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3D Electron Diffraction Unravels the New Zeolite ECNU-23 from the “Pure” Powder Sample of ECNU-21 |
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| Authors: | Dr Xue Liu Dr Yi Luo Wenting Mao Dr Jingang Jiang Dr Hao Xu Prof Lu Han Prof Junliang Sun Prof Peng Wu |
| Institution: | 1. Shanghai Key Laboratory of Green Chemistry and Chemical Processes, School of Chemistry and Molecular Engineering, East China Normal University, North Zhongshan Road 3663, Shanghai, 200062 P. R. China
College of Science, Agricultural University of Hebei, Lingyusi Road 289, Baoding, 071001 P. R. China These authors contributed equally to this work.;2. Department of Materials and Environmental Chemistry, Stockholm University, 10691 Stockholm, Sweden These authors contributed equally to this work.;3. State Key Laboratory of Metal Matrix Composites, School of Chemistry and Chemical Engineering, Shanghai Jiao Tong University, Dongchuan Road 800, Shanghai, 200240 P. R. China;4. Shanghai Key Laboratory of Green Chemistry and Chemical Processes, School of Chemistry and Molecular Engineering, East China Normal University, North Zhongshan Road 3663, Shanghai, 200062 P. R. China;5. School of Chemical Science and Engineering, Tongji University, Siping Road 1239, Shanghai, 200092 P. R. China;6. Department of Materials and Environmental Chemistry, Stockholm University, 10691 Stockholm, Sweden |
| Abstract: | A novel crystalline high-silica zeolite with 12×8-membered ring (R) channel system is prepared with the aid of the 3D electron diffraction (3D ED) technique. A crystal with the same topology as one of the predicted daughter structures of CIT-13 germanosilicate, named ECNU-23 (East China Normal University 23) was coincidentally detected by the 3D ED investigation during the structure characterization of the “pure” powder sample of existing one-dimension (1D) 10-R ECNU-21. By controlling the alkaline-assisted hydrolysis under moderate conditions, we purified the phase of ECNU-23 by selectively breaking and removing the chemically weak Ge(Si)-O-Ge and metastable Si-O-Si bonds. Its structure was determined based on the 3D ED data, and confirmed by high-resolution TEM images and powder X-ray diffraction (PXRD) data. The aluminosilicate Al-ECNU-23 shows unique catalytic properties in the isomerization/ disproportionation of m-xylene as solid-acid catalyst. |
| Keywords: | 3D-Elektronenbeugung Alkalische Behandlung Heterogene Katalyse Zeolithe Strukturaufklärung |