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Updated: Jul 4, 2025
08:46
Preparation and Reactivity of a Triphosphenium Bromide Salt: A Convenient and Stable Source of PhosphorusI
Published on: November 22, 2016
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Bromide triggers efficient peroxymonosulfate activation for phosphonate degradation
Meng Zhu1, Jinglin Zhu2, Juanjuan Peng1
1School of Earth and Environment, Anhui University of Science and Technology, Huainan, 232001, China.
Environmental Science and Pollution Research International
|February 9, 2024
Summary
Bromide significantly enhances phosphonate degradation in peroxymonosulfate (PMS) activation, unlike iodide or chloride. Bromine radicals are key to this improved removal of 1-hydroxyethane 1,1-diphosphonic acid (HEDP) in wastewater treatment.
Area of Science:
- Environmental Chemistry
- Water Treatment Technologies
- Advanced Oxidation Processes
Background:
- Phosphonates pose environmental risks, necessitating effective wastewater treatment methods.
- Advanced oxidation processes (AOPs) are viable for phosphonate degradation, but coexisting substances often hinder efficiency.
- The specific impact of bromide ions on phosphonate degradation via peroxymonosulfate (PMS) activation remains largely uninvestigated.
Purpose of the Study:
- To investigate the effect of bromide ions on the degradation of 1-hydroxyethane 1,1-diphosphonic acid (HEDP) using PMS activation.
- To elucidate the primary reactive species responsible for HEDP oxidation in the PMS/bromide system.
- To compare the efficacy of the PMS/bromide process with other AOPs for HEDP removal in real water matrices.
Main Methods:
- Utilized peroxymonosulfate (PMS) activation with bromide ions to degrade 1-hydroxyethane 1,1-diphosphonic acid (HEDP).
- Employed electron paramagnetic resonance (EPR), radical quenching experiments, and chemical probes to identify reactive species.
- Assessed the influence of various inorganic anions and humic acid on HEDP degradation and compared performance in real river and sewage water.
Main Results:
- Bromide ions significantly enhanced HEDP degradation by PMS, achieving 84.8% removal under optimal conditions (pH 7.0, 30 min).
- Bromine radical species were identified as the dominant oxidants, with free bromine, sulfate, and hydroxyl radicals playing minor roles.
- The PMS/bromide process demonstrated superior HEDP degradation efficiency in real water samples compared to UV/persulfate and UV/hydrogen peroxide methods.
Conclusions:
- Bromide ions act as a crucial enhancer for phosphonate degradation in PMS-based AOPs.
- Bromine radical species are the primary drivers of HEDP oxidation in the PMS/bromide system.
- The PMS/bromide process offers a promising and effective strategy for removing phosphonates from wastewater.
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