Rapid tuning of ZSM-5 crystal size by using polyethylene glycol or colloidal silicalite-1 seed
Rapid tuning of ZSM-5 crystal size by using polyethylene glycol or colloidal silicalite-1 seed
复制标题
使用聚乙二醇或胶体silicalite-1晶种快速调节ZSM-5晶体尺寸
DOI：
10.1016/j.micromeso.2012.07.030
复制
发表时间：
2012-11
影响因子：
5.2
通讯作者：
Weibin Fan
中科院分区：
文献类型：
--
作者：
Feng Xu;Mei Dong;Weiyong Gou;Junfen Li;Zhangfeng Qin;Jianguo Wang;Weibin Fan
采用两种方法控制硅溶胶合成ZSM-5沸石的晶粒尺寸。一种是使用有机添加剂，另一种是使用胶体silicalite-1种子。在合成凝胶中加入聚乙二醇（PEG）有利于形成相对小的均匀晶体，因为它促进成核并以某种方式阻碍晶体的生长，尽管它对结构、结晶度、酸度和晶体形状几乎没有影响。所制备的催化剂在甲醇制烃（MTH）反应中显示出比用无PEG凝胶合成的样品更高的催化稳定性。通过在硅质岩-1晶种周围外延生长ZSM-5晶体，实现了不同尺寸ZSM-5晶体的精细可控合成。通过调节晶化时间和晶种加入量，可以使硅沸石-1的晶粒尺寸在200 ~ 1000 nm之间以每100 nm为单位进行调节。这为系统地研究分子筛晶粒大小对其催化性能的影响和调节产物分布提供了可能。ZSM-5催化MTH反应的稳定性随晶粒尺寸的减小而显著提高。晶体尺寸约为270 nm，其催化寿命分别是无PEG和有PEG时合成的样品的6倍和3倍。
Two methods were used to control the crystal size of ZSM-5 synthesized with commercial silica sol. One is use of organic additives; the other is use of colloidal silicalite-1 seed. Addition of polyethylene glycol (PEG) to the synthesis gel favors the formation of relatively small uniform crystals because of promotion of nucleation and somehow hindering the growth of crystals, although it has little influence on the structure, crystallinity, acidity, and crystal shape. The prepared catalyst shows higher catalytic stability than the sample synthesized with the PEG-free gel in the methanol-to-hydrocarbon (MTH) reaction. Finely controllable synthesis of different-sized ZSM-5 crystals was realized by epitaxially growing ZSM-5 crystals around colloidal silicalite-1 seed. The crystal size could be tuned from 200 to 1000nm by every 100nm through adjusting the crystallization time and the amount of the added silicalite-1 seed. This makes it possible to systematically study the effect of zeolite crystal size on its catalytic performance and tune product distribution. A significant increase in the catalytic stability was observed with decreasing crystal size for ZSM-5 catalyzing MTH reaction. The crystals with a size of about 270nm showed a catalytic life of about 6 and 3 times as long as those of the samples synthesized in the absence and presence of PEG respectively.
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DOI：
10.1016/s0927-6513(97)00014-x
发表时间：
1997-07
期刊：
Microporous Materials
影响因子：
--
作者：
R. Wendelbo;R. Roque-Malherbe
通讯作者：
R. Wendelbo;R. Roque-Malherbe
影响因子：
7.3
作者：
K. Beschmann;L. Riekert
通讯作者：
K. Beschmann;L. Riekert
DOI：
10.1016/s0144-2449(96)00134-0
发表时间：
1997-02
期刊：
Zeolites
影响因子：
--
作者：
B. Schoeman
通讯作者：
B. Schoeman
影响因子：
5.2
作者：
Li, Q;Creaser, D;Sterte, J
通讯作者：
Sterte, J
影响因子：
9.9
作者：
Guo, W;Luo, GS;Wang, YJ
通讯作者：
Wang, YJ