(169b) Degradation of Polycyclic Aromatic Hydrocarbons in Water/methanol Solutions with Nanoparticle Photocatalysts Based on Silver Doped TiO2

Photodegradation of polycyclic aromatic hydrocarbons (PAHs) in water/methanol solutions was investigated in this study. Both direct photodegradation and photocatalytic degradation of phenanthrene, fluorene, and benzo[a]pyrene dissolved in aqueous/methanol solutions (20% methanol in water) were performed in a thin film photoreactor. PAHs were irradiated with a 5W low-pressure mercury lamp that was placed in a quartz immersion well to filter out high-energy UV bands (γ<290nm). The silver loaded on titanium dioxide (Ag/TiO₂) 1.0% (wt.%) silver was loaded on surface of the commercial anatase TiO₂ powder from aqueous AgNO₃ solution. The photocatalysts were characterized by FTIR, TEM, XRD and XPS measurements. Ag-TiO₂ was found to be nanometer particles mainly existing with anatase crystals and Ag was mostly in zero valence state. The results indicated that silver loaded on titanium dioxide (Ag/TiO₂) can improve rapidly the photodegradation rates of these PAHs in aqueous/methanol solutions, compared to direct photodegradation. Degradation of PAHs with nanoparticle photocatalyst Ag-TiO₂ may be one of the promising technologies in the field of water treatment.