Photocatalytic Study of some Common Allergens and Harmful Ingredients used in Everyday Products

The photocatalytic degradation of allergens such as triclosan on various semiconductor photocatalysts like TiO2, ZnO, WO3, Ag/TiO2 and Pd/TiO2 and isothiazolin-3-ones on WO3 in aqueous suspensions under different illumination conditions has been investigated. The degradation of triclosan was monitored by TOC disappearance, carbon dioxide evolution and chloride ion formation. It is shown that TiO2 exhibited the best photocatalytic efficiency compared to the other catalysts studied. Silver loaded TiO2 performed better than PdO/ TiO2. The photocatalytic degradation of isothiazolin-3-ones on WO3 was followed by UV-Vis spectrophotometry, total organic carbon (TOC), Gas chromatography (GC), High Pressure Liquid Chromatography (HPLC) and Ion Chromatography techniques. The degradation reaction is fast under suntest and then UV lamp, when it is compared to fluorescent lamps. The reaction proceeds faster in the presence of O2 than in other atmospheric conditions such as air, H2O2. The photocatalytic activity of WO3 is compared with TiO2 and ZnO. This study proves the viability of photocatalytic degradation of triclosan and isothiazolin-3-ones in an aqueous medium.