Abstract:
The photocatalytic decolorization of four commercial dyes with different structures and
different substitute groups has been investigated using pure TiO2 and TiO2 sol-gel as
photocatalysts in aqueous solution under solar radiation. Influence of different kinds of dye
and photocatalyst on photo-catalytic process was studied. Solution temperature and daily
photon flux during experiment was calculated. The result decolorization percentage of four
dyes was in the following order: reactive yellow > methylene blue > tubantin blue > tubantin
red; this is due to molecular structural difference among these four molecules of dyes. High
decolorization when used TiO2 sol-gel due to small particle size, small surface area and wide
energy gab. The daily photon flux average was nearly constant during the experiments, owing
to its large surface area pure TiO2 caused higher average solution temperature than caused by
TiO2 sol-gel when they are used as potocatalytic decolorizers.
