Catalytic Combustion Of Chlorobenzene On VO_x/TiO₂ Catalysts

Chlorobenzene is harmful to the environment and catalytic combustion shows its efficiency in the disposal of chlorobenzene. VOx/TiO2 has been widely studied in various ways due to its excellent catalytic performance. In this dissertation, the effect of preparation conditions on the catalytic activity of VOx/TiO2 was investigated by the adjustment of the loading of VOx, the resource of TiO2 and calcination temperature. The results of characterization of XRD, BET and XPS and the catalytic combustion of chlorobenzene indicated that VOx/Ti02 catalyst, which prepared with 3% VOx and TiO2, from hydrolysis of TiCl4 or nano-TiO2, presented the best activity. The BET surface area of the catalysts and the amount of oxalate in the preparation process did not show significant influence on the activity. The VOx/TiO2 catalyst was steable in the combustion of chlorbenze.The addition of K, Ba, La, Ce, Mn, Cu, Zr to VOx/Ti02 catalysts reduced the catalytic activity in chlorobenze combustion. K or Ba-doped catalyst presented the lowest activity owing to the strong basicity of K and Ba, while the activity decreased with the increase of the amount of La addition, while suggested the surface acidity played an important role in chlorobenzene combustion. The doping of Ce, Ze, Cu and Mn had the slight decrease of the activity of VOx/TiO2 catalyst, revealing that the synergism between dopant and VOX did not exist and VOx were better catalytic center in chlorobenze combustion than other elements studied.