Study On Activated Sodium Persulfate Advanced Oxidation Technology For Degradation Of Benzenoid Organic Pollutant

Environmental pollution accidents of benzenoid organics caused the disastrous impact on human health and the environment.Advanced oxidation technology can oxide and degrade benzenoid organics fast and efficiently.It also can be treated as a security measures for benzenoid organics and take response measures of source control in leakage immediately after accident.It chose aniline and 4-chlorophenol as particular pollutants.They were oxidated and degraded by different activation of Na₂S₂O₈ and the mechanism analysis was also studied.This dissertation studied initial aniline concentration,initial pH and the influence of different buffer system for Na₂S₂O₈ oxidation of aniline.Initial aniline concentration and initial pH was less affected on the oxidation of aniline but it had a greater influence in different buffer system.Under the condition?pH=7,3.0 g/L Na₂S₂O₈ and 100 mg/L aniline?,the oxidation rate reached up to 98.03%after 6 h in phosphate buffer solution.The experiment of methanol and tert-butanol quenching free radicals and the EPR test showed that the effect of·OH?SO₄^·-and O₂^·-was very small in the aniline oxidation;The comparison of different buffer solution showed that the phosphate anion may react with Na₂S₂O₈ and generate H₂PO₅^-.H₂PO₅^-played an important role in the reaction and made aniline oxidation fast.Aniline reaction product was test by fourier transform infrared spectroscopy detection and proved that there was aniline black in oxidation product.This dissertation investigated the degradation process of 4-chlorinephenol with catalyst CuFe₂O₄-Fe₃O₄ composite for the activation of persulfate.It investigated the amount of catalyst,4-chlorinephenol,Na₂S₂O₈ and initial pH effects on 4-chlorinephenol degradation.Experimental results showed that the degradation rate of 100 mg/L 4-chlorinephenol was 96.35%after 120 min treatment under the conditions?initial pH=11,2.0 g/L Na₂S₂O₈ and 1.0 g/L CuFe₂O₄-Fe₃O₄?and the TOC removal rate reached 93.4%after 240 min.Methanol and tert-butanol quenching experiments proved that the SO₄^·-and·OH were involved in the reaction and SO₄^·-played a dominant role with the assistance of·OH.The XPS of metal ion was detected before and after the reaction.It genenrated Fe²⁺and Cu²⁺in catalyst during the reaction.They were oxidated to Fe³⁺and Cu³⁺by SO₄^·-,respectively;The reaction between Cu³⁺and Fe²⁺promoted the circulation of reaction system.In conclusion,the dissertation found a new system?Na₂S₂O₈/phosphate buffer?which can effectively oxidize aniline and a new catalyst CuFe₂O₄-Fe₃O₄ composite which can degrade 4-chlorophenol fast.It achieved the the purpose of the degradation of benzenoid organics by Na₂S₂O₈ advanced oxidation technology.It was of great significance to deal with organic pollutants like benzene spill.