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A two-dimensional zeolite with the topol. of MWW sheets has been obtained by direct synthesis with a combination of two org. structure-directing agents. The resultant material consists of approx. 70 % single and double layers and displays a well-structured external surface area of about 300 m2 g-1. The delaminated zeolite prepd. by means of this single-step synthetic route has a high delamination degree, and the structural integrity of the MWW layers is well preserved. The new zeolite material displayed excellent activity, selectivity, and stability when used as a catalyst for the alkylation of benzene with propylene and found to be superior to the catalysts that are currently used for producing cumene. ; Financial support by the Spanish Government-MINECO through "Severo Ochoa" (SEV 2012-0267), Consolider Ingenio 2010-Multicat, and MAT2012-31657 is acknowledged. M.E.M.-A. thanks MINECO for financial support through a pre-doctoral fellowship (BES-2013-066800). ; Margarit Benavent, VJ.; Martínez Armero, ME.; Navarro Villalba, MT.; Martínez, C.; Corma Canós, A. (2015). Direct Dual-Template Synthesis of MWW Zeolite Monolayers. Angewandte Chemie International Edition. 54(46):13724-13728. https://doi.org/10.1002/anie.201506822 ; S ; 13724 ; 13728 ; 54 ; 46

[EN] ITQ-39, a multipore zeolite with interconnected 12- and 10-ring channel systems, effectively catalyzes the alkylation of two low value naphtha fractions for the production of diesel range alkylaromatics. A catalytic and molecular dynamics study allows us to conclude that its higher selectivity to the desired diesel fraction and, especially, its longer catalyst life as compared to beta or MCM-22, conventionally used as heterogeneous alkylation catalysts, are due to the combined contribution of its small nano-sized crystallites, moderate Bronsted acidity and unique framework topology. The small diffusion coefficients obtained for alkylaromatics on ITQ-39 as compared to those corresponding to the large pore beta zeolite evidence the significant diffusional problems of most of the reactants and products through the channels of the ITQ-39 structure. Thus, alkylation reactions on this zeolite seem to occur mainly on the most external acid sites (external surface, pore mouths), whereas the zeolite structure contributes positively by preventing undesired reactions to occur, which would result in lower selectivity to the monoalkylated products and in a faster catalyst deactivation. ; Financial support by the Spanish Government-MINECO through "Severo Ochoa" (SEV 2012-0267), Consolider Ingenio 2010-Multicat, MAT2012-37160 and MAT2012-31657, by the European Union through ERC-AdG-2014-671093 - SynCatMatch and by the Generalitat Valenciana through the Prometeo program (PROME-TEOII/2013/011) is acknowledged. Repsol is thanked for financial support and permission to publish these results. G.S. thanks ASIC-UPV for computing time. The Electron Microscopy Service of the UPV is acknowledged for their help in samples characterization. ; Martínez Armero, ME.; Moliner Marin, M.; Sastre Navarro, GI.; Rey Garcia, F.; Martínez, C.; Corma Canós, A. (2016). ITQ-39 zeolite, an efficient catalyst for the conversion of low value naphtha fractions into diesel fuel: The role of pore size on molecular diffusion and reactivity. Journal of ...

[EN] An efficient synthesis methodology to obtain homogeneous nanosized high-silica Beta zeolites ( 10¿20 nm) with high solid yields (above 95%) using simple alkyl-substituted flexible dicationic OSDAs is described. These dicationic OSDAs allow the synthesis of nanosized Beta zeolites with different Si/Al ratios (15¿30) in alkaline and fluoride media, resulting in nanocrystalline materials with different physicochemical properties. These nanosized Beta zeolites show better catalytic behavior towards the industrially-relevant alkylation of benzene with propylene to obtain cumene compared with other commercially available nanosized Beta zeolites. ; Financial support from the Spanish Government-MINECO through "Severo Ochoa" (SEV 2012-0267), Consolider Ingenio 2010-Multicat, MAT2012-37160 and, MAT2012-31657 is acknowledged. The European Union is also acknowledged by the SynCatMatch project (ERC-AdG-2014-671093). M.E.M-A. thanks MINECO for economical support through a pre-doctoral fellowship (BES-2013-066800). ; Martínez Franco, R.; Paris-Carrizo, CG.; Martínez Armero, ME.; Martínez, C.; Moliner Marin, M.; Corma Canós, A. (2015). High-silica nanocrystalline Beta zeolites: efficient synthesis and catalytic application. Chemical Science. 7(1):102-108. https://doi.org/10.1039/c5sc03019f ; S ; 102 ; 108 ; 7 ; 1

[EN] Nano-crystalline MCM-22 zeolite was synthesized in a one-pot procedure by the use of an organosilane (dimethyl-octadecyl-(3-trimethoxysilylpropyl)-ammonium chloride, TPOAC) in the zeolite synthesis gel. This crystal growth inhibition procedure introduced mesopores in the MCM-22 crystallites. The lower mechanical stability of the nano-crystalline MCM-22 zeolite compared with bulk MCM-22 can be countered to some extent by pillaring. The increased external surface of the microporous zeolite domains resulted in increased accessibility of the Bronsted acid sites, as followed from the better performance in liquid-phase benzene alkylation with propylene as compared with bulk MCM-22. The increased accessibility of the internal acid sites in Mo-loaded hierarchical MCM-22 was also evident from the improved benzene selectivity during methane aromatization. Silylation of hierarchical Mo/MCM-22 was detrimental for the catalytic performance in MDA. The nano-crystalline MCM-22 has physico-chemical and catalytic properties intermediate between those of MCM-22 and ITQ-2 with the benefit over ITQ-2 that it can be synthesized in a single step. (C) 2015 Elsevier Inc. All rights reserved. ; Funding from the 7th Framework Program of the European Commission through the Collaborative Project Next-GTL (agreement no 229183) and financial support by the Spanish Government-MINECO through "Severo Ochoa" (SEV 2012-0267), Consolider Ingenio 2010-Multicat (CSD2009-00050) and MAT2012-31657 are acknowledged. Marta E. Martinez Armero thanks MINECO for economical support through pre-doctoral fellowship for doctors training (BES-2013-066800). The authors thank B. Esparcia for technical assistance. ; Tempelman, CHL.; Portilla Ovejero, MT.; Martínez Armero, ME.; Mezari, B.; De Caluwe, NGR.; Martínez, C.; Hensen, EJM. (2016). One-pot synthesis of nano-crystalline MCM-22. Microporous and Mesoporous Materials. 220:28-38. https://doi.org/10.1016/j.micromeso.2015.08.018 ; S ; 28 ; 38 ; 220

[EN] The synthesis of the ZSM-5 and beta zeolites in their nanosized form has been achieved by using simple alkyl-substituted mono-cationic cyclic ammonium cations as OSDA molecules. The particular combination of a cyclic fragment and a short linear alkyl-chain group (preferentially C4) within the monocationic OSDA molecules allows directing the crystallization of nanosized zeolites with excellent solid yields (above 90%). Interestingly, the formation of the nanosized ZSM-5 and beta zeolites mostly depends on the size and nature of the cyclic fragment of the OSDA molecule, resulting in all cases in nanocrystalline solids with homogeneous distributions of particle sizes (similar to 10-25 nm) and controlled Si/Al molar ratios (similar to 15-30). The achieved nanosized ZSM-5 and beta zeolites have been extensively characterized by different techniques to study their physico-chemical properties, such as chemical composition, pore accessibility or Bronsted acidity, among others. Moreover, the catalytic properties of the nanosized ZSM-5 and beta zeolites have been evaluated for different chemical reactions, including methanol-to-olefins (MTO) in the case of ZSM-5, and alkylation of benzene with propylene to obtain cumene and oligomerization of light olefins to liquid fuels in the case of beta, observing in all cases improved catalytic activity and product selectivity towards target products when compared to related catalysts. ; This work has been supported by the Spanish Government-MINECO through "Severo Ochoa" (SEV 2012-0267), MAT2015-71261-R and CTQ2015-70126-R, by the European Union through ERC-AdG-2014-671093 (SynCatMatch) and by the Fundacion Ramon Areces through a research contract of the "Life and Materials Science" program. E. M. G. and M. R. D-R. acknowledge "La Caixa - Severo Ochoa" International PhD Fellowships (call 2015). M. E. M-A. thanks MINECO for economical support through pre-doctoral fellowship (BES-2013-066800). The Electron Microscopy Service of the UPV is acknowledged for their help in sample ...