Journal of Nanoparticle Research

, Volume 12, Issue 6, pp 2057–2068

Reduction of Se(VI) to Se(-II) by zerovalent iron nanoparticle suspensions

  • Jovilynn T. Olegario
  • Nay Yee
  • Marissa Miller
  • John Sczepaniak
  • Bruce Manning
Research Paper

DOI: 10.1007/s11051-009-9764-1

Cite this article as:
Olegario, J.T., Yee, N., Miller, M. et al. J Nanopart Res (2010) 12: 2057. doi:10.1007/s11051-009-9764-1

Abstract

The reaction of selenate (Se(VI)) with zerovalent iron nanoparticles (nano Fe0) was studied using both conventional batch equilibrium and X-ray spectroscopic techniques. Nano Fe0 has a high uptake capacity for removal of dissolved Se(VI) reaching concentrations as high as 0.10 Se:Fe molar ratio in the solid product mixture. Kinetic studies of the Se(VI) uptake reaction in batch experiments showed an initial reaction rate (0–30 min) of 0.0364 min−1 which was four times greater than conventional Fe0 powder. Analysis of the oxidation state of Se in the solid products by X-ray absorption near edge structure (XANES) spectroscopy showed evidence for the reduction of Se(VI) to insoluble selenide (Se(-II)) species. Structural analysis of the product by extended X-ray absorption fine structure (EXAFS) spectroscopy suggested that Se(-II) was associated with nano Fe0 oxidation products as a poorly ordered iron selenide (FeSe) compound. The fitted first shell Se–Fe interatomic distance of 2.402 (±0.004) Å matched closely with previous studies of the products of Se(IV)-treated Fe(II)-clays and zero-valent iron/iron carbide (Fe/Fe3C). The poorly ordered FeSe product was associated with Fe0 corrosion product phases such as crystalline magnetite (Fe3O4) and Fe(III) oxyhydroxide. The results of this investigation suggest that nano Fe0 is a strong reducing agent capable of efficient reduction of soluble Se oxyanions to insoluble Se(-II).

Keywords

Fe nanoparticlesReductionSelenium(VI)Selenium(-II)SEMEXAFSSoilsRadioactive waste

Copyright information

© Springer Science+Business Media B.V. 2009

Authors and Affiliations

  • Jovilynn T. Olegario
    • 1
  • Nay Yee
    • 1
  • Marissa Miller
    • 1
  • John Sczepaniak
    • 1
  • Bruce Manning
    • 1
  1. 1.Department of Chemistry and BiochemistrySan Francisco State UniversitySan FranciscoUSA