Complete Reduction of TNT and Other (Poly)nitroaromatic Compounds under Iron-Reducing Subsurface Conditions
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- 作者：Thomas B. Hofstetter ; Cornelis G. Heijman ; Stefan B. Haderlein ; Christof Holliger ; and René ; P. Schwarzenbach
- 刊名：Environmental Science & Technology
- 出版年：1999
- 出版时间：May 1, 1999
- 年：1999
- 卷：33
- 期：9
- 页码：1479 - 1487
- 全文大小：207K
- 年卷期：v.33,no.9(May 1, 1999)
- ISSN：1520-5851
文摘
Contamination of soils and aquifers with (poly)nitroaromaticcompounds ((P)NACs) is a widespread problem. Thiswork demonstrates that (P)NACs such as the explosive 2,4,6-trinitrotoluene (TNT) can be completely reduced to thecorresponding aromatic polyamines by Fe(II) present at thesurface of Fe(III)(hydr)oxides or, less efficiently, byhydroquinone moieties of (natural) organic matter in thepresence of H2S. The reduction kinetics of (P)NACs wereinvestigated in sterile batch systems as well as incolumns containing either FeOOH-coated sand and a pureculture of the iron-reducing bacterium Geobactermetallireducens or ferrogenic consortia in aquifersediments. The relative reactivities as well as thecompetition behavior of (P)NACs in batch and columnsystems, respectively, correlated well with their one-electronreduction potentials, 
', which we determined for TNTand its aminonitrotoluene transformation products. A similarreactivity pattern of (P)NACs was found irrespective ofthe processes that (re)generated the surface-bound Fe(II),i.e., adsorption of Fe(II) from aqueous solution or microbialreduction of Fe(III)(hydr)oxides. The apparent stability of thetoxic arylamine products under ferrogenic conditionsmay compromise intrinsic attenuation as an acceptableremediation option for (P)NAC contaminated anoxic aquifers.Iron-reducing conditions would, however, be favorableas a first step in a two-stage anaerobic/aerobic treatmentof PNAC contaminated sediments since aromaticpolyamines are biodegradable and/or bind irreversibly tothe solid matrix under oxic conditions.
', which we determined for TNTand its aminonitrotoluene transformation products. A similarreactivity pattern of (P)NACs was found irrespective ofthe processes that (re)generated the surface-bound Fe(II),i.e., adsorption of Fe(II) from aqueous solution or microbialreduction of Fe(III)(hydr)oxides. The apparent stability of thetoxic arylamine products under ferrogenic conditionsmay compromise intrinsic attenuation as an acceptableremediation option for (P)NAC contaminated anoxic aquifers.Iron-reducing conditions would, however, be favorableas a first step in a two-stage anaerobic/aerobic treatmentof PNAC contaminated sediments since aromaticpolyamines are biodegradable and/or bind irreversibly tothe solid matrix under oxic conditions.