Constrained Al sites in FER-type zeolites
Constrained Al sites in FER-type zeolites
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DOI：
10.1016/s1872-2067(21)63884-6
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发表时间：
2021-11-01
影响因子：
16.5
通讯作者：
Zhu, Xiangxue
中科院分区：
文献类型：
--
作者：
Chu, Weifeng;Liu, Xiaona;Zhu, Xiangxue
沸石中布朗斯台德酸（Si-OH-Al）的晶体位点与Al位点密切相关，在催化应用中发挥着重要而独特的作用，特别是当它们分布在开放通道系统中或限制在具有小孔开口的空腔中时。在本文中，我们通过针对粉末 X 射线衍射数据的 Rietveld 精修，揭示了 FER 型沸石中包含独特局部环境（10 环通道和镁碱沸石空腔）的受限 Al 晶体位点。最终的精修表明，无论使用何种类型的结构导向剂和合成介质，T1和/或T3都是富铝位置，这通过理论计算得到进一步证实。 FER型沸石中受限Al位点的这一新发现可以很好地解释其在DME羰基化反应中有限的催化活性。 (C)2021，中国科学院大连化学物理研究所。由 Elsevier B.V. 出版。保留所有权利。
Crystallographic sites of Bronsted acids (Si-OH-Al) in zeolites, which are closely associated with the Al sites, play a significant and unique role in the catalytic application, especially when they are distributed in open channel systems or confined in cavities with small pore openings. In this article, we unraveled constrained Al crystallographic sites in FER-type zeolites containing the distinct local environments (10-ring channels and ferrierite cavities) by Rietveld refinement against the powder X-ray diffraction data. Final refinement demonstrates that regardless of the types of structure-directing agents and synthetic medium utilized, T1 and/or T3 are Al-rich positions, which are further confirmed by theoretical calculations. This new finding of constrained Al sites in the FER-type zeolite can well explain its limited catalytic activity in the DME carbonylation reaction. (C) 2021, Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.