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Chemiluminescence-based Assays for Detection of Nitric Oxide and its Derivatives from Autoxidation and Nitrosated Compounds
Published on: February 16, 2022
Reduced iron induced nitric oxide and nitrous oxide emission
Marlies J Kampschreur1, Robbert Kleerebezem, Weren W J M de Vet
1Delft University of Technology, Department of Biotechnology, Delft, The Netherlands. mkampschreur@aaenmaas.nl
Water Research
|September 24, 2011
Summary
Chemical processes contribute to greenhouse gas nitrous oxide (N2O) emissions in water treatment. This study shows ferrous iron (Fe(II)) chemically reduces nitrite, forming nitric oxide (NO) and N2O, impacting water treatment emissions.
Area of Science:
- Environmental Chemistry
- Water Treatment Technologies
- Greenhouse Gas Emissions
Background:
- Nitrous oxide (N2O) formation in water treatment is primarily viewed as biological.
- Emerging evidence suggests chemical pathways also contribute to N2O emissions.
Purpose of the Study:
- To investigate the chemical reduction of nitrite by ferrous iron (Fe(II)) as a source of nitric oxide (NO) and N2O.
- To understand the kinetics and influencing factors of these chemical reactions.
Main Methods:
- Laboratory-scale experiments were conducted to study nitrite and NO reduction coupled to Fe(II) oxidation.
- Measurements were taken at varying pH, nitrite, and iron concentrations.
- Continuous monitoring of NO and N2O emissions was performed.
Main Results:
- Nitrite reduction by Fe(II) follows first-order kinetics with respect to nitrite concentration.
- NO reduction rate appears dependent on reactive surface availability and Fe(II) sorption.
- Distinct kinetics were observed for nitrite and NO reduction.
Conclusions:
- Chemical reduction of nitrite by Fe(II) is a significant pathway for NO and N2O formation in water treatment.
- This chemical pathway plays a role in various environmental settings involving iron oxidation and nitrite presence.
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