• 关键词：无机阴离子  类-Fenton  过氧化氢  莠去津  苯酚

• 基金项目：国家自然科学基金资助项目(No.5047804950678104);广东省自然科学基金资助项目(No.04011215)

• 姜成春
• 深圳职业技术学院建筑与环境工程学院, 深圳 518055

• 庞素艳
• 哈尔滨工业大学深圳研究生院城市与土木工程学科部, 深圳 518055

• 江进
• 哈尔滨工业大学市政环境工程学院, 哈尔滨 150090

• 欧阳峰
• 哈尔滨工业大学深圳研究生院城市与土木工程学科部, 深圳 518055

• 马军
• 哈尔滨工业大学市政环境工程学院, 哈尔滨 150090

• 摘要：对比研究了4种常见无机阴离子(ClO₄^-、NO₃^-、Cl^-和SO₄^2-)对类-Fenton反应中H₂O₂分解和有机物(莠去津=2.1μmol·L^-1和苯酚=50μmol·L^-1)降解的影响.实验在pH=3.00±0.05(25℃)条件下完全混合反应器中进行.结果表明,在类-Fenton反应过程中,ClO₄^-和NO₃^-的存在对H₂O₂分解和有机物降解几乎没有影响;在不存在有机物条件下,Cl^-和SO₄^2-的加入使得H₂O₂分解速率显著降低,ClO₄^-≈NO₃^->Cl^->SO₄^2-;莠去津存在条件下,莠去津降解速率为ClO₄^-≈NO₃^->Cl^->SO₄^2-,而H₂O₂分解速率为ClO₄^-≈NO₃^-≈Cl^->SO₄^2-;苯酚存在条件下,苯酚和H₂O₂的降解速率为ClO₄^-≈NO₃^-≈SO₄^2->Cl^-.无机阴离子对类-Fenton反应的影响一方面是由于Cl^-和SO₄^2-与Fe³⁺发生络合反应,阻碍了Fe³⁺与H₂O₂络合物的形成,减少了·OH的产生;另一方面Cl^-和SO₄^2-消耗·OH,形成较低氧化活性的无机自由基(SO₄^·-和Cl₂^·-);同时,根据类-Fenton反应降解有机物的不同,无机阴离子对类-Fenton反应的影响也有所不同.

• Abstract：The effects of perchlorate,nitrate,chloride and sulfate ions on the rates of the decomposition of H₂O₂ and the oxidation of organic compounds([atrazine]₀=2.1 μmol·L^-1,[phenol]₀=50 μmol·L^-1) by Fenton-like processes were investigated.Experiments were conducted in a completely mixed reactor at pH=3.00±0.05(25℃).Data obtained from the Fenton-like experiments showed that the degradation rate of organics and H₂O₂ were not affected significantly in the presence of perchlorate and nitrate ions;whereas the presence of sulfate or chloride markedly decreased the rates of decomposition of H₂O₂ in the absence of organic solutes.The rates of reaction between Fe³⁺ and H₂O₂ followed the order ClO₄^-≈NO₃^->Cl^->SO₄^2-.The rates of depletion of atrazine followed the order ClO₄^-≈NO₃^->Cl^->SO₄^2- and the rates of decomposition of H₂O₂ in the presence of atrazine in aqueous solution were ClO₄^-≈NO₃^-≈Cl^->SO₄^2-.In the phenol system,the rates of degradation of phenol and H₂O₂ followed the order ClO₄^-≈NO₃^-≈SO₄^2->Cl^-.These inhibitory effects by inorganic anions are attributed to(i) the decrease of the rate of generation of hydroxyl radicals resulting from formation of complexes between Fe³⁺ and sulfate or chloride ions;(ii) formation of less reactive inorganic radicals(SO₄^·- and Cl₂^·-) resulting from competitive reactions between the hydroxyl radicals and sulfate or chloride ions.The impact of inorganic anions on Fenton-like reaction was also dependent on the characteristics of the model organic compounds in the system.

• Key words：inorganic anions  Fenton-like  hydrogen peroxide  atrazine  phenol

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