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Updated: Jun 27, 2025
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Electrochemically and Bioelectrochemically Induced Ammonium Recovery
Published on: January 22, 2015
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A sequencing electroreduction-electrooxidation system driven by atomic hydrogen for enhancing
Jia Yuan1, Xi Chen1, Xueye Wang1
1State Key Laboratory of Pollution Control and Resource Reuse, Shanghai Institute of Pollution Control and Ecological Security, School of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai, 200092, China; Tongji Advanced Membrane Technology Center, Shanghai, 200092, China.
Environmental Research
|April 25, 2024
Summary
This study introduces a novel electroreduction-electrooxidation process for degrading chloronitrobenzenes (CNBs) in wastewater. The method effectively removes contaminants and reduces toxicity using atomic hydrogen and hydroxyl radicals.
Area of Science:
- Environmental Chemistry
- Electrochemistry
- Water Treatment
Background:
- Chloronitrobenzenes (CNBs) are persistent organic pollutants.
- Conventional treatment methods often struggle with complete degradation.
- Sequencing electroreduction-electrooxidation offers a promising alternative.
Purpose of the Study:
- To develop an efficient electroreduction-electrooxidation system for CNB degradation.
- To investigate the roles of atomic hydrogen (H*) and hydroxyl radicals (•OH).
- To assess the system's effectiveness in removing 2,4-DCNB and reducing effluent toxicity.
Main Methods:
- Development of a palladium (Pd) atom on titanium (Ti) plate cathode.
- Electrocatalytic generation of H* and activation of H₂O₂ to •OH.
- Verification of H* and •OH using cyclic voltammetry (CV) and electron spin resonance (ESR).
Main Results:
- Achieved 94.7% removal of 2,4-DCNB (20 mg L⁻¹) with 5 mM H₂O₂.
- Significantly reduced the inhibition rate of Photobacterium phosphoreum from 95% to 52%.
- Confirmed H* as the dominant species in electroreduction, initiating electrooxidation.
Conclusions:
- The developed Pd/Ti cathode system effectively degrades CNBs via electroreduction-electrooxidation.
- The process is efficient in removing electron-withdrawing groups from aromatic contaminants.
- This approach offers a viable solution for treating contaminated water and wastewater.
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