硫酸根自由基氧化氮杂环化合物效能及机理分析

Study on the efficiency and mechanism of nitricheterocyclic compounds oxidation by sulfate radical

氮杂环化合物(NHCs)在焦化、造纸、制药等行业广泛存在,具有生物毒性。采用零价铁激活过硫酸盐产生硫酸根自由基(SO4^·-),氧化NHCs的典型有机物——吡啶、喹啉、吲哚,分析其脱除规律、影响因素和去除机理。结果表明,在相同浓度下氧化去除速率为吲哚>喹啉>吡啶,去除率分别为99%、68%、60.2%。采用分子轨道理论和Guassian09软件,用M06-2X/6-311+G(d,p)水平几何优化。pH较低时NHCs首先被质子化,轨道能级差降低,SO4^·-对其去除率提高。

Nitrogen heterocyclic compounds(NHCs),which have significant biological toxicity,are widely existed in wastewater and soil of coking,papermaking and pharmaceutical industries.Zero-valent iron is used to activate per-sulfate to produce sulfate radical(SO4^·-),and oxidize the typical organics of NHCs,such as pyridine,quinoline and indoles.The removal performance,influencing factors and removal mechanism are analyzed.The results show that the order of oxidation removal rate is indole>quinoline>pyridine at the same concentration,and the removal rates are 99%,68%and 60.2%,respectively.By means of M06-2x/6-311+G(d,p)horizontal geometric optimization and frequency analysis,the molecular orbital theory and Guassian09 are used to analyze.When pH is low,NHCs is protonated first,the orbital energy difference is reduced,and the removal rate of SO4^·-is increased.