Molecular-Scale Speciation of Zn and Ni in Soil Ferromanganese Nodules from Loess Soils of the Mississippi Basin
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- 作者：Alain Manceau ; Nobumichi Tamura ; Richard S. Celestre ; Alastair A. MacDowell ; Nicolas Geoffroy ; Garrison Sposito ; and Howard A. Padmore
- 刊名：Environmental Science & Technology
- 出版年：2003
- 出版时间：January 1, 2003
- 年：2003
- 卷：37
- 期：1
- 页码：75 - 80
- 全文大小：827K
- 年卷期：v.37,no.1(January 1, 2003)
- ISSN：1520-5851
文摘
Determining how environmentally important trace metalsare sequestered in soils at the molecular scale is critical todeveloping a solid scientific basis for maintaining soilquality and formulating effective remediation strategies.The speciation of Zn and Ni in ferromanganese nodules fromloess soils of the Mississippi Basin was determined by asynergistic use of three noninvasive synchrotron-basedtechniques: X-ray microfluorescence (
XRF), X-raymicrodiffraction (XRD), and extended X-ray absorptionfine structure spectroscopy (EXAFS). We show that Ni isdistributed between goethite (
-FeOOH) and the manganeseoxide lithiophorite, whereas Zn is bound to goethite,lithiophorite, phyllosilicates, and the manganese oxidebirnessite. The selective association of Ni with only ironand manganese oxides is an explanation for its higherpartitioning in nodules over the soil clay matrix reportedfrom soils worldwide. This could also explain the observedenrichment of Ni in oceanic manganese nodules. Thecombination of these three techniques provides a newmethod for determining trace metal speciation in both naturaland contaminated environmental materials.
XRF), X-raymicrodiffraction (XRD), and extended X-ray absorptionfine structure spectroscopy (EXAFS). We show that Ni isdistributed between goethite (-FeOOH) and the manganeseoxide lithiophorite, whereas Zn is bound to goethite,lithiophorite, phyllosilicates, and the manganese oxidebirnessite. The selective association of Ni with only ironand manganese oxides is an explanation for its higherpartitioning in nodules over the soil clay matrix reportedfrom soils worldwide. This could also explain the observedenrichment of Ni in oceanic manganese nodules. Thecombination of these three techniques provides a newmethod for determining trace metal speciation in both naturaland contaminated environmental materials.