高等学校化学学报 ›› 1988, Vol. 9 ›› Issue (5): 475.

• 论文 • 上一篇    下一篇

H(M)ZSM-5杂原子分子筛的表面酸性和裂解催化行为

蒋大振, 肖丰收, 刘子阳, 徐如人   

  1. 吉林大学化学系
  • 收稿日期:1986-11-28 出版日期:1988-05-24 发布日期:1988-05-24
  • 通讯作者: 蒋大振

Surface Acidic and Catalytic Properties of H(M=Al, Ga, Fe)ZSM-5 Zeolite

Jiang Dazhen, Xiao Fengshou, Liu Ziyang, Xu Ruren   

  1. Department of Chemistry, Jijin University, Changchun
  • Received:1986-11-28 Online:1988-05-24 Published:1988-05-24

摘要: 用IR和ITPD技术研究了H(Al)ZSM-5、H(Ga)ZSM-5和H(Fe)ZSM-5杂原子分子筛的表面酸性。结果表明,这些分子筛表面既存在B酸中心,也存在L酸中心,但是就两种酸的表面浓度比值CL/CB而言,H(Ga)ZSM-5和H(Fe)ZSM-5要比H(Al)ZSM-5高得多。在十五烷裂解时,L酸中心起的作用可能更大。

关键词: 杂原子分子筛, 表面酸性, 裂化

Abstract: The surface acidities and catalytic activities of some trivalent heteroatom-containing H(M)ZSM-5 (M=A1, Ga, Fe) zeolite have been studied by means of TPD, IRand cracking of n-pentadecane.The results indicate that Bronsted and Lewis acidic sites are present in these zeolites but the CL/CB on the surfaces of H(Ga)ZSM-5 and H(Fe)ZSM-5 are more higher than that on the surface of H(Aj)ZSM-5. Besides, there exist in the order of the acidic strength H(Al)ZSM-5>H(Ga)ZSM-5>H(Fe)ZSM-5. Cracking activities have been found to be dependent on the heteroatom in the framework of the zeolite. The normalized activity and the selectivity of gas-oil increase in the order as H(Ga)ZSM-5>H(Al)ZSM-5>H(Fe)ZSM-5. These results suggest that the Lewis acidic site play an important part in the cracking of n-pentadecane.

Key words: Heteroatom zeolites, Surface acid, Cracking

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