Enhancement of decolorization rate and COD removal from dyes containing wastewater by the addition of hydrogen peroxide under solar photocatalytic oxidation

Photocatalytic Degradation of Textile Dye and Wastewater

“…As the catalyst concentration increases, the number of photons absorbed and the number of dye molecules adsorbed are increased owing to an increase in the number of catalyst particles. The density of particles in the area of illumination also increases, and so the degradation rate is enhanced (Akbal 2005;Ghaly et al 2007). …”

Enhancement of olive mill wastewater biodegradation by homogeneous and heterogeneous photocatalytic oxidation

“…As expected, the removals of TOC and COD were found to increase with the increasing concentration of TiO 2 and approaching a limiting value at high concentration. The limiting value (2 g/L) mainly results from the following two factors: (a) aggregation of TiO 2 particles at high concentrations, causing a decrease in the number of active surface sites, and (b) increase in opacity and high scattering of TiO 2 particles at high concentrations leading to a decrease in the passage of irradiation through the sample [40][41][42].…”

“…In such a condition, part of the catalyst surface probably became unavailable for photon absorption and dye adsorption, thus bringing little stimulation to the catalytic reaction and may be the other reasons for the decrease in both TOC and COD % removals [41][42][43]. Hence 2 g/L was used as the optimum catalyst dosage for the photocatalytic reaction.…”

Studies on UV/NaOCl/TiO2/Sep photocatalysed degradation of Reactive Red 195

“…The pH of the solution in the photocatalytic reactions taking place on the particulate surfaces is an important parameter [11]. Depending on the initial pH, removal of colour, COD and changes taking place in speed constants are presented in Fig.…”