期刊
MICROPOROUS AND MESOPOROUS MATERIALS
卷 74, 期 1-3, 页码 11-21出版社
ELSEVIER SCIENCE BV
DOI: 10.1016/j.micromeso.2004.06.002
关键词
crystallization mechanism; wetness-impregnation; Fe-silicalite; phenol; catalytic wet peroxide oxidation
The crystallization mechanism of Fe-MFI zeolite synthesized from amorphous Fe2O3-SiO2 xerogels wetness impregnated with aqueous TPAOH solutions has been studied. Samples with different degrees of crystallinity were prepared and characterized by means of conventional techniques. Activity and stability of these iron-containing samples has been tested in the catalytic wet peroxide oxidation (CWPO) of phenolic aqueous solutions. The crystallization mechanism involves a partial dissolution of the initial xerogel to yield an amorphous material. Nucleation and growth of the MFI phase is effected by reorganisation of the amorphous phase, although crystal growth also involves the incorporation of iron and silicon species during the last stage of the crystallization. A highly crystalline Fe-silicalite material is obtained after 3 h of synthesis at 170 degreesC. Spectroscopic studies reveal that iron species are in framework positions (isomorphously substituted) in this highly crystalline material. In addition, the environment of Fe atoms as well as textural properties of the samples is dramatically modified along the crystallization affecting significantly to their catalytic activity and stability in CWPO processes. (C) 2004 Elsevier Inc. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据