催化学报

催化学报 ›› 2010, Vol. 31 ›› Issue (1): 84-89.

• 研究论文 • 上一篇    下一篇

介孔纳米 MoPO-AlPO4 的制备及其对异丁烯选择氧化的催化性能

王希涛, 毕超, 钟顺和, 肖秀芬   

  1. 天津大学化工学院天津市应用催化科学与工程重点实验室, 天津 300072
  • 收稿日期:2010-01-25 出版日期:2010-01-25 发布日期:2010-01-25

Preparation of Mesoporous Nanosized MoPO-AlPO4 and Its Catalytic Per-formance for Selective Oxidation of Isobutene

WANG Xitao, BI Chao, ZHONG Shunhe*, XIAO Xiufen   

  1. Tianjin Key Laboratory of Applied Catalysis Science and Technology, College of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China
  • Received:2010-01-25 Online:2010-01-25 Published:2010-01-25

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摘要： 分别采用溶胶-凝胶法和等体积浸渍法制备了 MoPO-AlPO4 催化剂, 考察了钼物种存在状态对催化剂晶格氧活性以及异丁烯选择氧化反应性能的影响. N2 吸附-脱附、X 射线衍射、高分辨透射电镜、X 射线光电子能谱、傅里叶变换红外光谱、程序升温还原和微反实验结果表明, 与浸渍法制备的催化剂相比, 溶胶-凝胶法制备的 MoPO-AlPO4 催化剂为介孔纳米材料, 其比表面积和孔数量均有较大程度的提高. 在浸渍法制备的催化剂中, 钼物种以四面体 MoO42− 和八表面体 MoO66− 形式存在; 而在溶胶-凝胶法制备的催化剂中钼物种主要以四面体 MoO42− 的形式存在, 并有部分钼物种嵌入到了 AlPO4 骨架中. 钼物种的种类对异丁烯选择氧化反应的活性和选择性有较大影响, 溶胶-凝胶法制备的催化剂由于嵌入 AlPO4 骨架中钼物种的存在, 异丁烯选择氧化反应性能得到较大提高.

关键词: 溶胶-凝胶法, 浸渍法, 介孔磷酸铝, 异丁烯, 选择氧化

Abstract: MoPO-AlPO4 catalysts were prepared by sol-gel and impregnation methods. The effects of Mo species on crystal lattice oxygen activity and catalytic performance of MoPO-AlPO4 for selective oxidation of isobutene were investigated. The catalysts were characterized by N2 adsorption-desorption, X-ray diffraction, high resolution transmission electron microscopy, Fourier transform infrared spectroscopy, and temperature-programmed reduction. The results showed that the MoPO-AlPO4 prepared by the sol-gel method existed as mesostructured nanoparticles with larger surface area and more pores than the corresponding MoPO-AlPO4 prepared by the impregnation. Mo species appeared in tetrahedral coordination in the sample prepared by the sol-gel method and in both tetrahedral and octahedral coordinations in the sample prepared by impregnation. This indicated that the sample prepared by the sol-gel method had better dispersion of Mo species than that prepared by impregnation. The Mo species incorporated-mesoporous AlPO4 obviously improved the catalytic performance of MoPO-AlPO4 for selective oxidation of isobutene.

Key words: sol-gel method, impregnation, mesoporous aluminophosphate, isobutene, selective oxidation