title: Enhanced abiotic reduction of Cr(VI) in a soil slurry system by natural biomaterial addition.
abstract: Among various plant-based natural biomaterials, pine bark was chosen as an efficient biomaterial capable of removing toxic Cr(VI) from aqueous solution. XPS spectra indicated that Cr(VI) was abiotically reduced to Cr(III) in both liquid and solid phases. The Cr(VI)-reducing capacity of pine bark was determined as 545 (+/-1.3)mg-Cr(VI)g(-1) of it, which was 8.7 times higher than that of a common chemical Cr(VI)-reductant, FeSO4 x 7H2O. Because pine bark could completely reduce toxic Cr(VI) to less toxic or nontoxic Cr(III) even at neutral pH, it was used as an organic reductant to remediate Cr(VI)-contaminated soil in this study. Soil slurry system using a bottle roller was applied to ex situ slurry-phase remediation experiments. In the soil slurry system, pine bark completely reduced Cr(VI) to Cr(III) and adsorbed the reduced-Cr(III) on its surface. Abiotic remediation rate of Cr(VI)-contaminated soil increased with the increase of pine bark dosage and with the decreases of Cr(VI) and water contents. In conclusion, pine bark can be used to remediate Cr(VI)-contaminated soil efficiently and environmentally friendly.
authors.affiliation: Advanced Environmental Biotechnology Research Center, Department of Chemical Engineering, School of Environmental Science and Engineering, Pohang University of Science and Technology, San 31, Hyoja-dong, Pohang 790-784, South Korea.
authors.forename: Donghee
authors.initials: D
authors.lastname: Park
authors.forename: Chi Kyu
authors.initials: CK
authors.lastname: Ahn
authors.forename: Young Mi
authors.initials: YM
authors.lastname: Kim
authors.forename: Yeoung-Sang
authors.initials: YS
authors.lastname: Yun
authors.forename: Jong Moon
authors.initials: JM
authors.lastname: Park
mesh_terms: D002857:Chromium / Q000737:chemistry*; D003124:Colorimetry; D052918:Environmental Restoration and Remediation; D006863:Hydrogen-Ion Concentration; D010084:Oxidation-Reduction; D028223:Pinus / Q000737:chemistry*; D024301:Plant Bark / Q000737:chemistry; D012987:Soil / Q000032:analysis*; D012989:Soil Pollutants / Q000032:analysis*; D013052:Spectrometry, X-Ray Emission; D014867:Water / Q000032:analysis
chemical_list: D012987:Soil; D012989:Soil Pollutants; D014867:Water; D002857:Chromium