|
Fenton's Reagent
Hydrogen peroxide, which
can be delivered at depth using lance permeation or soil mixing techniques or
injected water amendments, is an effective oxidizing agent. However, to achieve
the desired contaminant reductions in a reasonable time, a metal catalyst is
often required. Iron is most commonly used, and, when mixed with hydrogen
peroxide, the catalyst is known as Fenton’s reagent.
The process is well documented for producing hydroxyl
radicals by the reaction of hydrogen peroxide and ferrous iron (Fe+2 ). The hydroxyl radicals (OHC) serve as very powerful,
effective, and nonspecific oxidizing agents, second only to fluorine in
oxidizing power. Many reactions occur during the oxidation of a contaminant,
and either ferrous or ferric iron can react with the peroxide to produce
oxidizing radicals. The usefulness of Fenton’s reagent may be limited by low
soil permeability, incomplete site delineation, subsurface heterogeneities, and
highly alkaline soils where carbonate ions are free radical (hydroxyl)
scavengers.
|
