能源化学(英文) ›› 2004, Vol. 13 ›› Issue (4): 238-243.

• Articles • 上一篇    下一篇

Gas Phase Selective Catalytic Oxidation of Toluene to Benzaldehyde on V2O5-Ag2O/Al2O3 Catalyst

Tonglai Zhang, Liqiu Mao, Weihua Liu   

  1. State Key Laboratory of Prevention and Control of Explosion Disasters, Beijing Institute of Technology,
  • 出版日期:2004-12-30 发布日期:2004-12-30

Gas Phase Selective Catalytic Oxidation of Toluene to Benzaldehyde on V2O5-Ag2O/Al2O3 Catalyst

Tonglai Zhang, Liqiu Mao, Weihua Liu   

  • Online:2004-12-30 Published:2004-12-30

摘要: Gas phase selective catalytic oxidation of toluene to benzaldehyde was studied on V2O5- Ag2O/γ-Al2O3 catalyst prepared by impregnation. The catalyst was characterized by XRD, XPS, TEM, and FT-IR. The catalytic results showed that toluene conversion and selectivity for benzaldehyde on catalyst sample No.4 (V/(V+Ag)=0.68) was higher than other catalysts with different V/Ag ratios. This was attributed to the higher surface area, larger pore volume and pore diameter of the catalyst sample No. 4 than the other catalysts. The XRD patterns recorded from the catalyst before and after the oxidation reaction revealed that the new phases were developed, and this suggested that silver had entered the vanadium lattice. XPS results showed that the vanadium on the surface of No.4 and No.5 sample was more than that in the bulk, thus forming a vanadium rich layer on the surface. It was noted that when the catalyst was doped by potassium promoter, the toluene conversion and selectivity for benzaldehyde were higher than those on the undoped catalyst. This was attributed to the disordered structure of V2O5 lattice of the K-doped catalyst and a better interfacial contact between the particles.

关键词: V2O5-AgO, gas phase, selective catalytic oxidation, toluene, benzaldehyde

Abstract: Gas phase selective catalytic oxidation of toluene to benzaldehyde was studied on V2O5- Ag2O/γ-Al2O3 catalyst prepared by impregnation. The catalyst was characterized by XRD, XPS, TEM, and FT-IR. The catalytic results showed that toluene conversion and selectivity for benzaldehyde on catalyst sample No.4 (V/(V+Ag)=0.68) was higher than other catalysts with different V/Ag ratios. This was attributed to the higher surface area, larger pore volume and pore diameter of the catalyst sample No. 4 than the other catalysts. The XRD patterns recorded from the catalyst before and after the oxidation reaction revealed that the new phases were developed, and this suggested that silver had entered the vanadium lattice. XPS results showed that the vanadium on the surface of No.4 and No.5 sample was more than that in the bulk, thus forming a vanadium rich layer on the surface. It was noted that when the catalyst was doped by potassium promoter, the toluene conversion and selectivity for benzaldehyde were higher than those on the undoped catalyst. This was attributed to the disordered structure of V2O5 lattice of the K-doped catalyst and a better interfacial contact between the particles.

Key words: V2O5-AgO, gas phase, selective catalytic oxidation, toluene, benzaldehyde