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ITQ-54: a multi-dimensional extra-large pore zeolite with 20 × 14 × 12-ring channels.

ABSTRACT: 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 ?m 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.

SUBMITTER: Jiang J

PROVIDER: S-EPMC5811170 | biostudies-literature | 2015 Jan

REPOSITORIES: biostudies-literature

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ITQ-54: a multi-dimensional extra-large pore zeolite with 20 × 14 × 12-ring channels.

Jiang Jiuxing J Yun Yifeng Y Zou Xiaodong X Jorda Jose Luis JL Corma Avelino A

Chemical science 20141008 1

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 ...[more]

PMID: 29560171

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