Photocatalytic Activity of Transition Metal Ion Doped Titania for Amaranth Dye Degradation

Abstract

nanosized titania catalyst and transition metal doped titania photocatalysts such as TiO2/Ag, TiO2/Cu and TiO2/Ag/Cu were used for photocatalytic degradation of Amaranth. Doping of titania was done with impregnation method. Photocatalytic activity was checked in terms of percentages of decolorization, COD removal and TOC removal. It was found that TiO2/Ag/Cu doped photocatalyst was more effective for Amaranth dye degradation under feasible treatment conditions. For decolorization, Amaranth took irradiation time of 210 min with UV/H2O2 but it took only 60 min with TiO2/Ag/Cu doped photocatalyst. Only 29% COD and 49% TOC removal were achieved with homogeneous photodegradation, whereas with TiO2/Ag/Cu heterogeneous photodegradation, 100% COD and 98% TOC removal was achieved in 9h for 50 ppm aqueous Amaranth solution. The relative electrical energy consumption per order of magnitude for photocatalytic degradation of Amaranth was considerably lower with TiO2/Ag/Cu catalyst than that with UV/H2O2 and other combinations of doped photocatalyst. The photocatalysts were characterized using XRD and TEM analysis.