Application of catalytic ozonation in treatment of dye from aquatic solutions

Abstract

Decomposition of Basic Blue 9 (BB-9) in aqueous solution using ozonation and catalytic ozonation system (O3/granular activated carbon [GAC]) in the bench-scale experiment was investigated. The effect of ozone dose, pH, and GAC contents in removal of BB-9 and biodegradability of effluent such as Biochemical Oxygen Demand (BOD5); Chemical Oxygen Demand (COD), and BOD5/COD were studied. Results show that pH of solution and ozone concentration are significant factors on removal of BB-9; COD and BOD5. Kinetic studies of reactions indicated that reactions followed the first-order kinetics model. The application of GAC as catalyst, in mass concentration of 2 g/l, caused 48% increase in the degradation rate of BB-9. Ozonation process caused an increase in biodegradability of BB-9. However, catalytic ozonation did not have an effect on the biodegradability of the effluent. Acute toxicity tests with Daphnia magna show that this applied treatment method can significantly decrease toxicity of dye in aquatic solutions.