Auxiliary Substrates for Elimination of Trichloroethene, Monochlorobenzene, and Benzene in a Sequential Anaerobic–Aerobic GAC Biobarrier

Sequential anaerobic-aerobic barrier is a novel concept for groundwater bioremediation. Trichloroethene (TCE), monochlorobenzene (MCB), and benzene (BZ) were used as model contaminants representing contaminant cocktails frequently found in the contaminated subsurface. The autochthonous microflora from a contaminated field was inoculated to eliminate model contaminants in a set of sequential anaerobic–aerobic granulated activated carbon (GAC) columns and batch studies. In the anaerobic column, the TCE was reductively dechlorinated through cis-dichloroethene (cis-DCE), vinyl chloride (VC), and ethene (ETH). Ethanol and sucrose as auxiliary substrates were added to donate electrons. In the second stage, MCB, BZ, and the lower chlorinated metabolites of TCE degradation, i.e. cis-Dichloroethene (cisDCE) and vinyl chloride (VC), were oxidatively degraded with addition of hydrogen peroxide and nitrate. This paper examines the influence of auxiliary substrates on the biological degradation of model pollutants. In the anaerobic barrier, the auxiliary substrates supply should be maintained low but stoichiometrically adequate for supporting reductive dechlorination. Supplying higher amount of auxiliary substrates provoked competitive reactions in anaerobic conditions, such as sulfate reduction and methanogenesis. If the auxiliary substrates are not utilized completely in the anaerobic phase, the remaining compounds flow into the aerobic phase. This led to unwanted conditions, i.e. oxidation of auxiliary substrates instead of pollutant elimination, and a higher consumption of electron acceptors. In the aerobic barrier, in particular, ethene proved to be a suitable auxiliary substrate for cometabolic degradation of cisDCE.

Download Full-text

Sequential anaerobic/aerobic biodegradation of chlorinated hydrocarbons in activated carbon barriers

Water Science & Technology Water Supply ◽

10.2166/ws.2002.0045 ◽

2002 ◽

Vol 2 (2) ◽

pp. 51-58 ◽

Cited By ~ 3

Author(s):

A. Tiehm ◽

M. Gozan ◽

A. Müller ◽

H. Schell ◽

H. Lorbeer ◽

...

Keyword(s):

Hydrogen Peroxide ◽

Biological Activity ◽

Activated Carbon ◽

Vinyl Chloride ◽

Reductive Dechlorination ◽

Chlorinated Hydrocarbons ◽

Aerobic Biodegradation ◽

Anaerobic Conditions ◽

Biological Activated Carbon ◽

Batch Tests

The aim of this study is to develop a long lasting, sequential anaerobic/aerobic biological activated carbon barrier. In the biobarrier, pollutant adsorption on granular activated carbon (GAC) and biodegradation occur simultaneously. Trichloroethene (TCE), chlorobenzene (CB), and benzene were used as model pollutants. In the first barrier, that was operated under anaerobic conditions with sucrose and ethanol as auxiliary substrates, TCE was completely converted to lower chlorinated metabolites, predominantly cis-dichloroethene (cis-DCE). The reductive dechlorination process was stable for about 300 d, although the concomitant sulphate-reducing and methanogenic processes varied considerably. In the second barrier, that was operated with addition of hydrogen peroxide and nitrate, dechlorination was limited by a lack of oxygen and restricted mainly to CB biodegradation. Additional aerobic batch tests revealed that the metabolites of anaerobic TCE dechlorination, i.e. cis-DCE and vinyl chloride, were oxidatively dechlorinated in the presence of suitable auxiliary substrates such as ethene, CB, benzene, or sucrose and ethanol. During periods of low biological activity, elimination of TCE and CB occurred by adsorption in the GAC barriers. The pre-sorbed pollutants were available for subsequent biodegradation resulting in a bioregeneration of the activated carbon barriers.

Download Full-text

Biological effects of tourmaline treatment on Dehalococcoides spp. during the reductive dechlorination of trichloroethylene

RSC Advances ◽

10.1039/d0ra10830h ◽

2021 ◽

Vol 11 (20) ◽

pp. 12086-12094

Author(s):

Tielong Li ◽

Jiaxin Wen ◽

Bingjie Li ◽

Shihu Ding ◽

Wei Wang

Keyword(s):

Gene Expression ◽

Cell Proliferation ◽

Community Structure ◽

Reductive Dechlorination ◽

Biological Effects ◽

Dechlorinating Bacteria ◽

Contaminated Aquifers ◽

Tce Degradation ◽

Induced Changes

To explore the application of mineral in bioremediation of contaminated aquifers, this study investigated tourmaline-induced changes in TCE degradation, community structure, cell proliferation and gene expression of dechlorinating bacteria.

Download Full-text

Geochemical Parameters and Reductive Dechlorination Determine Aerobic Cometabolic vs Aerobic Metabolic Vinyl Chloride Biodegradation at Oxic/Anoxic Interface of Hyporheic Zones

Environmental Science & Technology ◽

10.1021/acs.est.6b05041 ◽

2017 ◽

Vol 51 (3) ◽

pp. 1626-1634 ◽

Cited By ~ 13

Author(s):

Siavash Atashgahi ◽

Yue Lu ◽

Javier Ramiro-Garcia ◽

Peng Peng ◽

Farai Maphosa ◽

...

Keyword(s):

Vinyl Chloride ◽

Reductive Dechlorination ◽

Geochemical Parameters ◽

Hyporheic Zones

Download Full-text

Reductive Dechlorination of Methoxychlor and DDT by Human Intestinal Bacterium Eubacterium limosum Under Anaerobic Conditions

Archives of Environmental Contamination and Toxicology ◽

10.1007/s00244-007-9044-y ◽

2007 ◽

Vol 54 (3) ◽

pp. 406-411 ◽

Cited By ~ 25

Author(s):

You-Jin Yim ◽

Jiyoung Seo ◽

Su-Il Kang ◽

Joong-Hoon Ahn ◽

Hor-Gil Hur

Keyword(s):

Reductive Dechlorination ◽

Intestinal Bacterium ◽

Anaerobic Conditions ◽

Eubacterium Limosum

Download Full-text

Reductive dechlorination pathways of chloro organics under anaerobic conditions

Water Science & Technology ◽

10.2166/wst.1996.0587 ◽

1996 ◽

Vol 34 (5-6) ◽

pp. 489-494 ◽

Cited By ~ 4

Author(s):

Sridhar Susarla ◽

Shigeki Masunaga ◽

Yoshitaka Yonezawa

Keyword(s):

Reductive Dechlorination ◽

Organic Chemicals ◽

Anaerobic Conditions ◽

Sediment Slurry ◽

Transformation Pathways ◽

Lag Period ◽

Cl Atoms ◽

Cl Atom

The transformation pathways of chloroanilines (CAs), chlorobenzenes (CBs) and chlorophenols (CPs) were examined in anaerobic sediment collected from the Tsurumi river, Japan. The sediment was pre-exposed to various organic chemicals from the surrounding industries and appears to be sulfidogenic. Experiments were carried out for each compound in the sediment slurry, which was spiked at a desired concentration. The transformation of the parent substrate and the appearance of its metabolites were monitored for a year. All the compounds transformed without any lag period. For CBs, the preferential Cl removal was in the order: two Cl atoms on adjacent carbon atoms > one Cl atom on adjacent carbon > no adjacent Cl atom on the carbon. In case of CPs, ortho dechlorination was the preferred pathway, while for CAs, sequential removal of ortho and para positions was observed.

Download Full-text

Carbon and Chlorine Isotope Fractionation during Aerobic Oxidation and Reductive Dechlorination of Vinyl Chloride andcis-1,2-Dichloroethene

Environmental Science & Technology ◽

10.1021/es801759k ◽

2009 ◽

Vol 43 (1) ◽

pp. 101-107 ◽

Cited By ~ 104

Author(s):

Y. Abe ◽

R. Aravena ◽

J. Zopfi ◽

O. Shouakar-Stash ◽

E. Cox ◽

...

Keyword(s):

Vinyl Chloride ◽

Reductive Dechlorination ◽

Isotope Fractionation ◽

Aerobic Oxidation ◽

Chlorine Isotope

Download Full-text

Influence of Different Salts on the Degradation of Trichloroethylene under Reductive Condition

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.356-360.1689 ◽

2011 ◽

Vol 356-360 ◽

pp. 1689-1692

Author(s):

Feng Na Ma ◽

Qing Jun Meng ◽

Guo Jun Wu ◽

Ai Qin Shan

Keyword(s):

Electron Donor ◽

Anaerobic Condition ◽

Anoxic Condition ◽

Trivalent Iron ◽

Anaerobic Conditions ◽

Iron Salts ◽

Anoxic Environment ◽

Mixed Salts ◽

Tce Degradation

The effect of TCE cometabolism degradation with glucose as electron donor on reduction progress was investigated with enriched nitrate, sulfate, trivalent iron and their mixtures under anoxic or anaerobic conditions. The removal effect of TCE was found to be better in anoxic environment; TCE degradation was inhibited by the addition of trivalent iron salts and the mixed salts under anoxic condition or strongly inhibited by nitrate under anaerobic condition; promoted by the addition of trivalent iron salts under anaerobic condition; little inhibited by the addition of nitrate and sulfate under anoxic condition or sulfate and the mixed salts under anaerobic condition.

Download Full-text

Anaerobic treatment of sludge: focusing on reduction of las concentration in sludge

Water Science & Technology ◽

10.2166/wst.2002.0318 ◽

2002 ◽

Vol 46 (10) ◽

pp. 159-165 ◽

Cited By ~ 20

Author(s):

F. Haggensen ◽

A.S. Mogensen ◽

I. Angelidaki ◽

B.K. Ahring

Keyword(s):

Organic Matter ◽

Anaerobic Treatment ◽

Clear Correlation ◽

Biological Degradation ◽

Anaerobic Conditions ◽

Linear Alkylbenzene ◽

Stirred Tank Reactors ◽

Bioavailable Fraction ◽

Solids Concentration ◽

Linear Alkylbenzene Sulfonates

Anaerobic degradation of linear alkylbenzene sulfonates (LAS) was tested in continuous stirred tank reactors (CSTR). LAS12 was used as a model compound and was spiked on sewage sludge. The experiments clearly showed that transformation of LAS12 occurred under anaerobic conditions. The degree of transformation varied between 14% and 25%. HPLC analysis showed that disappearance of LAS12 was followed by the formation of a metabolite. The experiments indicated that there is a clear correlation between degradation of organic matter contained in sludge and transformation of LAS12. When the reduction degree of the organic matter increased from 22% to 28%, the transformation degree of LAS12 also increased, from 14% to 20%. Decreasing the total solids concentration of the influent sludge or increasing the spiked concentration of LAS12 did not alter the degree of LAS12 transformation significantly. A clear correlation between transformed and bioavailable LAS12 was found, indicating that it is merely the bioavailable fraction of LAS12 that is transformed by anaerobic digestion. The results from the present study are promising and indicate that a great potential for biological degradation of LAS is possible even at anaerobic conditions.

Download Full-text

A Batch Study of the Aerobic and Anaerobic Removal of Chlorinated Organic Compounds in an Aerated Lagoon

Water Quality Research Journal ◽

10.2166/wqrj.1992.039 ◽

1992 ◽

Vol 27 (3) ◽

pp. 621-638 ◽

Cited By ~ 4

Author(s):

Alexandra Chernysh ◽

Steven N. Liss ◽

D. Grant Allen

Keyword(s):

Kraft Pulp ◽

Pulp Mill ◽

Anaerobic Conditions ◽

Chlorinated Organic Compounds ◽

Batch Studies ◽

Bleached Kraft Pulp ◽

Organic Halogen ◽

Significant Difference ◽

Chlorinated Organic ◽

Aerobic And Anaerobic

Abstract In order to further our understanding of the removal of adsorbable organic halogen (AOX) from bleached kraft pulp mill effluent in an operating lagoon, controlled batch studies (at 22°C and 30°C) were conducted under aerobic and anaerobic conditions. The removal of AOX ranged from 17 to 70% and the presence of sludge significantly increased the removal of both AOX and total organic carbon (TOC). There was no further significant removal of AOX beyond two days for the aerobic experiments and beyond 10 days for the anaerobic experiments. The removal of AOX under anaerobic conditions was not significantly different from those under aerobic conditions and increasing the temperature caused a significant increase in the removal of AOX. There was no significant difference in the overall removal or patterns of removal between AOX and TOC. A mass balance showed that the sludge represented the major fraction of organically bound chlorine in the mixed liquor.

Download Full-text