Fractionation of Cd and Zn in Cd-contaminated soils amended by sugarcane waste products from an ethanol production plant
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SOILS, SEC 3 • REMEDIATION AND MANAGEMENT OF CONTAMINATED OR DEGRADED LANDS • RESEARCH ARTICLE
Fractionation of Cd and Zn in Cd-contaminated soils amended by sugarcane waste products from an ethanol production plant Pensiri Akkajit & Thomas DeSutter & Chantra Tongcumpou
Received: 1 January 2013 / Accepted: 24 March 2013 / Published online: 10 April 2013 # Springer-Verlag Berlin Heidelberg 2013
Abstract Purpose Sugarcane waste products (boiler ash, filter cake, and vinasse) from an ethanol production plant were used as soil amendments by adding 3 % (w/w) in single and/or in combination, with a research focus towards stabilization of cadmium (Cd) and zinc (Zn) in contaminated soils. The objective of this laboratory study was to evaluate the effects of adding these sugarcane waste products on bioavailability of Cd and Zn over time (aging) in Cd- and Zn-contaminated agricultural soils of Thailand. Materials and methods Two agricultural contaminated soils of low (BCR3 for LCdS and HCdS, respectively.
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Cd fractionation
Fig. 2 Cd fractionation change over time (T0, T14, T28, T56, and T84) by different sugarcane waste products amended into the high Cd-contaminated soil (H1, H2, H3, H4, H5, H6, H7, and HC)
J Soils Sediments (2013) 13:1057–1068
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to be slightly decreased (*pBCR3 >BCR4. Higher Cd extractability in the exchangeable (BCR1) and reducible (BCR2) fractions suggested that Cd can be easily mobilized and potentially bioavailable. Portions of metals in exchangeable fractions are weakly adsorbed to the colloidal and particulate material of the soil, and susceptible to pH changes (Filgueiras et al. 2002; Gleyzes et al. 2002). Relatively high Cd in the reducible fraction may be related to formation of Fe/Mn oxide and hydroxides whereby precipitation and coprecipitation act as important metal sinks that would be released and/or mobilized by reduced and anoxic conditions in the environment (Hlavay et al. 2004; Purushothaman and Chakrapani 2007; Manskinen et al. 2011). Therefore, presence of significant amounts of Cd in these two fractions (BCR1 + 2) (the highest of 97.4 % in L1 of LCdS and
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Zn fractionation
Zn fractionation
Fig. 4 Zn fractionation change over time (T0, T14, T28, T56, and T84) by different sugarcane waste products amended into the high Cd-contaminated soil (H1, H2, H3, H4, H5, H6, H7, and HC)
J Soils Sediments (2013) 13:1057–1068
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