Tuesday, November 6, 2007
231-12

Mechanism and Capacity of Zerovalent Irons to Remediate Cr(VI) Contaminated Water.

Jae E. Yang, Jong-Sung Kim, Yong Sik Ok, and Dong Kook Kim. Department of Biological Environment, Kangwon National University, 192-1 Hyoja 2 Dong, Chuncheon, 200-701, South Korea

We conducted this research to evaluate possible mechanism(s) and capacity of zerovalent irons to remediate Cr(VI) in an aqueous solution. Advanced equipments including SEM-EDS, XRD and XPS were adopted to determine surface properties of zerovalent irons, and Fe-Cr products. Luminescent bacteria, Photobacterium Phosphoreum, was used to determine the efficiency of zerovalent irons for Cr(VI) reduction. The Cr(VI) in water was reduced to Cr(III) when Fe0 was oxidized to Fe(II,III) showing the presence of Fe2O3, (Fe-Cr)2O3 and FeOOH. The SEM-EDS analysis showed that zerovalent irons with high reducing capacity was more subject to changes in surface properties due to the ionization. The Cr and Fe in the precipitates subsisted exclusively in the Cr(III) or Fe(III) states with the respective forms of Cr(OH)3 or Cr2O3 and FeOOH or Fe2O3. Electrons produced from zerovalent iron oxidation reduced Cr(VI) to Cr(III) thus resultantly Cr(III) precipitated or co-precipitated with Fe(III) to form Fe(III)-Cr(III) hydroxide or Fe(III)-Cr(III) oxyhydroxide. Toxicity of water reacted with ZVI was also significantly reduced compared to that of the untreated water.

Back to Characterization of Contaminated Systems: I
Back to S11 Soils & Environmental Quality

Back to The ASA-CSSA-SSSA International Annual Meetings (November 4-8, 2007)