Oxidation on zerovalent iron promoted by polyoxometalate as an electron shuttle

Jaesang Lee, Jungwon Kim, Wonyong Choi

Research output: Contribution to journalArticlepeer-review

76 Citations (Scopus)

Abstract

Most studies on zerovalent iron (ZVI) were mainly focused on the reductive transformation of halo- or nitro-compounds. Oxidation reactions occurring on ZVI have been recently recognized. In this study, we demonstrate that the oxidation pathways on ZVI can be accelerated by the presence of polyoxometalate (POM: nanosized metal-oxygen cluster anion) serving as an electron shuttle. The ions, SiW12O404- and PW12O 403-, can mediate the electron transfer from the Fe 0 surface to O2 while enhancing the production of H 2O2, which subsequently initiates the OH radical-mediated oxidation through a Fenton-type reaction. The oxidation reaction was completely quenched by adding methanol as an OH radical-scavenger. On the other hand, PMO12O403- completely inhibited the oxidative degradation by irreversibly scavenging an electron and holding it. We systematically investigated the effects of iron loading, the concentration of POM, and pH on the oxidative degradation kinetics of 4-chlorophenol in the POM-mediated ZVI system. The POM-mediated oxidations on ZVI were additionally tested for 12 organic contaminants and the rates were compared. Their oxidative degradation on ZVI was mostly enhanced in the presence of POM (SiW 12O404-). The present study provides a good model system upon which the ZVI-based oxidation technologies can be successfully enhanced and modified for further developments.

Original languageEnglish
Pages (from-to)3335-3340
Number of pages6
JournalEnvironmental Science and Technology
Volume41
Issue number9
DOIs
Publication statusPublished - 2007 May 1
Externally publishedYes

ASJC Scopus subject areas

  • Chemistry(all)
  • Environmental Chemistry

Fingerprint Dive into the research topics of 'Oxidation on zerovalent iron promoted by polyoxometalate as an electron shuttle'. Together they form a unique fingerprint.

Cite this