Degradation of reactive orange 1 in a semi-batch photocatalytic reactor (UV/ZnO-Ag)

In this study, ZnO nanoparticles modified by Ag were synthesized using microwave assisted solution combustion method. The structural, optical and morphologies of the samples were characterized by scanning electron microscope (SEM) and UV-Vis. SEM images showed that the Ag/ZnO photocatalysts consist of cluster of ultrafine particles which are highly porous. The photocatalytic activity of the Ag/ZnO was investigated by photodegradation of Reactive Orange 1 under UV illumination in a semi-batch reactor. This experiment showed that Ag-doped ZnO has much more photocatalytic property than ZnO synthesized by the same method. The effects of operating parameters such as pH, catalyst amount and dye concentration were investigated. Studies revealed that pH=6.4(Normal) and catalyst amount= 0.06 g are optimum condition for decolorization of 20 mg/l Reactive Orange 1 solution. Kinetic studies indicated that the decolorization process follow first order kinetics.