Degradation Investigation of Cobalt Tetraferrate/peracetic Acid Synergistic System to Acid Red B: an Effective Strategy for Treating Azo Dye Containing Wastewater

Abstract

The advanced peracetic acid (PAA) oxidation technology has a wide application prospect in the field of wastewater treatment for its high efficiency, environmental protection and wide application. In this work, cobalt tetraferrote (CoFe₂O₄) was used to activate PAA to degrade acid red B. The effects of CoFe₂O₄ catalyst dosage, PAA concentration, initial pH value and anion on the decolorization efficiency of acid red B were investigated by intermittent single factor experiments. The optimal reaction conditions for the degradation of 0.1 mM acid red B in the CoFe₂O₄/PAA system were as follows: catalyst dosage of 0.008 g, PAA concentration of 1 mM, and initial pH = 7. After 30 min of reaction, the degradation rate of acid red B reached was as high as 99.5%. The coexistence of CoFe₂O₄/PAA with low concentrations of anions and humic acid (HA) had negligible effects on the catalysis of acid red B, while the coexistence with higher concentrations of HCO₃⁻, H₂PO₄⁻ and HA inhibited the degradation behaviors. Quenching experiments confirmed that there were a large amount of R-O• and a small amount of •OH in the CoFe₂O₄/PAA system, and ¹O₂ played an important role in the degradation process. After 6 cycles, the catalytic performance of CoFe₂O₄ remained above 98.6%, showing stable catalytic performance, which were also confirmed by FTIR and XPS. This work provided a new way for effectively treating azo dye containing waste water.