Reductive dechlorination of chlorinated ethenes by iron metal and iron sulfide minerals

Conference · Sun Dec 31 04:00:00 EST 1995

OSTI ID:210182

Sivavec, T M; Horney, D P; Baghel, S S ^[1]

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1. GE Corporate Research and Development, Schenectady, NY (United States)

Reduced forms of iron and sulfur, such as Fe(II), iron(II) sulfide and hydrogen sulfide, are abundant natural reductants in anaerobic soils and sediments. Redox reactions between these reductants and organic pollutants are often greatly accelerated in natural systems because of microbial mediation or because the electron transfer is mediated by the cycling of Fe(II)/Fe(III). For example, recent studies have shown that surface-bound, reduced iron species play the important role of electron transfer mediator in reductions promoted by iron-reducing bacteria. It has been postulated that the reduction of chlorinated hydrocarbons by iron metal may occur by a reaction of surface-bound Fe(II) at the iron metal-water interface. The surface-bound Fe(II) species at the passive oxide-water interface may serve as mediator for the transfer of electrons from Fe{sup 0} to adsorbed chlorinated hydrocarbon. Fast reduction rates for chlorinated hydrocarbons observed in this system may be attributed to the facile regeneration of reducing surface Fe(II) species due to the close proximity of the bulk reductant (Fe{sup 0}) to the electron carrier, surface-bound Fe(II). Evidence in support of this proposed mechanism is presented.

• OSTI ID: 210182
• Report Number(s): CONF-9509139--
• Country of Publication: United States
• Language: English

Related Subjects

40 CHEMISTRY
54 ENVIRONMENTAL SCIENCES
CHLORINATED ALIPHATIC HYDROCARBONS
DECHLORINATION
ELECTRON TRANSFER
IRON
IRON SULFIDES
ORGANIC WASTES
REDUCTION
WASTE PROCESSING