A Study on Factors Affecting Photocatalytic Degradation of Azo Dyes Using Titanium Dioxide Nanoparticles in Aqueous Solution

Between semiconductor oxides, titanium dioxide has been used as the most suitable material for environmental photocatalytic applications has been applied due to the high chemical stability, reasonable prices and lack of toxicity. Extensive research has shown that the anatase crystalline form shows more photocatalytic activity in comparison with the rutile form. Photocatalytic destruction efficiency can vary depending on the used light that is ultraviolet light or sunlight. Also other parameters, such as pH, the amount of photocatalyst, initial dye concentrations, presence of oxidant, light intensity, time of radiation, presence of mineral ions and solvent can be effective on the destruction of azo dyes that will be investigated in this study. Results show that in the process of degradation of azo dyes, main intermediate compounds include hydroxylate derivatives, aromatic amines, phenolic compounds and organic acids. In this article the factors affecting the degradation of different azo dyes using titanium dioxide nanoparticles as a photocatalyst in aqueous solution under ultraviolet radiation and sunlight will be investigated.