Original Article | 2012, Vol.34, No.2, pp. 203-210
Photocatalytic decolorization of basic dye by TiO2 nanoparticle in photoreactor
Jutaporn Chanathaworn, Charun Bunyakan, Wisitsree Wiyaratn and Juntima Chungsiriporn
pp. 203 - 210
Abstract
Photocatalytic decolorization of rhodamine B (RB) and malachite green (MG) basic dyes in aqueous solution was evaluated using TiO2 powder as a semiconductor photocatalyst under UV black light irradiation. A 0.5 L batch photoreactor containing dyeing solution was installed in a stainless steel chamber with air cooling under irradiation. The TiO2 powder was characterized by XRD observation and it was shown that the nanoparticles could be identified as 73 nm anatase crystals. The effects of operational parameters such as light intensity (0-114 W/m2 ), initial dye concentration (10-30 mg/L), and TiO2 powder loading (0.5-1.5 g/L) on the decolorization of dye samples were examined. The photocatalytic decolorization rate depended on the pollutant’s structure, such that the MG dye could be removed faster than the RB dye. Decolorization efficiency (%) of the photocatalytic system increased with increasing TiO2 loading and light intensity; however, it decreased with increasing initial dye concentration. A loading of 1.5 g TiO2 /L, initial dye concentration of 20 mg/L, and light intensity of 114 W/m2 were found to yield the highest removal efficiency of dye solution based on time requirement. The kinetics are of first order and depend on the TiO2 powder loading and dye structure. The research had a perfect application foreground.
