• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Journal of Chemical Technology & Biotechnology >Enhancement of microbial reductive dechlorination of polychlorinated biphenyls (PCBs) in a marine sediment by nanoscale zerovalent iron (NZVI) particles
【24h】

Enhancement of microbial reductive dechlorination of polychlorinated biphenyls (PCBs) in a marine sediment by nanoscale zerovalent iron (NZVI) particles

机译：纳米零价铁（NZVI）颗粒增强海洋沉积物中多氯联苯（PCBs）的微生物还原脱氯

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Microbial reductive dechlorination of polychlorinated biphenyls (PCBs) in contaminated sediments is characterized by long lag periods and low rates. Zerovalent iron is a source of cathodic hydrogen that has been proposed as an easily amendable agent to stimulate PCB microbial dechlorination. The objective of this study was to evaluate the effect of nanoscale zerovalent iron (NZVI) particles on the reductive dechlorination of Aroclor 1254 PCBs and on the indigenous microbial community in a marine sediment under in situ-like biogeochemical conditions. Results: A 30-weeks lag phase followed by a modest dechlorination (5.0 ± 0.4 mol%) of hepta- through penta-chlorinated PCBs occurred in NZVI-free cultures during 36 weeks of incubation. NZVI (6.7 g kg ~(-1)) reduced the lag phase of PCB dechlorination by 10 weeks, leading to a four-fold increase of the dechlorination extent at the end of the incubation. NVZI exerted some toxic effect on sulphate reducing bacteria, which were transiently inhibited until its complete oxidation occurred, and favoured the enrichment of a phylotype closely related to the PCB dehalorespiring bacterium Dehalobium chlorocoercia DF-1, probably via the simultaneous partial inhibition of sulphate reducing bacteria and the release of molecular hydrogen. Finally, DGGE analysis showed that NZVI did not affect markedly the biodiversity of the indigenous microbial community. Conclusion: NZVI displayed a very high biostimulation effect on PCB microbial dechlorination and a very low impact on the sediment indigenous microbial community. Supplementation with NZVI particles might thus be a sustainable effective strategy to intensify PCB reductive dechlorination processes in marine sediments.
机译：污染沉积物中多氯联苯（PCBs）的微生物还原脱氯的特征在于滞后时间长且速率低。零价铁是阴极氢的一种来源，已被提议作为刺激PCB微生物脱氯的易修正剂。这项研究的目的是评估在原位生物地球化学条件下，纳米级零价铁（NZVI）颗粒对Aroclor 1254 PCBs还原脱氯以及海洋沉积物中土著微生物群落的影响。结果：在无NZVI的培养液中，经过36周的温育，出现了30周的滞后阶段，随后通过五氯化PCBs进行的七氯到七氯的适度脱氯（5.0±0.4 mol％）。 NZVI（6.7 g kg〜（-1））将PCB脱氯的滞后阶段减少了10周，导致孵育结束时脱氯程度增加了四倍。 NVZI对硫酸盐还原菌产生了一定的毒性作用，这些毒性被暂时抑制直到其完全氧化，并倾向于富集与PCB脱呼吸细菌Dehalobium chlorocoercia DF-1密切相关的系统型，可能是通过同时部分抑制硫酸盐还原菌来实现的。并释放出氢分子。最后，DGGE分析表明，NZVI并没有显着影响土著微生物群落的生物多样性。结论：NZVI对PCB微生物的脱氯表现出很高的生物刺激作用，对沉积物原生微生物群落的影响却很小。因此，补充NZVI颗粒可能是加强海洋沉积物中PCB还原性脱氯过程的可持续有效策略。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号