OSDA-free synthesis of MTW-type zeolite from sodium aluminosilicate gels with zeolite beta seeds

Yoshihiro Kamimura, Kenta Iyoki, Shanmugam Palani Elangovan, Keiji Itabashi, Atsushi Shimojima, Tatsuya Okubo

Research output: Contribution to journalArticle

54 Citations (Scopus)

Abstract

Seed-assisted methods have provided a new route for the organic structure-directing agent (OSDA)-free synthesis of industrially valuable zeolites. In the present study, we have reported the discovery of the OSDA-free synthesis of ZSM-12 (MTW-type zeolite) by adding calcined zeolite beta seed crystals to the OSDA-free Na-aluminosilicate gel. Various parameters in this synthesis have been comprehensively investigated. Characterization by XRD, FE-SEM, ICP-AES, and 27Al MAS NMR showed that the obtained MTW products without impurity (SiO 2/Al 2O 3 = 31.8-46.4) possessed high crystallinity and a well-defined rod-like morphology. Adsorption-desorption isotherm of water and NH 3-TPD profiles of MTW product showed enough adsorption capacity for water and ammonia molecules, respectively. Moreover, considering the crystallization behavior of seeded and non-seeded Na-aluminosilicate gels, the following key factors were found for inducing the crystallization of MTW by zeolite beta seeds under the hydrothermal condition: the structural similarity between seeds and target zeolite, and the initial gel compositions that provide specific aluminosilicate precursors for the crystallization of MTW prior to the spontaneous nucleation of other zeolite. This methodology provides a promising approach toward designed syntheses of valuable zeolites under environmentally benign conditions.

Original languageEnglish
Pages (from-to)282-290
Number of pages9
JournalMicroporous and Mesoporous Materials
Volume163
DOIs
Publication statusPublished - 2012 Nov 15
Externally publishedYes

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Keywords

  • Crystallization
  • MTW-type zeolite
  • Organic structure-directing agent (OSDA)-free
  • Seed-assisted synthesis
  • Zeolite beta

ASJC Scopus subject areas

  • Materials Science(all)
  • Mechanics of Materials
  • Chemistry(all)
  • Condensed Matter Physics

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