Degradation Of P-Chloroaniline In Aqueous Solution With Advanced Oxidation Technology Based On Pyrite Activated Persulfate Under Aerobic Conditions

p-Chloroaniline is a common refractory organic pollutant in the environment. PCA has a wide range of applications in the field of chemical pesticides, pharmaceuticals, dyes and so on. So researches on methods and ways to degrade PCA is one of the hot issues in pollution control. Persulfate activation with SO4?- produced is a rising advanced oxidation technology in recent years, which has the advantages of high oxidation ability and a wide operating p H range, and the activation process is crucial on applying the technology successfully to practice. In this paper, researches on persulfate activation and degradation of PCA in aqueous solution based on pyrite activated persulfate under aerobic conditions has been illustrated, then further explored the mechanism of persulfate activation by pyrite and the effect on degradation when weak magnetic field and ferrous chelating agents are introduced. The main contents and results are as follows:(1) Persulfate activation by pyrite under aerobic condition and degradation of PCA have been studied, which investigated the effect of dissolved oxygen on PCA degradation under room temperature and neutral condition by comparing the PCA degradation rate when blowing air, nitrogen or neither of them into the solution. The results show that the PCA degradation process favors aerobic conditions. Under aerobic condition, the superoxide radicals(O2?-) which react with persulfate(S2O82-) to produce sulfate free radical(SO4?-) in subsequent process have been generated in the pyrite/persulfate systems, which contributes to the PCA degradation.(2) Persulfate activation by pyrite under aerobic condition and kinetics of degradation PCA have been studied, which investigated effect of pyrite dosage, initial p H, sodium persulfate concentration and reaction temperature on PCA degradation. The PCA degradation rate increased with the increase of Fe S2 content, PS initial concentration and temperature, but decreased when p H increased.(3) Persulfate activation by pyrite under aerobic condition and degradation of PCA have been studied when a weak magnetic field was introduced. The results show that the PCA degradation is promoted with the weak magnetic field.(4) Persulfate activation by pyrite under aerobic condition and degradation of PCA have been studied, which investigated effect of oxalic acid, citric acid and Ethylene Diamine Tetraacetic Acid(EDTA) on PCA degradation. The results find that oxalic acid, citric acid and EDTA promoted PCA degradation at concentrations ranging from 0.05mmol?L-1 to 2.5 mmol?L-1.