Photocatalytic Degradation of Synthetic Textile Effluent by Modified Sol-Gel, Synthesized Mobilized and Immobilized TiO2, and Ag-doped TiO2

Abstract

Advanced oxidation processes (AOPs) have proven to be very effective for treating various hazardous organic pollutants in water. The present study uses a double-walled horizontal glass reactor (DHGR) to investigate heterogeneous UV/TiO 2 (titanium dioxide) and UV/Ag-TiO 2 (mobilized and immobilized) photocatalytic degradation of synthetic textile effluent (Remazol Red RGB) with UV (400W). The textile effluent was characterized in terms of pH, chemical oxygen demand (COD), and degree of decolorization (at 519 nm) before and after treatment. Optimum degradation results were obtained at pH3. We also found that with different catalysts and catalyst doses, the rate of degradation rises up to a maximum "critical" value. The electron scavenger was Ag-led to a faster degradation of synthetic textile effluent in the photocatalytic system. The photocatalytic degradation proved to be dependent on the effluents' initial COD, catalyst dose, catalyst form, and pH of the medium. Results reveled that among different forms of catalysts, Ag-TiO 2 (Mesh) and TiO 2 (0.5 g) showed better COD percentage and ABS percentage removal at pH3 with initial concentrations of synthetic effluent 560mg/l under UV(400W) irradiation.