Performance Of Stirred Slurry Photocatalytic Reactor In Azo Dye Degradation

Dye wastewater is recongnized as a kind of unmanageable industrial effluent, which can be ascribed to its large quantum, high concentration, complex component, dark chroma, high salinity, strong toxieity and difficulty by biochemical degradation. Currently, more and more researchers become interested in this issue. A stirred slurry photocatalytic reactor with effective volume5L was constructed and applied to study the photocatalytic degradation of reactive brilliant red X-3B, a typical azo dye. The adsorption behavior of X-3B on the TiO2surface and some operation factors such as TiO2dosage, stirring speed and air agitation, which impacted photocatalytic degradation rate of X-3B, were explored in detail.By analyzing the degradation kinetics of X-3B, the correlation between stirring intensity and initial react rate was set up. The experimental results showed that the adsorption behavior of X-3B on the TiO2fitted very well to the Langmuir and Freundlich model. Four50W ultraviolet lights were used as the irradiation source, in the condition of optimum catalyst loading of0.5g/L, the decolorization rate of reactive red X-3B was as high as99.35%after180min photocatalytic reaction time. The initial reaction rate increased with stirred Reynolds number at first and then went up to a stable value. The initial reaction rate can be improved significantly by adding aeration appropriately. It can be deduced that the transfer of oxygen in the reactor was a prominent factor to affect the initial react rate. Finally, compared with the1L reactor, photocatalytic reaction efficiency of the scale-up reactor was not significantly reduced.