Study on degradation of dye organics by maleic acid activated persulfate

Abstract

In recent years, advanced oxidation technology based on sulfate radicals (SO4•-) has attracted attention in the field of water treatment due to its outstanding advantages of high efficiency and stability. However, the common activation methods of persulfate mostly focus on energy input and catalyst introduction, which have problems such as high application costs and difficulties in catalyst recovery, as to limit the application of this technology in practical water treatment processes. Studies have shown that using simple organic compounds as activators enriches the activation pathways of persulfate. In order to further extend the research idea, a system for activation of persulfate with simple organic substances maleic acid was constructed, and the potential of this system for degradation of dye pollutants was explored. The degradation performance of the pollutant was related to the initial concentration of maleic acid, the amount of persulfate dosing and the initial pH of the solution. The oxidation system produced a series of reactive oxidants dominated by ·OH, 1O2 and O2·-, supplemented by a small amount of SO4•-, which degraded the pollutants by the combined action of radical and nonradical reaction pathways. Meanwhile, the system demonstrated good anti-interference ability against actual environmental factors during the application.

Keywords

• maleic acid
• persulfate
• dye
• radical reaction
• nonradical reaction