Abstract
The contamination of water by chlorinated solvents is recognized as a serious and widespread problem throughout the industrialized world. Here, we focus on three chlorinated solvents that are among those most commonly detected and that have distinct chemical features: trichloroethene (TCE), trichloroethane (TCA), and chloroform (CF). Because many contaminated waters contain mixtures of the chlorinated solvents, a treatment technology that detoxifies all of them simultaneously is highly desirable. The membrane biofilm reactor (MBfR) is a recent technological advance that makes it possible to deliver H2 gas to bacteria efficiently and safely, despite hydrogen's low water solubility and risk of forming a combustible atmosphere when mixed with air. The objectives of this work are to document whether or not the three chlorinated compounds can be dechlorinated simultaneously in a H2-based MBfR and to determine if competitive or inhibitory interactions affect bio-reduction of any of the solvents. The main finding is a demonstration that directly using H2 as the electron donor makes it possible to bio-reduce combinations of different chlorinated solvents. This finding supports that the H2-based MBfR can treat multiple chlorinated solvents in one step, addressing a common groundwater situation. We saw possible evidence of inhibition by CF at a concentration greater than about 1 μM, competition for H2 from sulfate and nitrate reductions, and possible inhibition of TCE reduction from the accumulation of chloroethane (CA) or chloromethane (CM).
Original language | English (US) |
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Pages (from-to) | 495-501 |
Number of pages | 7 |
Journal | Water Science and Technology |
Volume | 58 |
Issue number | 3 |
DOIs | |
State | Published - 2008 |
Keywords
- Chloroform
- Hydrogen
- Membrane biofilm reactor
- Reductive dechlorination
- Trichloroethane
- Trichloroethene
ASJC Scopus subject areas
- Environmental Engineering
- Water Science and Technology