Influence of Titanium Dioxide Preparation Method on Photocatalytic Degradation of Organic Dyes

Titanium catalysts (TO2) were synthesized by three different methods. Their photocatalytic activity was validated through photodegradation of Reactive Red 45 (RR45) azo dye and Acid Blue 25 (AB25) anthraquinone dye in an aqueous solution under UV irradiation. Ti[O.sub.2] photocatalysts were characterized by FTIR, XRD and SEM. Photosensitivity and Ti[O.sub.2] activity range were characterized by UV/Vis spectroscopy. Photocatalytic validation has been made by way of determining the degree of RR45 and AB25 removal. TOC was determined as a measure of the mineralization of RR45 and AB25 by photocatalysis. The stability of Ti[O.sub.2] catalysts and a possibility of using them in consecutive photocatalysis cycles have also been studied. The results show that the photocatalytic efficiency depends on the crystal structure of Ti[O.sub.2]. The size of crystallites depends on synthesis conditions. From the results of photocatalytic efficiency it is concluded that the chemical interaction between a catalyst and a dye strongly depends on the dye chemical structure. Keywords: titanium dioxide, photocatalysis, organic dyes, wastewater treatment.