Degradation of benzene on Zr-doped TiO sub(2) photocatalysts with a bimodal pore size distribution

Zr-doped TiO sub(2) was prepared from TiOSO sub(4) and ZrOCO sub(3) by a co-precipitation method using NH sub(3).H sub(2)O as the precipitation agent. The Zr-doped TiO sub(2) was characterized by X-ray diffraction (XRD), low temperature N sub(2) adsorption-desorption measurement, and UV-Vis diffuse reflectance spectroscopy technology. Appropriate amounts of ZrO sub(2) addition can greatly improve the TiO sub(2) microstructure properties and its photocatalytic activities. In addition, polyethylene glycol (PEG) was used as a surfactant for templating the pore structure of samples. A bimodal pore structure can be controlled using PEG6000 and PEG20000 surfactants simultaneously during the preparation. The rate constant of benzene degradation over the Zr-doped TiO sub(2) linearly decreases with the increase of photocatalytic reaction temperature and decreases in a polynomial relation with the benzene concentration. Moreover, it increases approximately linearly with the increase of the illumination intensity or area.