TiO2 phototcatalysts deposited on activated carbon (AC) were prepared by a dip-hydrothermal method using an aqueous solution of metatitanic acid as a precursor, and calcined in 300～800 ℃. The samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Raman spectrum and nitrogen adsorption. The photocatalytic activity of samples was evaluated by degradation of methyl orange (MO) as target pollutant. The results showed that uniformly dispersed TiO2 particles of anatase type were deposited on the activated carbon surface. TiO2/AC calcined at 600 ℃ exhibited the best performance. For the comparison, the same degradation procedure was carried out for two mixtures of commercial TiO2 (Degussa P25) with AC and synthetic TiO2 with AC. It was found that MO photocatalytic degradations were of apparent first order and TiO2/AC had higher photocatalytic efficiency than the two mixtures. The efficiency of TiO2/AC photocatalyst for MO degradation was hardly changed after 5-cycle use.

Key words: metatitanic acid, deposited TiO2, activated carbon support, photocatalysis