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[Study on bromate formation of catalytic ozonation process]
Lin Wu1, Hong-Wei Yang, Shao-Xia Yang
1School of Chemistry and Environment, South China Normal University, Guangzhou 510006, China. wulin.peiking@gmail.com
Huan Jing Ke Xue= Huanjing Kexue
|May 25, 2012
Summary
Catalytic ozonation using heterogeneous catalysts like NiO and CuO effectively minimizes bromate (BrO3-) formation in Yellow River water. This process also aids in oxidizing organic compounds, improving water quality.
Area of Science:
- Environmental Chemistry
- Water Treatment Technologies
- Catalysis
Context:
- Bromate (BrO3-) is a disinfection byproduct formed during ozonation of bromide-containing water.
- Yellow River water presents challenges due to its bromide content and organic pollutants.
- Ozonation is a common water treatment method, but byproduct formation requires careful management.
Purpose:
- To investigate the formation of bromate (BrO3-) during the ozonation of Yellow River water.
- To evaluate the effectiveness of various heterogeneous catalysts (NiO, CuO, Fe3O4, Al2O3) in minimizing BrO3- formation.
- To understand the reaction pathways of BrO3- formation and the role of hydroxyl radicals (*OH) and ozone (O3).
Summary:
- Batch reactor studies showed catalytic ozonation with NiO, CuO, Fe3O4, and Al2O3 reduced BrO3- by 34.0%, 32.8%, 29.2%, and 20.8%, respectively.
- The ratio of *OH to O3 concentration (R(ct)) decreased over time, ranging from 10^-8 to 10^-6.
- For Fe3O4 catalysis, the primary pathway involved *OH oxidation followed by O3, and 60.7% UV254 removal was achieved in 20 minutes.
Impact:
- Catalytic ozonation effectively minimizes bromate formation, a regulated drinking water contaminant.
- The process demonstrates efficient oxidation of organic matter (indicated by UV254 reduction).
- This research offers a viable strategy for enhancing water treatment safety and efficiency by controlling disinfection byproducts.
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