Mechanistic Study of the ZEA Organic Pollutant Degradation System: Evidence for H2O2, HO•, and the Homogeneous Activation of O2 by FeIIEDTA
| Autor: | Alexander Blumenfeld, Derek F. Laine, I. Francis Cheng |
|---|---|
| Rok vydání: | 2008 |
| Předmět: |
Zerovalent iron
Electrolysis Chemistry Reducing agent General Chemical Engineering Reactive intermediate Inorganic chemistry chemistry.chemical_element Ethylenediaminetetraacetic acid General Chemistry Electrochemistry Oxygen Industrial and Manufacturing Engineering law.invention chemistry.chemical_compound law Hydrogen peroxide |
| Zdroj: | Industrial & Engineering Chemistry Research. 47:6502-6508 |
| ISSN: | 1520-5045 0888-5885 |
| DOI: | 10.1021/ie701676q |
| Popis: | The ZEA (zero valent iron, ethylenediaminetetraacetic acid (EDTA), and air) organic pollutant degradation system has been previously shown to degrade a variety of organic pollutants and chemical warfare agent surrogates; however, mechanistic details and reactive intermediates formed in this system have not been identified. It is hypothesized that the ZEA system produces reactive oxygen species (H2O2, HO•) by the reduction of oxygen by FeIIEDTA(aq). This hypothesis is examined through an electrochemical model of the ZEA system. A carbon basket electrode is used as the reducing agent in place of Fe(0). The FeIIIEDTA complex (0.5 mM) is electrochemically reduced to FeIIEDTA at an applied potential of −120 mV (vs Ag/AgCl) under aerobic conditions. Hydrogen peroxide was observed to form in the presence of the metal complex with a maximum concentration reaching 0.139 mM H2O2 after 3 h of electrolysis. In the absence of FeEDTA, 0.04 mM H2O2 is obtained by the direct reduction of O2 at the electrode surface. Elec... |
| Databáze: | OpenAIRE |
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