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[EN] We studied the influence of the ethanol used as a washing solvent for obtaining swollen and pillared MWW topology zeolites with long-range ordering of lamellar structure. The diffractogram results showed that the increased number of washes increases the degree of order of the lamellar structure. Thermogravimetric results showed a considerable removal of the weakly interacting surfactant molecules after the third wash. The washes with ethanol did not remove the surfactant that strongly interacted with the MWW structure. The pillared material after the third wash showed a long-range ordering of the lamellar structure with the surface area of 728 m(2) g(-1), mesopore sizes of 2-4 nm and morphology characteristic of pillared MWW-type zeolites. ; Anderson Joel Schwanke is grateful the CAPES Foundation and PDSE program (process number 99999.004779/2014-02). Urbano Diaz acknowledges to the Spanish Government (MAT2014-52085-C2-1-P and MAT2017-82288-C2-1-P). ; Schwanke, AJ.; Díaz Morales, UM.; Corma Canós, A.; Pergher, S. (2019). The influence of ethanol-assisted washes to obtain swollen and pillared MWW-type zeolite with high degree ordering of lamellar structure. Microporous and Mesoporous Materials. 275:26-30. https://doi.org/10.1016/j.micromeso.2018.08.010 ; S ; 26 ; 30 ; 275 ; Corma, A. (1997). From Microporous to Mesoporous Molecular Sieve Materials and Their Use in Catalysis. Chemical Reviews, 97(6), 2373-2420. doi:10.1021/cr960406n ; IZA, International Zeolite Association, web page http://www.iza-structure.org/. ; Roth, W. J., Nachtigall, P., Morris, R. E., & Čejka, J. (2014). Two-Dimensional Zeolites: Current Status and Perspectives. Chemical Reviews, 114(9), 4807-4837. doi:10.1021/cr400600f ; Díaz, U., & Corma, A. (2014). Layered zeolitic materials: an approach to designing versatile functional solids. Dalton Transactions, 43(27), 10292. doi:10.1039/c3dt53181c ; Corma, A., Fornes, V., Pergher, S. B., Maesen, T. L. M., & Buglass, J. G. (1998). Delaminated zeolite precursors as selective acidic ...

[EN] A new route to obtain pillared, disordered or desilicated MWW-type zeolites was developed assisted by quaternary ammonium surfactants with different hydrocarbon tail size acting as swelling agents (C(12)TA(+), C(I6)TA(+), C(18)TA(+)) and TPA(+) both exchanged to their hydroxide forms instead of only one swelling agent (C(n)TA(+) or TPA(+)) in hydroxide form. Effect of surfactant concentration and swelling conditions were determinant to obtain MWW-type zeolites with different lamellar organization and spatial distribution of individual zeolitic layers. Specifically, soft swelling at 25 degrees C with C(12)TA(+) preserved layer structure reaching a final disordered/pillared structure while pillared structures are obtained in the case of materials swollen with C(16)TA(+) and C(18)TA(+). Aggressive swelling processes at 80 degrees C favored desilication, damaging the layers structure in case of C(12)TA(+) while pillared materials are obtained after swollen with C(16)TA(+) and C(18)TA(+) surfactants. It was proved that both swelling agents in hydroxide forms combining with swelling and pillaring procedure influenced on physico-chemical and morphological nature of MWW-type materials due to the particular conditions used. The obtained derivative MWW zeolites with different morphology, order and accessibility levels were firstly evaluated by catalytic dehydration of fructose to 5-hydroxymethylfurfural (5-HMF) showing superior activity compared to beta zeolites reported in literature. ; Anderson Joel Schwanke is grateful to CAPES Foundation and PDSE program (process number 99999.004779/2014-02) from Ministry of Education of Brazil. U.D and A.C acknowledge to the Spanish Government (Severo Ochoa program SEV-2012-0267 and MAT2014-52085-C2-1-P) and to the Generalitat Valenciana (Prometeo 11/2013-011) by the funding. The European Union is also acknowledged by ERC-AdG-2014-671093 - SynCatMatch. ; Schwanke, AJ.; Pergher, S.; Díaz Morales, UM.; Corma Canós, A. (2017). The influence of swelling agents molecular dimensions ...

The chemistry between layered MWW zeolite and carbon black pearls (BP 2000) as an inexpensive hard template was investigated to develop a rational one-pot synthesis of MCM-22 microspheres. The characterization results showed that the insertion of BP 2000 in the gel synthesis did not substantially compromise the crystallinity and microporosity, and the microscopic analyses showed that BP 2000 played a key role in controlling the final morphology of the MCM-22 zeolite, creating beautiful dandelion-like microspherical particles. The morphology obtained is due to the tortuous shape of the hard template, the particular MWW particle crystals, the interaction with the external surface of the MWW zeolitic precursor, and the synthesis conditions. The stacking of MWW crystals with edge-to-face orientations generates meso-/macrovoids, allowing access to the interiors of the microspheres. The microspheres were homogeneous with sizes ranging from 6 to 8 μm with an increase of the external surface and a macroporous size distribution centered at 200 nm, which is two times that of the traditional MCM-22 zeolite. ; A.J.S. is grateful to the CAPES Foundation and PDSE program (process number 99999.004779/2014-02) from the Ministry of Education of Brazil. U.D. and A.C. acknowledge funding by the Spanish Government (Severo Ochoa program SEV-2012-0267 and MAT2014-52085-C2-1-P) and the Generalitat Valenciana (Prometeo). The European Union is also acknowledged by ERC-AdG-2014-671093—SynCatMatch. S.P. and K.S. acknowledge the CAPES-CAFP project number 054/14.

[EN] The chemistry between layered MWW zeolite and carbon black pearls (BP 2000) as an inexpensive hard template was investigated to develop a rational one-pot synthesis of MCM-22 microspheres. The characterization results showed that the insertion of BP 2000 in the gel synthesis did not substantially compromise the crystallinity and microporosity, and the microscopic analyses showed that BP 2000 played a key role in controlling the final morphology of the MCM-22 zeolite, creating beautiful dandelion-like microspherical particles. The morphology obtained is due to the tortuous shape of the hard template, the particular MWW particle crystals, the interaction with the external surface of the MWW zeolitic precursor, and the synthesis conditions. The stacking of MWW crystals with edge-to-face orientations generates meso-/macrovoids, allowing access to the interiors of the microspheres. The microspheres were homogeneous with sizes ranging from 6 to 8 mu m with an increase of the external surface and a macroporous size distribution centered at 200 nm, which is two times that of the traditional MCM-22 zeolite ; A.J.S. is grateful to the CAPES Foundation and PDSE program (process number 99999.004779/2014-02) from the Ministry of Education of Brazil. U.D. and A.C. acknowledge funding by the Spanish Government (Severo Ochoa program SEV-2012-0267 and MAT2014-52085-C2-1-P) and the Generalitat Valenciana (Prometeo). The European Union is also acknowledged by ERC-AdG-2014-671093-SynCatMatch. S.P. and K.S. acknowledge the CAPES-CAFP project number 054/14. ; Schwanke, A.; Villarroel-Rocha, J.; Sapag, K.; Díaz Morales, UM.; Corma Canós, A.; Pergher, S. (2018). Dandelion-Like Microspherical MCM-22 Zeolite Using BP 2000 as a Hard Template. ACS Omega. 3(6):6217-6223. https://doi.org/10.1021/acsomega.8b00647 ; S ; 6217 ; 6223 ; 3 ; 6

This is the peer reviewed version of the following article: A. J. Schwanke, R. Balzer, C. Wittee Lopes, D. Motta Meira, U. Díaz, A. Corma, S. Pergher, Chem. Eur. J. 2020, 26, 10459, which has been published in final form at https://doi.org/10.1002/chem.202000862. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving. ; [EN] In this work, an MWW-type zeolite with pillars containing silicon and niobium oxide was synthesized to obtain a hierarchical zeolite. The effect of niobium insertion in the pillaring process was determined by combining a controllable acidity and accessibility in the final material. All pillared materials had niobium occupying framework positions in pillars and extra-framework positions. The pillared material, Pil-Nb-4.5 with 4.5 wt % niobium, did not compromise the mesoporosity formed by pillaring, while the increase of niobium in the structure gradually decreased the mesoporosity and ordering of lamellar stacking. The morphology of the pillared zeolites and the niobium content were found to directly affect the catalytic activity. Specifically, we report on the activity of the MWW-type zeolites with niobium catalyzing the gas-phase oxidation of volatile organic compounds (VOCs), which is an important reaction for clean environmental. All produced MWW-type zeolites with niobium were catalytically active, even at low temperatures and low niobium loading, and provided excellent conversion efficiencies. ; A.J.S. thanks the CordenacAo de Aperfeicoamento de Pessoal de Nivel Superior-Brasil (CAPES)-Finance Code 001, the PDSE program (process number 99999.004779/2014-02) and the prof. Claudio Radtke from the PPGQ-UFRGS for the XPS analyses. C.W.L. is grateful to INOMAT/CAPES for a postdoctoral fellowship. U.D. thanks the funding by the Spanish Government (MAT2017-82288-C2-1-P). ; Schwanke, AJ.; Balzer, R.; Lopes, CW.; Meira, DM.; Díaz Morales, UM.; Corma Canós, A.; Pergher, S. (2020). A Lamellar MWW Zeolite With Silicon and Niobium Oxide ...