Study On Sulfite Related Advanced Oxidation System And Its Treatment Performance To Wastewater

Advanced Oxidation Processes?AOPs?based on the generation of sulfate radicals(SO₄^·-)has advantages of high reactive speed,simply reaction conditions and long duration in the environment.So it has good development in the wastewater treatment.And now most studies generate sulfate radicals by using activated persulfate,a few reports on activated sulfite.In this study,the properties and mechanism were investigated when sulfites that are activated by transition metal ions(such as Fe²⁺,Cr⁶⁺)in the presence of oxygen for treating industrial wastewater.In this report,we studied the degradation of several typical pollutions by transition metal ion activated sulfites through the construction of Fe²⁺/SO₃^2-and Cr⁶⁺/SO₃^2-.Firstly,we studied the effects of different factors?such as concentration,pH,common metal ions?on the degradation of the system,and the types of free radicals were confirmed by scavenger experiments.The results show that both systems could achieve a good contaminants degradation performance,and its degradation rate was more than 70%within20 minutes,and the oxygen is consumed in this process.The reaction is effective under wide range pH,the best pH value is 3⁴,The Mn²⁺and Fe³⁺in system have inhibitory effect on the degradation of the system,while Al³⁺has no remarkable effect.The results of scavenger experiments show that SO₄^·-was the main reactive oxygen species for contaminant degradation.This study provided some theoretical guidance for the transition metal ions activated sulfite in industrial wastewater treatment.