Acta Phys. -Chim. Sin. ›› 1994, Vol. 10 ›› Issue (06): 521-525.doi: 10.3866/PKU.WHXB19940608

• ARTICLE • Previous Articles     Next Articles

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

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