalysts for NH3-SCO Process. ...

[EN] 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-2 sorption), and surface acidity (NH3-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 gamma-Al2O3 (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. ; This research was funded by National Science Centre-Poland grant number 2016/21/B/ST5/00242. 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. ; Marosz, M.; Samojeden, B.; Kowalczyk, A.; Rutkowska, M.; Motak, M.; Díaz Morales, UM.; Palomares Gimeno, AE. (2020). MCM-22, MCM-36, and ITQ-2 Zeolites with Different Si/Al Molar Ratios as Effective Catalysts of Methanol and Ethanol Dehydration. Materials. 13(10):1-17. https://doi.org/10.3390/ma13102399 ; S ; 1 ; 17 ; 13 ; 10 ; Clausen, L. R., Houbak, N., & Elmegaard, B. (2010). Technoeconomic analysis of a methanol plant based on gasification of biomass and electrolysis of water. Energy, 35(5), 2338-2347. ...

1 17 13 10 ; S ; [EN] 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-2 sorption), and surface acidity (NH3-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 gamma-Al2O3 (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. This research was funded by National Science Centre-Poland grant number 2016/21/B/ST5/00242. 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. Marosz, M.; Samojeden, B.; Kowalczyk, A.; Rutkowska, M.; Motak, M.; Díaz Morales, UM.; Palomares Gimeno, AE. (2020). MCM-22, MCM-36, and ITQ-2 Zeolites with Different Si/Al Molar Ratios as Effective Catalysts of Methanol and Ethanol Dehydration. Materials. 13(10):1-17. https://doi.org/10.3390/ma13102399 Clausen, L. R., Houbak, N., & Elmegaard, B. (2010). Technoeconomic analysis of a methanol plant based on gasification of biomass and electrolysis of water. Energy, 35(5), 2338-2347. ...

Layered 2D zeolite MCM-22 and its delaminated derivative, ITQ-2, were modified with iron, by different methods (ion-exchange and direct synthesis), and with the use of different precursors (FeSO4.7H2O, Fe(NO3)3.9H2O, and [Fe3(OCOCH3)7.OH.2H2O]NO3 oligocations. The applied modifications were aimed at optimization of iron form in the samples (aggregation, amount, location, and reducibility), in order to achieve the highest catalytic activity in the N2O decomposition. The synthesis of the samples was verified with the use of XRD (X-Ray Diffraction), N2-sorption and ICP-OES (Inductively Coupled Plasma Optical Emission Spectroscopy) techniques, while the form of iron in the samples was investigated byUV¿vis-DRS (UV¿vis diffuse reflectance spectroscopy),H2-TPR (Hydrogen Temperature-Programmed Reduction) and HRTEM (High-Resolution Transmission Electron Microscopy). The highest activity in the N2O decomposition presented the sample Fe(O,IE)MCM-22, prepared by ion-exchange of MCM-22 with Fe3(III) oligocations. This activity was related to the oligomeric FexOy species (the main form of iron in the sample) and the higher loading of active species (in comparison to the modification with FeSO4.7H2O). ; 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/ST5/00269, from the National Science Centre (Poland). U.D. acknowledges the Spanish Government for funding (MAT2017-82288-C2-1-P).

[EN] Titanosilicate ferrierite zeolite (FER) and its delaminated form (ITQ-6), with various Si/Ti molar ratios, were synthetized and tested as catalysts for diphenyl sulfide (Ph2S) and dimethyl sulfide (DMS) oxidation with H2O2. The zeolites were characterized with respect to their chemical composition (ICP-OES), structure (XRD, UV-vis DRS) and texture (low-temperature N-2 adsorption-desorption). Titanium in the FER and ITQ-6 samples was present mainly in the zeolite framework with a significant contribution of titanium in the extraframework positions. Titanosilicate zeolites of FER and ITQ-6 series were found to be active catalysts of diphenyl and dimethyl sulfides oxidation by H2O2 to sulfoxides (Ph2SO/DMSO) and sulfones (Ph2SO2/DMSO2). The efficiency of these reactions depends on the porous structure of the zeolite catalysts - conversion of larger molecules of diphenyl sulfide was significantly higher in the presence of delaminated zeolite Ti-ITQ-6 due to the possibility of the interlayer mesopores penetration by reactants. On the other side diphenyl sulfide molecules are too large to be accommodated into micropores of FER zeolite. The efficiency of dimethyl sulfide conversion, due to relatively small size of this molecule, was similar in the presence of Ti-FER and Ti-ITQ-6 zeolites. For all catalysts, the organic sulfide conversion was significantly intensified under UV irradiation. It was suggested that Ti cations in the zeolite framework, as well as in the extraframework, species play a role of the single site photocatalysts active in the formation of hydroxyl radicals, which are known to be effective oxidants of the organic sulfides. ; The studies were carried out in the frame of project 2016/21/B/ST5/00242 from the National Science Centre (Poland). Part of the research was done with equipment purchased in the frame of European Regional Development Fund (Polish Innovation Economy Operational Program -contract no. POIG.02.01.00-12-023/08). U.D. acknowledges to the Spanish Government by the funding ...