Addition of Hydrogen Peroxide to Groundwater with Natural Iron Induces Water Disinfection by Photo-Fenton at Circumneutral pH and other Photochemical Events
| Autor: | Janeth Sanabria, Héctor M. Gutiérrez-Zapata, John J. Alvear-Daza, Julián A. Rengifo-Herrera |
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| Rok vydání: | 2017 |
| Předmět: |
Iron
Radical Carbonates 02 engineering and technology 010501 environmental sciences medicine.disease_cause 01 natural sciences Biochemistry Phosphates Fluorides chemistry.chemical_compound medicine Physical and Theoretical Chemistry Turbidity Hydrogen peroxide Groundwater Escherichia coli 0105 earth and related environmental sciences chemistry.chemical_classification Reactive oxygen species Escherichia coli K12 Hydrogen Peroxide General Medicine Hydrogen-Ion Concentration Photochemical Processes 021001 nanoscience & nanotechnology Phosphate Disinfection chemistry Environmental chemistry Microscopy Electron Scanning Sunlight Carbonate 0210 nano-technology Fluoride |
| Zdroj: | Photochemistry and Photobiology. 93:1224-1231 |
| ISSN: | 0031-8655 |
| DOI: | 10.1111/php.12779 |
| Popis: | Samples of natural groundwater (with low turbidity, neutral pH and 0.3 mg L−1 iron concentration) inoculated with Escherichia coli K-12, were exposed to simulated solar light both in the presence and absence 10 mg L−1 of H2O2. Results demonstrated that the viability of E. coli (by DVC-FISH) was grounded to zero after 360 min of irradiation. This abatement could be caused by the oxidative stress induced by •OH radicals or another photo-induced reactive oxygen species. Two 23 factorial experimental designs enabled the evaluation of the effects of chemical factors on the inactivation of E. coli. The first experimental design considered the pH, iron and H2O2, while the second evaluated the ions fluoride, carbonate and phosphate found in groundwater. pH was found to play a key role in the inactivation of E. coli. The best reduction in viability was obtained at the lower pH (6.75), while a non-significant effect was observed when iron or H2O2 concentrations were raised. At higher concentrations, anions such as carbonate and phosphate, negatively affected the E. coli abatement. However, a higher concentration of fluoride accelerated it. In all experiments, the pH was observed to rise to values higher than 8.0 units after 360 min of treatment. This article is protected by copyright. All rights reserved. |
| Databáze: | OpenAIRE |
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