| 초록 |
Titanium dioxide(TiO2) photocatalysts have attracted great attention as a material for photocatalytic sterilization in the environmental industry. When TiO2 is irradiated with near-UV lights, it exhibits strong bactericidal activity. In addition, TiO2 is used for various purposes due to its high stability and strong oxidization capacity. The objective of this study is to evaluate the bactericidal effect in the presence of TiO2 on selected bacteria in the waste water including pathogenic waste water from hospital. Response surface methodology(Box-Behnken design) was applied to investigate the effects of principal parameters such as TiO2 concentration, UV illumination time, temperature, and pH on cell sterilization. It was found that TiO2/UV has stronger anti-bacterial capability compared to dark condition or UV-A illumination. The sterilization rate of pathogenic bacteria increased with TiO2 concentration, and reached the maximum at 1g/ℓ of TiO2 concentration. The sterilization ratio (%) of pathogenic bacteria was about 70% at the TiO2 concentration of 1g/ℓ with 30 min of UV illumination. The bactericidal effect increased, as the pH and temperature decreased, and the complete sterilization was reached in 2~3hrs of illumination. |
