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A multi-dimensional extra-large pore silicogermanate zeolite, named ITQ-54, has been synthesised by in situ decomposition of the N,N-dicyclohexylisoindolinium cation into the N-cyclohexylisoindolinium cation. Its structure was solved by 3D rotation electron diffraction (RED) from crystals of ca. 1 μm in size. The structure of ITQ-54 contains straight intersecting 20 × 14 × 12-ring channels along the three crystallographic axes and it is one of the few zeolites with extra-large channels in more than one direction. ITQ-54 has a framework density of 11.1 T atoms per 1000 Å3, which is one of the lowest among the known zeolites. ITQ-54 was obtained together with GeO2 as an impurity. A heavy liquid separation method was developed and successfully applied to remove this impurity from the zeolite. ITQ-54 is stable up to 600 °C and exhibits permanent porosity. The structure was further refined using powder X-ray diffraction (PXRD) data for both as-made and calcined samples. ; This work was supported by the Spanish Government (MAT2012-38567-C02-01, Consolider Ingenio 2010-Multicat CSD-2009-00050 and Severo Ochoa SEV-2012-0267), Generalitat Valenciana (Project Prometeo), the Swedish Research Council (VR), the Swedish Governmental Agency for Innovation Systems (VINNOVA) and the Knut & Alice Wallenberg Foundation through a grant for purchasing the TEMs and the project grant 3DEM-NATUR. Y. F. Yun thanks the China Scholarship Council (CSC). The authors acknowledge ESRF, Grenoble for the use of the beamline ID31 and the mail-in system of 11-BM at the Advanced Photon Source, Argonne National Laboratory, USA. ; Jiang, J.; Yun, Y.; Zou, X.; Jorda Moret, JL.; Corma Canós, A. (2015). ITQ-54: a multi-dimensional extra-large pore zeolite with 20 × 14 × 12-ring channels. Chemical Science. 6(1):480-485. https://doi.org/10.1039/c4sc02577f ; S ; 480 ; 485 ; 6 ; 1 ; Davis, M. E. (2002). Ordered porous materials for emerging applications. Nature, 417(6891), 813-821. doi:10.1038/nature00785 ; Atienzar, P., Díaz-Cabañas, M. J., Moliner, ...

A multidimensional extra-large pore germanosilicate, denoted ITQ-56, has been synthesized by using modified memantine as an organic structure-directing agent. ITQ-56 crystallizes as plate-like nanocrystals. Its structure was determined by 3D electron diffraction/MicroED. The structure of ITQ-56 contains extra-large 22-ring channels intersecting with straight 12-ring channels. ITQ-56 is the first zeolite with 22-ring pores, which is a result of ordered vacancies of double 4-ring (d4r) units in a fully connected zeolite framework. The framework density is as low as 12.4 T atoms/1000 Å3. The discovery of the ITQ-56 structure not only fills the missing member of extra-large pore zeolite with 22-ring channels but also creates a new approach of making extra-large pore zeolites by introducing ordered vacancies in zeolite frameworks. ; This work has been supported by the European Union through ERC-AdG-2014-671093 (SynCatMatch), by the Spanish Government-MINECO through "Severo Ochoa" (SEV-2016-0683), the Swedish Research Council (VR, 2017-04321, 2019-05465), and the Knut & Alice Wallenberg Foundation through the project grant 3DEM-NATUR (KAW, 2012-0112). The EM facility was supported by the Knut and Alice Wallenberg Foundation. J.J. thanks the National Natural Science Foundation 21971259.

Aluminosilicate boggsite (Si/Al-BOG) has been hydrothermally synthesized without adding organic structure-directing agents (OSDAs) in the synthesis gel using the borosilicogermanium ITQ-47 (Si/B-ITQ-47) zeolite as seeds. The introduction of the costly and environmentally less benign phosphazene organic structure-directing agent is not required to grow the zeolite. Physicochemical characterization experiments show that Si/Al-BOG has good crystallinity, high surface area, tetrahedral Al3+ species, and acid sites. In order to test the catalytic performance of the zeolite, the synthesis of L,L-lactide from L-lactic acid was performed. Si/Al-BOG exhibits 88.2% conversion of L-lactic acid and 83.8% L,L-lactide selectivity, which are better than those of other zeolites studied up to now. ; This work was supported by the National Natural Science Foundation of China 21971259 and 91645112, The Natural Science Foundation of Hubei Province of China (2014CFA043), and the Key Research Program of Frontier Sciences, CAS (No. QYZDB-SSW-SLH026). The European Union is also acknowledged by ERC-AdG-2014-671093 SynCatMatch, and the Spanish Government through "Severo Ochoa" (SEV-2016-0683, MINECO). Q. H. acknowledges the International Program Fund for doctoral students, Sun Yat-sen University, for scholarships in Spain. ; Peer reviewed

[EN] Aluminosilicate boggsite (Si/Al-BOG) has been hydrothermally synthesized without adding org. structure-directing agents (OSDAs) in the synthesis gel using the borosilicogermanium ITQ-47 (Si/B-ITQ-47) zeolite as seeds. The introduction of the costly and environmentally less benign phosphazene org. structure-directing agent is not required to grow the zeolite. Physicochem. characterization expts. show that Si/Al-BOG has good crystallinity, high surface area, tetrahedral Al3+ species, and acid sites. In order to test the catalytic performance of the zeolite, the synthesis of L,L-lactide from L-lactic acid was performed. Si/Al-BOG exhibits 88.2% conversion of L-lactic acid and 83.8% L,L-lactide selectivity, which are better than those of other zeolites studied up to now. ; This work was supported by the National Natural Science Foundation of China 21971259 and 91645112, The Natural Science Foundation of Hubei Province of China (2014CFA043), and the Key Research Program of Frontier Sciences, CAS (No. QYZDB-SSW-SLH026). The European Union is also acknowledged by ERC-AdG-2014-671093 SynCatMatch, and the Spanish Government through "Severo Ochoa" (SEV-2016-0683, MINECO). Q. H. acknowledges the International Program Fund for doctoral students, Sun Yat-sen University, for scholarships in Spain. ; Huang, Q.; Chen, N.; Liu, L.; Arias-Carrascal, KS.; Iborra Chornet, S.; Yi, X.; Ma, C. (2020). Direct synthesis of the organic and Ge free Al containing BOG zeolite (ITQ-47) and its application for transformation of biomass derived molecules. Chemical Science. 11(44):12103-12108. https://doi.org/10.1039/d0sc04044d ; S ; 12103 ; 12108 ; 11 ; 44 ; Cundy, C. S., & Cox, P. A. (2003). The Hydrothermal Synthesis of Zeolites: History and Development from the Earliest Days to the Present Time. Chemical Reviews, 103(3), 663-702. doi:10.1021/cr020060i ; C. Baerlocher and L. B.McCusker , Database of Zeolite Structures , http://www.iza-structure.org/databases/ , accessed June 8, 2018 ; Lobo, R. F., Pan, M., Chan, I., Medrud, R. C., ...

12103 12108 11 44 ; S ; [EN] Aluminosilicate boggsite (Si/Al-BOG) has been hydrothermally synthesized without adding org. structure-directing agents (OSDAs) in the synthesis gel using the borosilicogermanium ITQ-47 (Si/B-ITQ-47) zeolite as seeds. The introduction of the costly and environmentally less benign phosphazene org. structure-directing agent is not required to grow the zeolite. Physicochem. characterization expts. show that Si/Al-BOG has good crystallinity, high surface area, tetrahedral Al3+ species, and acid sites. In order to test the catalytic performance of the zeolite, the synthesis of L,L-lactide from L-lactic acid was performed. Si/Al-BOG exhibits 88.2% conversion of L-lactic acid and 83.8% L,L-lactide selectivity, which are better than those of other zeolites studied up to now. This work was supported by the National Natural Science Foundation of China 21971259 and 91645112, The Natural Science Foundation of Hubei Province of China (2014CFA043), and the Key Research Program of Frontier Sciences, CAS (No. QYZDB-SSW-SLH026). The European Union is also acknowledged by ERC-AdG-2014-671093 SynCatMatch, and the Spanish Government through "Severo Ochoa" (SEV-2016-0683, MINECO). Q. H. acknowledges the International Program Fund for doctoral students, Sun Yat-sen University, for scholarships in Spain. Huang, Q.; Chen, N.; Liu, L.; Arias-Carrascal, KS.; Iborra Chornet, S.; Yi, X.; Ma, C. (2020). Direct synthesis of the organic and Ge free Al containing BOG zeolite (ITQ-47) and its application for transformation of biomass derived molecules. Chemical Science. 11(44):12103-12108. https://doi.org/10.1039/d0sc04044d Cundy, C. S., & Cox, P. A. (2003). The Hydrothermal Synthesis of Zeolites: History and Development from the Earliest Days to the Present Time. Chemical Reviews, 103(3), 663-702. doi:10.1021/cr020060i C. Baerlocher and L. B.McCusker , Database of Zeolite Structures , http://www.iza-structure.org/databases/ , accessed June 8, 2018 Lobo, R. F., Pan, M., Chan, I., Medrud, R. C., Zones, S. I., ...