| 引用本文: | 关英红,孙维敬,王盼盼.PMS/Fe0体系中自由基产率比及莠去津降解动力学[J].哈尔滨工业大学学报,2022,54(2):50.DOI:10.11918/202102008 |
| GUAN Yinghong,SUN Weijing,WANG Panpan.Radical production ratio and atrazine degradation kinetics in PMS/Fe0 system[J].Journal of Harbin Institute of Technology,2022,54(2):50.DOI:10.11918/202102008 |
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| 摘要: |
| 针对水体中存在的难降解农药莠去津（ATZ）污染问题,提出零价铁活化过氧单硫酸盐（PMS/Fe0）降解水中的ATZ,研究不同工艺参数（溶液pH、PMS投加量、Fe0投加量、ATZ初始浓度）条件下ATZ的降解动力学。采用硝基苯（NB）和ATZ竞争实验的方法,原位鉴定PMS/Fe0体系的自由基种类,并进一步基于稳态假设定量推导得到自由基产率比的公式。最后,研究了模拟地下水条件下PMS/Fe0对ATZ的降解规律。结果表明:ATZ降解的假一级速率常数（kobs）,随pH的增加而降低,随ATZ初始浓度的增加而降低,随Fe0投量增加而增加,随PMS的投量先增加后降低,在PMS投量为25 μmol/L时最大。NB和ATZ的竞争实验结果表明,PMS/Fe0体系中的活性物种为硫酸根自由基（SO-4·）和羟基自由基（·OH）,且两种自由基的产率比为10.5∶1。在模拟地下水条件下,Fe0和PMS的投量为0.25 g/L和25 μmol/L时,ATZ的降解率可达87%,说明模拟地下水水质背景下PMS/Fe0对ATZ有很好的降解效果。研究结论可对PMS/Fe0工艺修复受ATZ等农药污染地下水的工艺参数设计提供理论指导。 |
| 关键词: 零价铁 莠去津 过氧单硫酸 硫酸根自由基 羟基自由基 地下水 |
| DOI：10.11918/202102008 |
| 分类号:X523 |
| 文献标识码:A |
| 基金项目:黑龙江省普通本科高等学校青年创新人才培养计划(UNPYSCT-2018166) |
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| Radical production ratio and atrazine degradation kinetics in PMS/Fe0 system |
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GUAN Yinghong1,SUN Weijing1,WANG Panpan2
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(1.School of Water Conservancy and Civil Engineering, Northeast Agricultural University, Harbin 150030, China; 2.School of Environment, Harbin Institute of Technology, Harbin 150001, China)
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| Abstract: |
| In view of the frequent detection of atrazine (ATZ) in water body, which is a recalcitrant herbicide, zero-valent iron activated peroxymonosulfate (PMS/Fe0) was proposed to remove the ATZ in water. The effects of operation parameters (pH value, initial ATZ concentration, and PMS and Fe0 dosages) on ATZ degradation were investigated. Then the reactive species in PMS/Fe0 system were in-situ identified based on the competitive reactions of nitrobenzene (NB) and ATZ, and the formula for radical production ratio was derived under steady-state assumption. Finally, the degradation of ATZ by PMS/Fe0 was investigated under simulated groundwater condition. Results show that the pseudo-first order rate constant (kobs) of ATZ degradation decreased with increasing pH value and initial ATZ concentration, and increased with increasing Fe0 dosage. While it increased first and then decreased as the PMS dosage increased, reached the maximum at 25 μmol/L PMS. The competition experiment shows that sulfate radical (SO-4·) and hydroxyl radical (·OH) were reactive species in PMS/Fe0 system, and the production ratio of the two radicals was calculated to be 10.5∶1. ATZ degradation efficiency could reach 87% at 0.25 g/L Fe0 and 25 μmol/L PMS under simulated groundwater condition, indicating the prospective performance of PMS/Fe0 under groundwater conditions. The research results can provide theoretical reference for PMS/Fe0 applications in remediation of atrazine-polluted groundwater. |
| Key words: zero-valent iron atrazine peroxymonosulfate sulfate radical hydroxyl radical groundwater |
