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Updated: Jul 21, 2025
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Electrochemically and Bioelectrochemically Induced Ammonium Recovery
Published on: January 22, 2015
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Enhancement of Ammonium Oxidation at Microoxic Bioanodes
Xiaofang Yan1, Dandan Liu2, Johannes B M Klok3
1Environmental Technology, Wageningen University & Research, P.O. Box 17, 6700 AA Wageningen, The Netherlands.
Environmental Science & Technology
|July 27, 2023
Summary
Bioelectrochemical systems (BESs) efficiently convert ammonium in wastewater. Microoxic conditions significantly enhance ammonium oxidation rates by forming hydroxylamine, improving wastewater treatment.
Area of Science:
- Environmental Science
- Electrochemistry
- Microbiology
Background:
- Bioelectrochemical systems (BESs) offer energy-efficient wastewater treatment.
- Industrial application of BESs for ammonium removal is limited by slow rates and pathway ambiguity.
Purpose of the Study:
- To investigate ammonium oxidation rates and pathways in BESs under varying oxygen conditions.
- To elucidate the role of hydroxylamine in microoxic and anoxic ammonium conversion.
Main Methods:
- Utilized bioelectrochemical systems for ammonium conversion experiments.
- Operated systems under controlled microoxic (0.02-0.2 mg-O2/L) and anoxic conditions.
- Analyzed ammonium oxidation rates and end-product formation.
Main Results:
- Achieved ammonium oxidation rates of 228 ± 0.4 g-N m-3 d-1 under microoxic conditions, significantly higher than anoxic rates (120 ± 21 g-N m-3 d-1).
- Identified hydroxylamine (NH2OH) as a key intermediate, influencing the rate-limiting step of ammonium oxidation.
- Observed dinitrogen gas as the dominant end-product, with 75% efficiency in microoxic and 100% in anoxic conditions.
Conclusions:
- Microoxic conditions enhance ammonium oxidation in BESs, primarily through hydroxylamine formation.
- Understanding these pathways is crucial for advancing BES technology for industrial wastewater treatment.
- This study provides insights into optimizing BES performance for efficient ammonium removal.
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