Organic pollutants decomposition by TiO2 visible-light photocatalysis with H2O2 assistance

The effects of crystalline structure(Anatase and Rutile) and H2O2 addition on TiO2 visible-light photocatalysis were studied, which used reactive brilliant red X-3B and phenol as model pollutants. The results indicated that reactive brilliant red X-3B could be degradated by the two form TiO2(anatase or rutile) under visible-irradiation with the assistance of H2O2, however, when the surface sites of TiO2 photocatalysts were preeminently occupied by CO32-, photodecomposition could not be processed. Phenol could also be degradated by the two form TiO2 under visible-irradiation with the assistance of H2O2, rutile TiO2 exhibited a better photocatalytic activity, and its degradation ratio could be 80% after 120 min of reaction. The concentration of the ring intermediates detected during phenol decomposition was evidently higher when using rutile TiO2 as photocatalyst, and the presence of hydroxyl radical inhibitor(tert-butyl alcohol or methanol) had great effects on the degradation efficiency of rutile TiO2, but had less effects on anatase TiO2. The degradation of phenol occurred mainly in the solution when using rutile TiO2 as photocatalyst, and in contrast, the degradation occurred mainly at the TiO2 particles surface when using anatase TiO2 as photocatalyst. © (2013) Trans Tech Publications, Switzerland.