Elucidation of Nucleation -Crystal Growth Mechanism of Zeolites in an Atomic Scale, and its Application to Novel Process

原子尺度上沸石成核-晶体生长机制的阐明及其在新工艺中的应用

• 批准号: 13450325
• 负责人: OKUBO Tatsuya
• 金额: $ 9.79万
• 依托单位: THE UNIVERSITY OF TOKYO
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2001
• 资助国家: 日本
• 起止时间: 2001 至 2002
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-13450325/
• 关键词: ZEOLITE; NUCLEATION; CRYSTAL GROWTH; AFM; 前駆体; ナノ構造; 核発成; 短結晶; 小角X線散乱

The objectives of this study are elucidation of crystal growth mechanism of LTA and FAU zeolites in an atomic scale, and the development of the rational synthesis process based on the mechanism.In the first year, the detection of precursor and its contribution to the crystal growth in dilute system was focused. The same positions on the top surface of the seed crystals were repeatedly observed in the course of the growth. In one solution, LTA was grown on LTA, and FAU was grown on FAU. When Al content was reduced, LTA was grown on LTA, but FAU was unchanged. The solution was characterized by Raman spectroscopy. As the Al content was reduced, the ration of 4MR to 6MR was increased. These experimental results were accounted for by assuming that the precursor of LTA was 4MR, and that of FAU was 6MR.In the second year, further investigation was performed on the crystal growth. By observing the top surface carefully, the structure of the growing surface was elucidated. These results also supported that the precursor of LTA was 4MR, and that of FAU was 6MR. The species in the solution was characterized by novel method. High-Energy X-ray Diffraction (HE-XRD) of gel was performed at Spring-8 SR facility. We first succeeded in demonstrating that there are differences in the ring structure before crystallization.

本研究的目的是在原子尺度上阐明LTA和FAU分子筛的晶体生长机理，并在此基础上发展合理的合成工艺。在生长过程中反复观察晶种顶面上的相同位置。在一种溶液中，LTA在LTA上生长，FAU在FAU上生长。当Al含量降低时，LTA在LTA上生长，但FAU不变。通过拉曼光谱对溶液进行表征。随着Al含量的降低，4 MR/6 MR的比值增加。实验中假设LTA的前驱体为4 MR，FAU的前驱体为6 MR。第二年，我们对晶体生长进行了进一步的研究。通过仔细观察顶面，阐明了生长表面的结构。这些结果也支持LTA的前体是4 MR，FAU的前体是6 MR。采用新的方法对溶液中的物种进行了表征。凝胶的高能X射线衍射（HE-XRD）在Spring-8 SR设施中进行。我们首先成功地证明了在结晶之前环结构存在差异。

项目成果

Toru Wakihara, Tatsuya Okubo: "Crystal Growth Behavior of Zeolites Elucidated by Atomic Force Microscopy"Journal of Chemical Engineering of Japan. (印刷中). (2004)

Toru Wakihara、Tatsuya Okubo：“原子力显微镜阐明的沸石晶体生长行为”日本化学工程杂志（2004 年出版）。

Masaru Ogura et al.: "Aluminosilicate Species in the Hydrogel Phase Formed during the Aging Process for Crystallization of FAU Zeolite"Chemistry of Materials. 15. 2661-2667 (2003)

Masaru Ogura 等人：“FAU 沸石结晶老化过程中形成的水​​凝胶相中的铝硅酸盐物质”材料化学。

Masaru Ogura, Yasuyuki Kawazu, Hiroshi Takahashi, Tatsuya Okubo: "Aliminosilicate Species in the Hydrogel Phase Formed during the Aging Process for the Crystallization of FAU Zeolite"Chemistry of Materials. 15. 2661-2667 (2003)

Masaru Ogura、Yasuyuki Kawazu、Hiroshi Takahashi、Tatsuya Okubo：“FAU 沸石结晶老化过程中形成的水​​凝胶相中的硅酸铝物质”材料化学。

Toru Wakihara, Tatsuya Okubo: "Crystal Growth Behavior of Zeolites Elucidated by Atomic Force Microscopy."Journal of Chemical Engineering of Japan. (2004)

Toru Wakihara、Tatsuya Okubo：“原子力显微镜阐明的沸石晶体生长行为。”日本化学工程杂志。

Toru Wakihara, Akira Sugiyama, Tatsuya Okubo: "Crystal Growth of Faujasite Observed by Atomic Force Microscopy"Microporous and Mesoporous Materials. (2004)

Toru Wakihara、Akira Sugiyama、Tatsuya Okubo：“原子力显微镜观察八面沸石的晶体生长”微孔和介孔材料。