Enhanced dechlorination of 2,2′,4,4′,5,5′-hexachlorobiphenyl in water-sediment mixture by adding anthraquinone-2,6-disulfonic acid
Enhanced dechlorination of 2,2′,4,4′,5,5′-hexachlorobiphenyl in water-sediment mixture by adding anthraquinone-2,6-disulfonic acid
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DOI：
10.1007/s11368-015-1216-1
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发表时间：
2015
影响因子：
3.6
通讯作者：
Lei Chen;Z. Gao;Z. Wang
中科院分区：
文献类型：
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作者：
Lei Chen;Z. Gao;Z. Wang
目的多氯联苯（PCBs）在水生沉积物和厌氧生物反应器中的脱氯作用已被广泛观察到，并对其脱氯机理进行了研究。然而，腐植酸在多氯联苯生物脱氯中的作用尚未得到研究。研究了腐植酸作为氧化还原介质在水体和沉积物中多氯联苯厌氧生物转化中的作用。材料与方法通过添加不同浓度的蒽醌-2,6-二磺酸（AQDS），研究了腐殖酸中醌类成分的模式物质，对水体和沉积物中2,2′，4,4′，5,5′-六氯联苯（PCB 153）的降解作用。用无菌AH2QDS对PCB 153进行化学还原，探讨其作用机制。结果与讨论添加AQDS可显著促进pcpc153的降低。添加1 mM AQDS可使pb153培养15 d后的损失率由9.03±2.73%提高到38.3±3.27% (P= 95%)，添加5 mM乙酸钠和1 mM AQDS可使其损失率提高到46.8±4.41% （P= 95%）。氯化程度较低的同系物pc101和pc52主要是通过对pc153的脱氯而确定的产物。结论腐植酸中的醌类成分可能在自然界中多氯联苯的脱氯中起重要作用。这一发现将有助于我们更好地了解多氯联苯的自然衰减，并为在废物处理过程中加强对高氯化多氯联苯的去除提供一种方法。
PurposeDechlorination of polychlorinated biphenyls (PCBs) in aquatic sediments and anaerobic bioreactors has been widely observed, and mechanisms have also been studied. However, the role of humic acid in the biotic dechlorination of PCBs has not been studied. The present study investigated the role of humic acid as the redox mediator in the anaerobic biotransformation of PCBs in water and sediment mixture.Materials and methodsDegradation of 2,2′,4,4′,5,5′-hexachlorobiphenyl (PCB 153) in water and sediment mixture was studied by adding different concentrations of anthraquinone-2,6-disulfonic acid (AQDS), which was a model substance for quinone moieties in humic acid. Chemical reduction of PCB 153 by sterile AH2QDS was performed to investigate the mechanisms involved.Results and discussionDecrease of PCB 153 was enhanced significantly by adding AQDS. The loss percentage of PCB 153 after 15 days of incubation was increased from 9.03 ± 2.73 % to 38.3 ± 3.27 % (P= 95 %) by adding 1 mM AQDS, while it was increased to 46.8 ± 4.41 % (P= 95 %) by adding 5 mM sodium acetate and 1 mM AQDS. Less chlorinated congeners PCB 101 and PCB 52 were identified as the products through the dechlorination of PCB 153 mainly inparapositions.ConclusionsThe results suggested that the quinone moieties in humic acid may play an important role in the dechlorination of PCBs in nature. This finding will help us to understand the natural attenuation of PCBs better and also provide a method to enhance the removal of higher chlorinated PCBs in waste treatment process.