物理化学学报 >> 1994, Vol. 10 >> Issue (06): 521-525.doi: 10.3866/PKU.WHXB19940608

研究论文 上一篇    下一篇

12-钼磷酸与γ-Al2O3载体的相互作用

郑寿荣, 戚海华, 颜其洁, 傅献彩   

  1. 南京大学化学系,南京 210008
  • 收稿日期:1993-02-19 修回日期:1993-05-19 发布日期:1994-06-15
  • 通讯作者: 颜其洁

A Study of the Interaction Between 12-Molybdophosphoric Acid and γ-Alumina

Zheng Shou-Rong, Qi Hai-Hua, Yan Qi-Jie, Fu Xian-Cai   

  1. Department of Chemistry, Nanjing University, Nanjing 210008
  • Received:1993-02-19 Revised:1993-05-19 Published:1994-06-15
  • Contact: Yan Qi-Jie

摘要:

应用酸碱滴定、X射线衍射(XRD)、激光拉曼(LRS)和顺磁共振(EPR)等方法研究了磷钼酸(PMo_(12))与γ-Al_2O_3载体间的相互作用.结果表明,PMo_(12)在γ-Al_2O_3上随负载量增加出现三种不同的分散状态,据此提出了PMo_(12)在γ-Al_2O_3上的铺展模型.

关键词: 12-钼磷酸, γ-Al2O3, 铺展, 相互作用

Abstract:

12-moybdophosphoric acid (PMo_(12)) supported on γ-alumina has been studied by XRD, LRS EPR and titration methods.
The results reveal that as PMo_(12) loading is lower or equal to the monolayer coverage, there is a strong interaction between PMo_(12) and γ-alumina, PMo_(12) is adsorbed by γ-alumina irreversibly and a tetrahedral coordinatha Mo-O-Al species is observed.
Beyond monolayer coverage, the PMo_(12) is dispersed on γ-alumina as primary structure, and a secondary structure PMo_(12) is observed at more higher loading. The EPR results show that the stability of the supported PMo_(12) is lower than that of the unsupported PMo_(12) and the stability of PMo_(12) in the above three diffrent states is not the same. A model of PMo_(12) dispersed on γ-alumina is suggested.

Key words: 12-molybdophosphoric acid, γ-alumina, Dispersion, Interaction