Removal of Acid Blue 29 in aqueous solution by Fenton and Fenton-like processes

Abstract

The decoloration and mineralization of the azo dye, Acid Blue 29 (AB 29) in aqueous solution was investigated in the presence and absence of air by Fenton and Fenton-like processes using hydrogen peroxide (HP) and sodium persulfate (SPS), respectively, as oxidants. The effect of various operational parameters and presence of , , , and ions on the decoloration was examined. Higher decoloration was observed at pH 3 and 5 in both the cases. On the basis of mineralization efficiency (34.1 and 28.5%, respectively, with HP and SPS in 180 min), it was concluded that HP is a better oxidant than that of SPS. The decoloration in the absence of air is decreased until a certain time period, beyond which it increases and becomes same as that in the presence of air. This is explained on the basis of in situ generation of HP and peroxyl radicals. Although all ions under study inhibit decoloration significantly, the inhibition efficiency of is less than that of others.

Keywords:

• Acid Blue 29
• Decoloration
• Mineralization
• Hydroxyl radical
• Inorganic ions
• Peroxyl radical

Acknowledgment

The authors gratefully acknowledge the University Grants Commission, Govt. of India for financial assistance (F. 40-76/2011 (SR)).