| Abstract
| - To provide a more complete understanding of the kineticsof in situ chemical oxidation (ISCO) with permanganate(MnO4-), we measured the kinetics of oxidation of 24contaminantsmany for which data were not previouslyavailable. The new data reported here were determined usingan efficient method based on continuous measurementof the MnO4- concentration by absorbance spectrometry.Under these conditions, the kinetics were found to be first-order with respect to both contaminant and MnO4-concentrations, from which second-order rate constants(k‘ ‘) were readily obtained. Emerging contaminants for whichk‘ ‘ was determined (at 25 °C and pH 7) include 1,4-dioxane (4.2 × 10-5 M-1 s-1), methyl t-butyl ether (MTBE)(1.0 × 10-4 M-1 s-1), and methyl ethyl ketone (MEK) (9.1× 10-5 M-1 s-1). Contaminants such as 2,4,6-trinitrotoluene(TNT), the pesticides aldicarb and dichlorvos, and manysubstituted phenols are oxidized with rate constantscomparable to tetrachloroethene (PCE) and trichloroethene(TCE) (i.e., 0.03−1 M-1 s-1) and therefore are goodcandidates for remediation with MnO4- in the field. Thereare severalsometimes competingmechanisms bywhich MnO4- oxidizes contaminants, including addition todouble bonds, abstraction of hydrogen or hydride, andelectron transfer.
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