Crystallization behavior of zeolite beta in OSDA-free, seed-assisted synthesis

Yoshihiro Kamimura, Shinya Tanahashi, Keiji Itabashi, Ayae Sugawara, Toru Wakihara, Atsushi Shimojima, Tatsuya Okubo*


研究成果: Article査読

177 被引用数 (Scopus)


Recent reports on the organic structure-directing agent (OSDA)-free synthesis of some zeolites with the aid of seed crystals have opened a new way to the robust and environmentally friendly production of industrially valuable zeolites. However, the details on the crystallization behavior as well as the role of the seeds have not been fully clarified yet. In this study, the crystallization process of zeolite beta in the OSDA-free, seed-embedded Na +-aluminosilicate gel system, which never yields beta in the absence of the seeds, is investigated in detail. The XRD and TEM studies of the solid aluminosilicate products in the course of the hydrothermal treatment suggest that the crystallization of zeolite beta proceeds on the outer surface of amorphous aluminosilicates. The Raman spectroscopy, solid-state 27Al and 23Na MAS NMR and high-energy XRD analyses of seeded and nonseeded amorphous materials just before crystallization reveal that the beta seeds induce no major changes in their structures, implying that the nucleation of beta does not occur directly from the amorphous phase. The intermediate addition of the seeds after prehydrothermal treatment of a nonseeded gel enhances the crystallization rate and results in the increased number of beta crystals with smaller size. It is elucidated that, during the hydrothermal treatment, the beta seeds embedded in the gel provide crystal growth surface after they are exposed and/or released to the liquid phase by partial dissolution of the amorphous aluminosilicates. These findings provide a promising approach to the designed syntheses of valuable zeolites in the completely OSDA-free system.

ジャーナルJournal of Physical Chemistry C
出版ステータスPublished - 2011 1月 27

ASJC Scopus subject areas

  • 電子材料、光学材料、および磁性材料
  • エネルギー一般
  • 物理化学および理論化学
  • 表面、皮膜および薄膜


「Crystallization behavior of zeolite beta in OSDA-free, seed-assisted synthesis」の研究トピックを掘り下げます。これらがまとまってユニークなフィンガープリントを構成します。