TiO2 mediated photocatalytic degradation studies of Reactive Red 198 by UV irradiation

Evaluation on the Photocatalytic Degradation Activity of Reactive Blue 4 using Pure Anatase Nano-TiO2

“…Therefore, the higher the initial concentrations of RB4 dye, the lower the photodegradation efficiency. This result is in agreement with the findings reported in the literature using a different type of TiO 2 (Chakrabarti & Dutta 2004;Kaur & Singh 2008;Neppolian et al 2002a). The increase in dye concentration reduces the number of photons penetrating the solution because they are absorbed before reaching the catalyst.…”

“…Full degradation was successfully achieved when 1 g/L of TiO 2 was applied. This result is in good agreement with others (Kaur & Singh 2008;Neppolian et al 2002a Carp et al (2004), light scattering will increase the opacity of the solution, reducing the light penetration and the degradation efficiency when too much catalyst is added. However, this phenomenon was not detected in this experiment.…”

Synthesis and application of multiple rods gold–zinc oxide nanostructures in the photocatalytic degradation of methyl orange

“…The data obtained showed that E% values increase with the increase in the amount of catalyst up to about 0.10 g L -1 (100 % decolorization and 94.9 % degradation after 140 min UV ; Au-ZnO, 10.0 mg and pH 6.5 irradiation) and then decrease marginally with further increase in the amount of the catalyst. Increase in the E% values with increase in the amount of catalyst can be rationalized in terms of the availability of active sites on the Au-ZnO surface, and also the number of dye molecules adsorbed (Sun et al 2006;Kaur and Singh 2007). However, increase in the amount of catalyst further than 0.10 g L -1 has a little negative effect on the decolorization or degradation of MO.…”

Photocatalytic degradation of Vat Yellow 4 using UV/TiO2

“…Above a certain level, since the dye concentration is kept constant the number of substrate molecules is not sufficient to fill the surface active sites of TiO 2 and hence further addition of catalyst does not lead to the enhancement of the degradation rate. The slight decrease in degradation rate at higher concentrations of the catalyst may also be due to the aggregation of TiO 2 particles at higher concentrations causing decrease in the number of surface active sites and also due to the increase in opacity and light scattering of TiO 2 particles (Kaur and Singh, 2007). Toor et al (2006) reported the optimum catalyst concentration for the degradation of Direct yellow dye to be 2.0 g/l.…”