UV irradiation catalyzed persulfate advanced oxidation process for decolorization of Acid Blue 113 wastewater

Abstract

A UV/persulfate advanced oxidation process was proposed to decolorize and mineralize a synthesized Acid Blue 113 (AB113) dyeing wastewater. Various operating parameters which affected the removal efficiencies of dye and total organic carbon (TOC) such as reaction time, persulfate dosage, initial dye concentration, initial pH, and UV intensity were studied. Results presented effective removal of AB113 azo dye by UV/persulfate process based on both color and TOC indicators. However, reaction with either UV irradiation alone or persulfate alone can reach low-removal efficiency of AB113. In UV/persulfate process, the higher the persulfate dosage applied, the higher the color and TOC removal efficiencies can be obtained up to 6.3 mM persulfate concentration. The color removal efficiency and reaction rate constant decreased with increase in the initial dye concentration. The initial pH was shown no significant effect on removal efficiency. UV intensity affected AB113 removal efficiency significantly when the persulfate dosage was as low as 1.05 mM. Results of UV-Visible spectrophotometry indicated the diminishing of chromophore group of AB113 at 566 nm and naphthalene rings at 272 nm.

Keywords:

• Persulfate
• UV
• Decolorization
• Mineralization
• Azo dye

Acknowledgment

The authors appreciate the research funding granted by the Taiwan National Science Foundation (NSC 101-2221-E-241-004-MY3).

Notes

Presented at the 6th International Conference on the “Challenges in Environmental Science and Engineering” (CESE-2013), 29 October–2 November 2013, Daegu, Korea