物理化学学报 >> 1995, Vol. 11 >> Issue (05): 385-389.doi: 10.3866/PKU.WHXB19950501

通讯    下一篇

Si-VPI-5分子筛的多核固体NMR研究

邓风, 岳勇, 杜有如, 叶朝辉, 田文彤, 庞文琴   

  1. 中国科学院武汉物理研究所|波谱与原子分子物理国家重点实验室|武汉 430071|吉林大学化学系|长春 130023
  • 收稿日期:1995-01-23 修回日期:1995-03-06 发布日期:1995-05-15
  • 通讯作者: 杜有如

Multinuclear Solid-state NMR Study of Si-VPI-5 Molecular Sieve

Deng Feng, Yue Yong, Du You-Ru, Ye Zhao-Hui, Tian Wen-Tong, Pang Wen-Qin   

  1. Laboratory of Nuclear Magnetic Resonance and Atomic and Molecular Physics,Wuhan Institute of Physics,The Chinese Academy of Sciences,Wuhan 430071|Deparment of Chemistry, Jilin University, Changchun 130023
  • Received:1995-01-23 Revised:1995-03-06 Published:1995-05-15
  • Contact: Du You-Ru

关键词: 硅取代, VPI-5, 29Si NMR, 1H MAS NMR

Abstract:

Multinucleax solid-state NMR was employed to study the silicon-substituted molecular sieve Si-VPI-5. 29Si and 27Al NMR suggest that Si can be incorporated into the framework of VPI-5 and the substitution of two silicon atoms for an aluminium atom plus a phosphorus atom is predominant. Such substitution is limited in a certain domain of the crystal and "silicon rich" regions are thus generated. 1H MAS spectra reveal that a small amount of silicon atoms substitute phosphorus only and SiOHAl groups are formed, which provides the acidic source for the molecular sieves. Si-VPI-5 prepared with silica gel as the silicon source exhibits a higher content of SiOHAL groups than that prepared with (EtO)4Si.

Key words: Silicon substitution, VPI-5, 29Si NMR, 1H MAS NMR