Halogen Radical Oxidants in Natural and Engineered Aquatic Systems
1Department of Energy, Environmental & Chemical Engineering , Washington University in St. Louis , Brauer Hall, 1 Brookings Dr. , St Louis , Missouri 63130 , United States.
Environmental Science & Technology
|August 7, 2018
Summary
Halogen radicals significantly influence aquatic photochemistry in natural and engineered systems. Understanding their reactivity is key to assessing their impact on contaminant transformation and water treatment.
Area of Science:
- Environmental Chemistry
- Photochemistry
- Aquatic Science
Background:
- Photochemical reactions are vital for transforming contaminants and substrates in aquatic environments.
- Halogen radicals (e.g., chlorine, bromine) play a crucial role in sunlit estuarine and coastal waters.
- These radicals are also involved in engineered water treatment processes.
Purpose of the Study:
- To review the chemistry of halogen radicals in aquatic photochemistry.
- To analyze their contribution to both natural surface waters and engineered treatment systems.
- To identify knowledge gaps and uncertainties regarding their impact.
Main Methods:
- Literature review and data synthesis.
- Evaluation of experimental and computational approaches.
- Analysis of halogen radical generation, speciation, and reactivity.
Main Results:
- Halogen radicals exhibit selective reactivity with various substrates.
- Their complex reaction mechanisms pose challenges in assessing their overall impact.
- Existing data provides a foundation for understanding their role.
Conclusions:
- Halogen radicals are critical players in aquatic photochemistry.
- Further research is needed to fully elucidate their impact on contaminant degradation and water treatment.
- This review provides a basis for future assessments in saline environments and engineered systems.
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