Fe(Ⅵ)氧化含氮杂环化合物路径及机理  

Oxidation of nitrogenous heterocyclic compounds with ferrate(VI):Pathway and degradation mechanism

作　　者：王嘉琪 张继红 李亚男[1] 纪伟 郭凯 张国凯 WANG Jiaqi;ZHANG Jihong;LI Yanan;JI Wei;GUO Kai;ZHANG Guokai(Department of Environmental Science and Engineering,Taiyuan University of Technology,Jinzhong 030600,China;CHINASEA GROUP Co.Ltd.,Taiyuan 030012,China)

机构地区：[1]太原理工大学环境科学与工程学院,山西晋中030600 [2]中海国亚环保工程有限公司,山西太原030012

出　　处：《高校化学工程学报》2023年第4期659-668,共10页Journal of Chemical Engineering of Chinese Universities

基　　金：山西省应用基础研究计划(20210302123121);自然资源部生态地球化学重点实验室开放基金(ZSDHJJ201804)。

摘　　要：为了明确高铁酸钾[Fe(Ⅵ)]氧化降解含氮杂环化合物(NHCs)(吲哚、喹啉、吡啶)的机理,采用高效液相色谱、荧光光谱、气相色谱-质谱等方法,考察不同因素对NHCs降解效果的影响,捕捉自由基、识别氧化产物并推测反应路径。结果表明,当温度25℃、吲哚与Fe(Ⅵ)的物质的量比为1:15、pH为7时,15 min内吲哚的去除率为77.91%,过程中高价态铁起主导作用;当喹啉与Fe(Ⅵ)的物质的量比为1:5、pH为5时,10min内喹啉降解率为81.16%,羟基自由基(HO·)起重要作用;当吡啶与Fe(Ⅵ)的物质的量比为1:3、pH为7时,5 min内吡啶去除率为36.89%,HO·起一定作用。Fe(Ⅵ)对3种NHCs有一定矿化效果。Fe(Ⅵ)降解NHCs的第一步均为羟基化产物的生成,随后经加成、脱氮、脱羰等反应实现氮杂环开环。In order to clarify the degradation mechanism of nitrogenous-heterocyclic compounds(NHCs),(indole(ID),quinoline(QL),and pyridine(PD))by potassium ferrate(Ⅵ),high performance liquid chromatography,fluorescence spectroscopy,gas chromatography-mass spectrometry and other characterization methods were used to study the effects of different factors on NHCs degradation.Free radicals were captured,the oxidation products of NHCs were identified and the main degradation pathways were discussed.The results show that when studied under conditions of temperature=25℃,molar ratio of indole to Fe(Ⅵ)=1:15 and pH=7,the degradation efficiency of indole is 77.91%after 15 minutes of oxidation.High-valent irons contribute more to the reaction.The removal rate of quinoline is 81.16%after 10 minutes of degradation,when the molar ratio of quinoline to Fe(Ⅵ)is 1:5 and pH is 5.HO·plays an important role during the oxidation.Pyridine is degraded by 36.89%after 5 minutes of reaction when the molar ratio of pyridine to Fe(Ⅵ)is 1:3 and pH is 7,and HO·plays limited effects in the process.Fe(Ⅵ)has certain mineralization effects on the three NHCs.The first step of NHCs degradation by Fe(Ⅵ)is the generation of hydroxylation products,followed by addition,denitrification,decarbonylation and other reactions to achieve the ring cleavage of nitrogen heterocyclics.

关 键 词：含氮杂环化合物(NHCs) 高铁酸钾 降解路径 自由基 矿化度 

分 类 号：X703[环境科学与工程—环境工程]