Preparation of mesoporous V₂O₅/TiO₂ via spray pyrolysis and its application to the catalytic conversion of 1, 2-dichlorobenzene

Mesoporous V₂O₅/TiO₂ particles with a spherical shape were prepared via spray pyrolysis, using P123 as a structure directing agent, and applied to the catalytic oxidation of 1, 2-dichlorobenzene (DCB). The texture properties of the prepared V₂O₅/TiO₂ particles were monitored by changing the P123/Ti molar ratio from 0.03 to 0.07 and the vanadia content from 3 to 7wt%. All the prepared samples had mesopores, but without any pore ordering. The sample prepared with a P123/Ti=0.05 (molar ratio) had the largest surface area (142m²/g) and smallest pore size (6.6nm). The quantity of vanadia loading affected the texture properties as well as the crystallographic form of the V₂O₅/TiO₂ particles. The major crystal phases of mesoporous V₂O₅/TiO₂ particles were anatase, but 7-30% were formed in the rutile phase, which depended on the quantity of vanadia loading. However, the catalytic activity of V₂O₅/TiO₂ particles progressively increased with increasing quantity of vanadia loading. With 7wt% V₂O₅/TiO₂ particles, 94% decomposition of 1, 2-DCB was achieved at 400°C. The mesoporous V₂O₅/TiO₂ particles prepared via spray pyrolysis showed higher catalytic activity compared with that prepared via the conventional impregnation method, which was due to the high dispersion of vanadia on the surface of pores. From the results obtained, the mesoporous V₂O₅/TiO₂ particles prepared via spray pyrolysis were confirmed to have excellent activity for the oxidation of 1, 2-DCB, particularly at temperatures lower than 350°C.