催化学报

催化学报 ›› 2012, Vol. 33 ›› Issue (5): 898-904.DOI: 10.3724/SP.J.1088.2012.11201

• 研究论文 • 上一篇    

杂原子 Sn-β 分子筛的脱铝补位两步法制备、表征及其催化环己酮 Baeyer-Villiger 氧化性能

康自华, 刘海鸥, 张雄福*   

  1. 大连理工大学化工学院, 精细化工国家重点实验室, 辽宁大连 116024
  • 收稿日期:2011-12-02 修回日期:2012-03-06 出版日期:2012-05-09 发布日期:2012-05-09

Preparation and Characterization of Sn-β Zeolites by a Two-Step Postsynthesis Method and Their Catalytic Performance for Baeyer-Villiger Oxidation of Cyclohexanone

KANG Zihua, LIU Hai’ou, ZHANG Xiongfu*   

  1. State Key Laboratory of Fine Chemicals, School of Chemical Engineering, Dalian University of Technology, Dalian 116024, Liaoning, China
  • Received:2011-12-02 Revised:2012-03-06 Online:2012-05-09 Published:2012-05-09

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摘要： 采用酸处理 Al-β 脱铝以产生 T “空位”, 再高温焙烧插入 Sn, 即脱铝补位两步法制备了杂原子 Sn-β 分子筛. 考察了 β 沸石中 T “空位”数量、母体硅铝比和焙烧温度等因素对 Sn-β 分子筛形成与性能的影响, 并利用 X 射线衍射、红外光谱、紫外-可见光谱、扫描电镜、X 射线荧光光谱和电感耦合等离子体原子发射光谱等手段及环己酮 Baeyer-Villiger (B-V) 氧化反应, 对催化剂进行了表征和评价. 结果表明, 脱铝补位两步法可以制备 Sn-β 分子筛, 且 Sn 以四配位形式存在于分子筛骨架中, 在对环己酮 B-V 氧化反应中表现出较高的催化活性.

关键词: 锡, 杂原子 &beta, 沸石, 环己酮, Baeyer-Villiger 氧化反应, ε-己内酯

Abstract: A Sn-β zeolite was prepared by a two-step postsynthesis method. The procedure consists of first creating vacant T-sites with associated silanol groups by dealumination of Al-β zeolite with nitric acid and then impregnating the resulting Si-β zeolite with an aqueous solution of SnCl4·5H2O, followed by calcination at varying temperatures. The effects of the amount of vacant T-sites, SiO2/Al2O3 ratio of Al-β zeolite and calcination temperature on the formation of the Sn-β zeolites and their catalytic performances for Baeyer-Villiger oxidation of cyclohexanone were investigated. The structure of the catalysts was characterized by X-ray diffraction, infrared spectroscopy, UV-Vis spectrophotometry, scanning electron microscopy, X-ray fluorescence spectrometry and inductively coupled plasma atomic emission spectrometry. The results show that, the Sn-β zeolite has been synthesized using a two-step postsynthesis method, and the Sn4+ ions are incorporated in the framework of the zeolite in a tetrahedral environment. The synthesized Sn-β zeolite shows impressive catalytic performance in Baeyer-Villiger oxidation of cyclohexanone using hydrogen peroxide as an oxidant.

Key words: tin, heteroatom zeolite β, cyclohexanone, Baeyer-Villiger oxidation, ε-caprolactone