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Acta Geologica Sinica(English Edition) 2008年第4期82卷 911-916页

作者： LI Ye LIU Fei CHEN Honghan SHI Jinhua WANG Yufan School of Geoscience and Space Science Peking University Beijing 100871 China China University of Geosciences Beijing Key Laboratory of Water Resources and Environmental Engineering Beijing 100083 China

A series of batch-type experiments with acetate acid as the primary substrate were performed using enrichment cultures developed from the anaerobic sludge to investigate the effect of acetate acid on tetrachloroethylene （PCE） biodegradation. Experimental results indicated that acetate acid was an efficient electron donor in affecting the biotransformability of PCE. Trichloroethylene （TCE） was the primary dehalogenation product, and small amounts of dichloroethylenes （DCEs） were also detected. No significant further DCEs degradation was detected. PCE degradation rate in the experiment was 36.6 times faster than background rate in natural groundwater.

关键词： biodegradation co-metabolism substrate tetrachloroethylene

A reactor system combining reductive dechlorination with co-metabolic oxidation for complete degradation of tetrachloro-entylene

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Journal of Environmental Sciences 2002年第4期14卷 445-450页

作者： TAE HO LEE MICHIHIKO IKE MASANORI FUJITA Department of Environmental Engineering Osaka University 2-1 YamadaokaDepartment of Environmental Engineering Osaka University 2-1 YamadaokaDepartment of Environmental Engineering Osaka University 2-1 Yamadaoka Suita Osaka 565-0871 Japan.Suit

A laboratory sequential anaerobic aerobic bioreactor system, which consisted of an anaerobic fixed film reactor and two aerobic chemostats, was set up to degrade tetrachloroethylene (PCE) without accumulating highly toxic degradation intermediates. A soil enrichment culture, which could reductively dechlorinate 900 μM (ca. 150 mg/L) of PCE stoichiometrically into cis 1,2 dichloroethylene ( cis DCE), was attached to ceramic media in the anaerobic fixed film reactor. A phenol degrading strain, Alcaligenes sp. R5, which can efficiently degrade cis DCE by co metabolic oxidation, was used as inoculum for the aerobic chemostats consisted of a transformation reactor and a growth reactor. The anaerobic fixed film bioreactor showed more than 99 % of PCE transformation into cis DCE in the range of influent PCE concentration from 5 μM to 35 μM at hydraulic retention time of 48h. On the other hand, efficient degradation of the resultant cis DCE by strain R5 in the following aerobic system could not be achieved due to oxygen limitation. However, 54% of the maximum cis DCE degradation was obtained when 10 μmol of hydrogen peroxide (H 2O 2) was supplemented to the transformation reactor as an additional oxygen source. Further studies are needed to achieve more efficient co metabolic degradation of cis DCE in the aerobic reactor.

关键词： anaerobic aerobic bioreactor co oxidation reductive dechlorination tetrachloroethylene

Hexachlorobutadiene emissions from typical chemical plants

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Frontiers of Environmental Science & Engineering 2021年第4期15卷 77-83页

作者： Minxiang Wang Lili Yang Xiaoyun Liu Zheng Wang Guorui Liu Minghui Zheng College of Geology and Environment Xi’an University of Science and TechnologyXi’an710054China State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing100085China School of Environment Hangzhou Institute for Advanced StudyUCASHangzhou310000China

Hexachlorobutadiene(HCBD)was classed as a persistent organic pollutant under the Stockholm Convention in *** is mainly an unintentionally produced by-product of chlorinated hydrocarbon(e.g.,trichloroethylene and tetrachloroethylene)*** studies of HCBD formation during chemical production processes have been performed,so HCBD emissions from these potentially important sources are not *** this study,HCBD concentrations in raw materials,intermediate products,products,and bottom residues from chemical plants producing chlorobenzene,trichloroethylene,and tetrachloroethylene were *** results indicated that HCBD is unintentionally produced at much higher concentrations in trichloroethylene and tetrachloroethylene plants than chlorobenzene *** sum of the HCBD concentrations in the samples from all of the trichloroethylene and tetrachloroethylene production stages in plant PC was 247000µg/mL,about three orders of magnitude higher than the concentrations in the tetrachloroethylene production samples(plant PB)and about six orders of magnitude higher than the concentrations in the chlorobenzene production samples(plant PA).The HCBD concentrations were highest in bottom residues from all of the *** concentrations in the bottom residue samples contributed 24%–99%of the total HCBD formed in the chemical production *** bottom residue,being hazardous waste,could be disposed of by *** HCBD concentrations were much higher in intermediate products than raw materials,indicating that HCBD formed during production of the intended *** results indicate the concentrations of HCBD unintentionally produced in typical chemical plants and will be useful in developing protocols for controlling HCBD emissions to meet the Stockholm Convention requirements.

关键词： Hexachlorobutadiene Chemical plant Chlorobenzene Trichloroethylene tetrachloroethylene

Biodegradation of Tetrachlorothylene Using Methanol as Co-metabolic Substrate

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Biomedical and Environmental Sciences 2008年第2期21卷 98-102页

作者： QI YANG HAI-TAO SHANG Hui-DI LI HONG-BO XI JIAN-LONG WANG School of Water Resources and Environment China University of Geoscience Beijing 100083 China Laboratory of Geomicrobiology China University of Geoscience Beijing 100083 China Laboratory of Environmental Technology INET Tsinghua University Beijing 100084 China

Objective To investigate the biodegradation of tetrachloroethylene （PCE） using methanol as electron donor by acclimated anaerobic sludge. Methods HP-6890 gas chromatograph （GC）, together with HP-7694 autosarnpler, was used to analyze the concentration of PCE and intermediates. Results PCE could be decholrinated reductively to DCE via TCE, and probably further to VC and ethylene. The degradation of PCE and TCE conformed to first-order reaction kinetics. The reaction rate constants were 0.8991 d^-1 and 0.068 d^-1, respectively, and the corresponding half-life were 0.77 d and 10.19 d, respectively. TCE production rate constant was 0.1333 d^-1, showing that PCE was degraded more rapidly than TCE. Conclusion Methanol is an electron donor suitable for PCE degradation and the cometabolic electron donors are not limiting factors for PCE degradation.

关键词： tetrachloroethylene Anaerobic cometabolism Biodegradation

ENGINEERING MICROBES CAPABLE OF EFFICIENT DEGRADATION OF CHLORINATED ORGANIC POLLUTANTS

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ENGINEERING MICROBES CAPABLE OF EFFICIENT DEGRADATION OF CHL...