Degradation of Azo Dyes by the Reduction and Oxidation with Nano Sized Zero Valented Iron
The objective of this study is to investigate the efficient method to maximize both color and TOC removal of the azo dye solution by reduction and oxidation with a laboratory synthesized nano-sized zero valent iron (nZVI). The decolorization efficiency increased with the decrease of pH and increase of zero valent iron dosage. The optimum dosage of nano-sized zero-valent iron was 20mg/L at pH 3. The surface normalized constant of nZVI was higher than those reported for the discoloring of azo dye with other ZVIs. The sequential dose of nZVI/H2O2 remove color and TOC more effectively than the simultaneous dose. Pre-reduction by nZVI could convert azo dye to products whose oxidation is more degradable and therefore enhances the removal efficiency.
Hyungsun Kim, Junichi Hojo and Soo Wohn Lee
B.H. Moon et al., "Degradation of Azo Dyes by the Reduction and Oxidation with Nano Sized Zero Valented Iron", Materials Science Forum, Vols. 544-545, pp. 705-708, 2007