摘要
为探索厌氧条件下HA(腐殖酸)对HCB(六氯苯)降解的影响,通过构建ρ(HA)为0(HA_0)、120(HA_(120))及200(HA_(200))mg/L厌氧发酵体系,利用气相色谱-电子捕获检测器(GC-ECD)对ρ(HCB)及中间产物进行测定.结果表明:发酵系统运行72 h后,HA_0、HA_(120)、HA_(200)处理中HCB降解率分别为13.0%、16.5%和17.4%,表明HA可以促进HCB的降解,并且随ρ(HA)的增加,降解效果越好,但降解效率增幅降低.对HCB脱氯中间产物的分析发现,PeCB(五氯苯)、TeCB(四氯苯)、TCB(三氯苯)和DCB(二氯苯)均有检出;在发酵的前12 h,ρ(DCB)快速增加,发酵72 h后HA_0、HA_(120)、HA_(200)处理中ρ(DCB)分别为50.6、51.0和57.6μg/L,明显高于其他中间产物,表明DCB是HCB脱氯的限速中间体;对DCB进行同分异构体分析表明,DCB的同分异构体有1,2-DCB、1,3-DCB和1,4-DCB三种,发酵结束后HA0、HA120和HA200处理中ρ(1,4-DCB)最高,分别为22.0、17.2和18.7μg/L,1,4-DCB为HCB降解的主要中间产物.研究显示,通过调控厌氧发酵体系内HA的含量可达到强化HCB脱氯的目的.
In order to explore the effects of humic acid（ HA） on the degradation of hexachlorobenzene（ HCB） in anaerobic environment,an anaerobic fermentation system of HA concentration 0（ HA0）,120（ HA120） and 200（ HA200） mg/L was constructed,and a gas chromatography-electron capture detector（ GC-ECD） was used to measure the concentration of HCB and its degradation products. The results showed that the degradation rates of HCB in the HA0,HA120 and HA200systems were 13. 0%,16. 5% and 17. 4% respectively after 72 h fermentation. HA promotes the degradation of HCB under anaerobic fermentation conditions,and the degradation effect was better with the increasing of HA,but the degradation efficiency decreased. Along with the fermentation,the dechlorinating products of HCB were detected,and were shown to contain pentachlorobenzene（ Pe CB）,tetrachlorobenzene（ Te CB）,trichlorobenzene（ TCB） and dichlorobenzenc（ DCB）. DCB increased quickly during the beginning 12 h,and it was detected to be 50. 6,51. 0 and 57. 6 μg/L respectively in the HA0,HA120 and HA200systems after 72 h fermentation,which was significantly higher than other products. DCB was considered the dechlorination rate limiting intermediate product of HCB. Through isomers analysis of DCB,we found that 1,2-DCB,1,3-DCB and 1,4-DCB were detected. The result showed that the content of 1,4-DCB was highest,which was 22. 0,17. 2 and 18. 7 μg/L respectively in the HA0,HA120 and HA200 systems after the fermentation finished, and 1,4-DCB was regarded the main intermediate product in the degradation of HCB. Therefore,dechlorination of HCB can be regulated by HA during anaerobic digestion.
出处
《环境科学研究》
EI
CAS
CSSCI
CSCD
北大核心
2016年第6期870-876,共7页
Research of Environmental Sciences
基金
国家科技支撑计划项目(SQ2015BA1201473)
关键词
六氯苯
腐殖酸
厌氧降解
降解产物
hexachlorobenzene（HCB）
humic acid（HA）
anaerobic degradation
degradation product
