Reductive Dechlorination Of Tetrachloroethylene by a Chlorobenzoate-Enriched Biofilm Reactor

1994 ◽  
Vol 28 (4) ◽  
pp. 746-752 ◽  
Author(s):  
Babu Z. Fathepure ◽  
James M. Tiedje
Keyword(s):  
Reductive Dechlorination ◽  
Biofilm Reactor

scholarly journals Coupled Adsorption and Biodegradation of Trichloroethylene on Biochar from Pine Wood Wastes: A Combined Approach for a Sustainable Bioremediation Strategy

2022 ◽  
Vol 10 (1) ◽  
pp. 101
Author(s):  
Marta M. Rossi ◽  
Bruna Matturro ◽  
Neda Amanat ◽  
Simona Rossetti ◽  
Marco Petrangeli Papini
Keyword(s):  
Reductive Dechlorination ◽  
Adsorption Mechanism ◽  
Biological Process ◽  
Chlorinated Solvents ◽  
Biofilm Reactor ◽  
Rrna Gene ◽  
Pine Wood ◽  
Dehalococcoides Mccartyi ◽  
Gene Copies ◽  
Physical Treatments

Towards chlorinated solvents, the effectiveness of the remediation strategy can be improved by combining a biological approach (e.g., anaerobic reductive dechlorination) with chemical/physical treatments (e.g., adsorption). A coupled adsorption and biodegradation (CAB) process for trichloroethylene (TCE) removal is proposed in a biofilm–biochar reactor (BBR) to assess whether biochar from pine wood (PWB) can support a dechlorinating biofilm by combining the TCE (100 µM) adsorption. The BBR operated for eight months in parallel with a biofilm reactor (BR)—no PWB (biological process alone), and with an abiotic biochar reactor (ABR)—no dechlorinating biofilm (only an adsorption mechanism). Two flow rates were investigated. Compared to the BR, which resulted in a TCE removal of 86.9 ± 11.9% and 78.73 ± 19.79%, the BBR demonstrated that PWB effectively adsorbs TCE and slows down the release of its intermediates. The elimination of TCE was quantitative, with 99.61 ± 0.79% and 99.87 ± 0.51% TCE removal. Interestingly, the biomarker of the reductive dechlorination process, Dehalococcoides mccartyi, was found in the BRR (9.2 × 105 16S rRNA gene copies/g), together with the specific genes tceA, bvcA, and vcrA (8.16 × 106, 1.28 × 105, and 8.01 × 103 gene copies/g, respectively). This study suggests the feasibility of biochar to support the reductive dechlorination of D. mccartyi, opening new frontiers for field-scale applications.

Managing methanogens and homoacetogens to promote reductive dechlorination of trichloroethene with direct delivery of H2 in a membrane biofilm reactor

2012 ◽  
Vol 109 (9) ◽  
pp. 2200-2210 ◽  
Author(s):  
Michal Ziv-El ◽  
Sudeep C. Popat ◽  
Katherine Cai ◽  
Rolf U. Halden ◽  
Rosa Krajmalnik-Brown ◽  
...  
Keyword(s):  
Reductive Dechlorination ◽  
Biofilm Reactor ◽  
Membrane Biofilm Reactor ◽  
Direct Delivery

Reductive dechlorination of perchloroethylene using anaerobic sequencing batch biofilm reactors (AnSBBR)

1997 ◽  
Vol 35 (1) ◽  
pp. 49-56 ◽  
Author(s):  
P. J. Hirl ◽  
R. L. Irvine
Keyword(s):  
Reductive Dechlorination ◽  
Physiological State ◽  
Accurate Method ◽  
The United States ◽  
Daily Basis ◽  
Biofilm Reactor ◽  
Microbial Consortia ◽  
Biofilm Reactors ◽  
Chlorinated Organic ◽  
The Many

Chlorinated organic solvents, such as perchloroethylene (PCE) and trichloroethylene (TCE), rank in the top five of the groundwater pollutants found in the United States. During the past year, the Anaerobic Sequencing Batch Biofilm Reactor (AnSBBR) was used to select for, enrich, and modify the physiological state of one or more of the many possible microbial consortia that can participate in the reductive dechlorination of PCE. Reactors enriched on lactate or acetate were able to dechlorinate 10.5 mg (63.3 μmoles) of PCE to cis-1,2-dichloroethylene (cDCE) on a daily basis. When methanol was used as the electron donor PCE, TCE, and cDCE were detectable in the reactor at the end of a 24 hour cycle. An AnSBBR fed only H2/CO2 was able to mediate the dechlorination of PCE to TCE, cDCE, and vinyl chloride (VC). Chloride measurements provided for a reliable and accurate method for the quantification of reductive dechlorination when the sorption of the chlorinated ethylenes affected the direct measurement of these compounds.

Reductive Dehalogenation of Environmental Contaminants: A Critical Review

1989 ◽  
Vol 24 (2) ◽  
pp. 299-322 ◽  
Author(s):  
R. M. Baxter
Keyword(s):  
Hydrogen Atom ◽  
Aromatic Compounds ◽  
Reductive Dechlorination ◽  
Halogen Atom ◽  
Environmental Contaminants ◽  
Methanogenic Bacteria ◽  
Photochemical Reactions ◽  
Reductive Dehalogenation ◽  
Iron Porphyrins ◽  
Aliphatic Compounds

Abstract It is generally recognized that reductive processes are more important than oxidative ones in transforming, degrading and mineralizing many environmental contaminants. One process of particular importance is reductive dehalogenation, i.e., the replacement of a halogen atom (most commonly a chlorine atom) by a hydrogen atom. A number of different mechanisms are involved in these reactions. Photochemical reactions probably play a role in some instances. Aliphatic compounds such as chloroethanes, partly aliphatic compounds such as DDT, and alicyclic compounds such as hexachlorocyclohexane are readily dechlorinated in the laboratory by reaction with reduced iron porphyrins such as hematin. Many of these are also dechlorinated by cultures of certain microorganisms, probably by the same mechanism. Such compounds, with a few exceptions, have been found to undergo reductive dechlorination in the environment. Aromatic compounds such as halobenzenes, halophenols and halobenzoic acids appear not to react with reduced iron porphyrins. Some of these however undergo reductive dechlorination both in the environment and in the laboratory. The reaction is generally associated with methanogenic bacteria. There is evidence for the existence of a number of different dechlorinating enzymes specific for different isomers. Recently it has been found that many components of polychlorinated biphenyls (PCBs), long considered to be virtually totally resistant to environmental degradation, may be reductively dechlorinated both in the laboratory and in nature. These findings suggest that many environmental contaminants may prove to be less persistent than was previously feared.

Phosphorus Release Kinetics in Biofilm Reactors

1992 ◽  
Vol 26 (3-4) ◽  
pp. 567-576 ◽  
Author(s):  
F. A. Ruiz-Treviño ◽  
S. González-Martínez ◽  
C. Doria-Serrano ◽  
M. Hernández-Esparza
Keyword(s):  
Phosphorus Removal ◽  
Release Kinetics ◽  
Phosphorus Release ◽  
Organic Substrate ◽  
Biofilm Reactor ◽  
Substrate Uptake ◽  
Biofilm Reactors ◽  
Initial Substrate ◽  
Linear Behaviour ◽  
Substrate Concentrations

This paper presents the kinetic analysis, using Generalized Power-Law equations to describe the results of an experimental investigation conducted on a batch submerged biofilm reactor for phosphorus removal under an anaerobic/aerobic cycle. The observed rates and amounts of phosphorus release and organic substrate uptake in the anaerobic phase leads to a kinetic model in which these two variables are dependent on each other with a non-linear behaviour and reach equilibrium values in both cases, at different times and are function of rate constants ratio. The model has a good fit with experimental data except for C uptake at anaerobic contact times longer than four hours, where other kinetics are implied. Kinetic parameters were obtained with different initial substrate concentrations, anaerobic contact cycles, and type of substrates.

Anaerobic Thermophilic (55°C) Treatment of TMP Whitewater in Reactors Based on Biomass Attachment and Entrapment

1999 ◽  
Vol 40 (11-12) ◽  
pp. 67-75 ◽  
Author(s):  
Sigrun J. Jahren ◽  
Jukka A. Rintala ◽  
Hallvard Ødegaard
Keyword(s):  
Granular Sludge ◽  
Biofilm Reactor ◽  
Upflow Anaerobic Sludge Blanket ◽  
Hybrid Reactor ◽  
Anaerobic Sludge ◽  
Loading Rates ◽  
Anaerobic Reactors ◽  
Multi Stage ◽  
Degradation Rates ◽  
Thermomechanical Pulping

Thermomechanical pulping (TMP) whitewater was treated in thermophilic (55°C) anaerobic laboratory-scale reactors using three different reactor configurations. In all reactors up to 70% COD removals were achieved. The anaerobic hybrid reactor, composed of an upflow anaerobic sludge blanket (UASB) and a filter, gave degradation rates up to 10 kg COD/m3d at loading rates of 15 kg COD/m3d and hydraulic retention time (HRT) of 3.1 hours. The anaerobic multi-stage reactor, consisting of three compartments, each packed with granular sludge and carrier elements, gave degradation rates up to 9 kg COD/m3d at loading rates of 15-16 kg COD/m3d, and HRT down to 2.6 hours. Clogging and short circuiting eventually became a problem in the multi-stage reactor, probably caused by too high packing of the carriers. The anaerobic moving bed biofilm reactor performed similar to the other reactors at loading rates below 1.4 kg COD/m3d, which was the highest loading rate applied. The use of carriers in the anaerobic reactors allowed short HRT with good treatment efficiencies for TMP whitewater.

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