Oxidant Comparison Matrix

51 Everett Drive ? West Windsor, NJ 08550 ? (617) 964-0945 ? (609) 275-8500 ? www.insituoxidation.comIn- Situ Oxidative Technologies, Inc.COMPARISON OF OXIDANTSCOMPARISON OF OXIDANTSPROPERTY SODIUM/POTASSIUM ACTIVATED MODIFIED TRADITIONALPERMANGANATE SODIUM PERSULFATE FENTON’S REAGENT FENTON’S REAGENTTreatmentof COCsHalf life in hoursSlight precipitation of iron,whichwill be adsorbedbysoilmatrix. Permeability isnot significantly affected.Can treat both chlorinatedalkenesandalkaneseffectively. Also effectivewith awide rangeofpetroleumhydrocarbons,carbon tetrachloride,chloroformand1,4-dioxane.Very effective at desorbingsoil-boundcontaminants.Gooddue to stabilizedperoxideandchelatedironcatalysts.Effective for aqueousphasecontaminants.Also, effective in treatingsoil-boundcontaminantsbecauseof theabilityto desorbanddestroycontaminants.Similar or cheaper thanKMnO4 andpersulfatedependingon theNOD.Free radicals includinghydroxyl and superoxideradicals are produced.Gas formationoccurs in theformofO2, CO2, andH2O.Modified Fenton’s canfunctionover abroadpHrange (i.e. pH2-10).Half life inminutesWill precipitate excessdarkbrown ironhyrdoxide,whichmaycause iron foulingand reduce subsurfacepermeability.Can treat both chlorinatedalkenesandalkaneseffectively. Also effectivewith awide rangeofpetroleumhydrocarbons.Not effectivewith carbontetrachlorideor chloroform.Limiteddue to poorgenerationof superoxideradicals.Poor due to immediatebufferingof acidic pHbynative soils and ironprecipitation.Effective for aqueousphase,but has limitedeffectivenesswith soil-boundcontaminanttreatment due to limitedability to desorbcontaminants. Thismayresult in subsequentrebound in groundwaterconcentrations.Similar tomodified Fenton’s.Similar or cheaper thanKMnO4 andpersulfatedependingon theNOD.Hydroxyl radicals areproduced.Moreaggressive gasformationoccurs in the formofO2, CO2, andH2O,whichcan result in explosiveconditionsRequires acidic pH(i.e. pH£ 3.5). Theadditionof acid in the sub-surfaceoften results in anexothermic reaction.Half life in daysWill formblackMnO2precipitate,whichmayreduce subsurfacepermeability.Can treat chlorinatedalkenes suchasTCEeffectively but isineffectivewithchlorinatedalkanes suchasTCA.Also, ineffectivewith benzeneandchlorobenzene.LimitedGoodEffective in groundwaterphasebut has limitedeffectivenesswithsoil-boundcontaminanttreatment due to inabilityto desorbcontaminants.Thismay result insubsequent rebound ingroundwater concentra-tions after purple/pinkcolor disappears.Similar ormoreexpensivewhencompared tomodified Fenton’s if usedasKMnO4 dependingontheNOD.Moreexpensiveif usedasNaMnO4.None. Contaminantdestructionoccurs viadirect oxidation.Nonenoticeable.Effective at naturalsubsurfacepH(i.e. pH5-8).StabilityPrecipitationHalf life in hours to daysSlight precipitation of iron,when ironactivatedpersulfate is used,whichwill be adsorbedby soilmatrix. Permeability is notsignificantly affected.Can treat chlorinatedalkeneseffectively. It hasbeen reported to bemoderately effectivewithchlorinatedalkanes.Persulfatemaybecombinedwith Fenton’s reagent forcarbon tetrachlorideandchloroform treatment.LimitedGood for chelated ironactivatedpersulfate.Poor for alkalineactivatedpersulfate dueto immediate pHbufferingbynative soils.Effective in groundwaterphasebut has limitedeffectivenesswithsoil-boundcontaminanttreatment due to inabilityto desorbcontaminants.Thismay result insubsequent rebound ingroundwater concentrationsafter residual persulfateis decomposed.Moreexpensivewhencompared to Fenton’sreagent orKMnO4 butless expensivecomparedtoNaMnO4.Sulfate free radicals areproduced.Nonenoticeable.Native subsurfacepH islowereddue to lowpHofpersulfate. At highpH(i.e. pH>10), alkaline activa-tion of persulfatemayoccur.DesorptionAbilityRadialDistributionMatrixTreatmentTreatmentCostFree RadicalChemistryReaction offgases duringinjectionsReaction pH