Evaluating hexavalent chromium reduction and electricity production in microbial fuel cells with alkaline cathodes
Evaluating hexavalent chromium reduction and electricity production in microbial fuel cells with alkaline cathodes
The work investigated the efficiency of microbial fuel cells (MFCs) for the treatment of alkaline hexavalent chromium containing wastewater. When lactate was used as the metal chelator in alkaline (pH 8) abiotic cathodes, hexavalent chromium concentration dropped from 10 mg l?1 to undetectable levels within the first 45 h of operation. Power density produced in the pH 8 abiotic cathodes was up to 21.4 mW m?2, and in the pH 9 cathodes up to 2.4 mW m?2; these values were well comparable with other values found in the literature for biologically catalysed cathodes, even at lower pH values. When Shewanella oneidensis MR-1 was present in a hexavalent chromium reducing cathode at pH 8, current production contributed by 26 % to the total hexavalent chromium reduced during the 36 days of operation. On the other hand, when hexavalent chromium (10 mg l?1) was controllably added in the anode where S. oneidensis MR-1 was present, up to 73 % of current decreased immediately after every hexavalent chromium addition; this toxic effect remained even after hexavalent chromium was depleted in the anode and strongly indicates that the presence of hexavalent chromium in the anodes of MFCs must be avoided. Overall, our results indicate that alkaline hexavalent chromium wastewater can be effectively remediated in the cathodes of MFCs, provided that a metal chelator is present in the cathodes and that hexavalent chromium is not present in the anodes.
bioelectrochemical systems, hexavalent chromium remediation, shewanella oneidensis MR-1, lactate, high pH, hexavalent chromium toxicity
2435-2446
Xafenias, Nikolaos
45fb5b87-a363-4080-96e4-af6fdf578956
Zhang, Yue
69b11d32-d555-46e4-a333-88eee4628ae7
Banks, Charles J.
5c6c8c4b-5b25-4e37-9058-50fa8d2e926f
August 2015
Xafenias, Nikolaos
45fb5b87-a363-4080-96e4-af6fdf578956
Zhang, Yue
69b11d32-d555-46e4-a333-88eee4628ae7
Banks, Charles J.
5c6c8c4b-5b25-4e37-9058-50fa8d2e926f
Xafenias, Nikolaos, Zhang, Yue and Banks, Charles J.
(2015)
Evaluating hexavalent chromium reduction and electricity production in microbial fuel cells with alkaline cathodes.
International Journal of Environmental Science and Technology, 12 (8), .
(doi:10.1007/s13762-014-0651-7).
Abstract
The work investigated the efficiency of microbial fuel cells (MFCs) for the treatment of alkaline hexavalent chromium containing wastewater. When lactate was used as the metal chelator in alkaline (pH 8) abiotic cathodes, hexavalent chromium concentration dropped from 10 mg l?1 to undetectable levels within the first 45 h of operation. Power density produced in the pH 8 abiotic cathodes was up to 21.4 mW m?2, and in the pH 9 cathodes up to 2.4 mW m?2; these values were well comparable with other values found in the literature for biologically catalysed cathodes, even at lower pH values. When Shewanella oneidensis MR-1 was present in a hexavalent chromium reducing cathode at pH 8, current production contributed by 26 % to the total hexavalent chromium reduced during the 36 days of operation. On the other hand, when hexavalent chromium (10 mg l?1) was controllably added in the anode where S. oneidensis MR-1 was present, up to 73 % of current decreased immediately after every hexavalent chromium addition; this toxic effect remained even after hexavalent chromium was depleted in the anode and strongly indicates that the presence of hexavalent chromium in the anodes of MFCs must be avoided. Overall, our results indicate that alkaline hexavalent chromium wastewater can be effectively remediated in the cathodes of MFCs, provided that a metal chelator is present in the cathodes and that hexavalent chromium is not present in the anodes.
Text
Xafenias Zhang Banks- Alkaline Cr(VI) _ authors copy
- Accepted Manuscript
More information
e-pub ahead of print date: 23 July 2014
Published date: August 2015
Keywords:
bioelectrochemical systems, hexavalent chromium remediation, shewanella oneidensis MR-1, lactate, high pH, hexavalent chromium toxicity
Organisations:
Faculty of Engineering and the Environment
Identifiers
Local EPrints ID: 366789
URI: http://eprints.soton.ac.uk/id/eprint/366789
ISSN: 1735-1472
PURE UUID: 93088c8b-76ce-4b71-ae92-6f0df5e18b05
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Date deposited: 17 Jul 2014 08:21
Last modified: 15 Mar 2024 03:15
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Author:
Nikolaos Xafenias
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