The scope of this study was to determine techniques to remediate trichloroethylene contamination under different environmental conditions, media and in co-existence with chromium. The specific objectives were focused on the oxidation of trichloroethylene (TCE) in soil and aqueous media using both unmodified KMnO4 particles and poly (methyl methacrylate), PMMA encapsulated KMnO4 in the presence and absence of hexavalent chromium, Cr(VI). Molar ratios (p-values) of KMnO4 to TCE were used as a determining factor in the TCE oxidation process. p-values of 2, 5 and 10 were investigated in aqueous media and an approximately 0.5 M-1·s-1 rate constant was obtained using unmodified KMnO4 in aqueous system. The extent of oxidation did not change with TCE concentration. In soil system, TCE oxidation requires a large amount of KMnO4 to produce similar results as in aqueous system. pH experiments indicate that except at high alkaline condition, pH does not impact the extent of TCE oxidation. Also, the presence of Cr(VI) did not hinder TCE oxidation by KMnO4. Using controlled release application, the rate of TCE oxidation was reduced by PMMA encapsulated KMnO4. Comparative study indicated an expectedly slow rate of TCE degradation using modified KMnO4 but similar overall extent of oxidation for both modified and unmodified KMnO4. The application of the encapsulated matrix yielded 88% ± 3% TCE oxidation and a simultaneous 81% ± 2.1% Cr(VI) reduction by ferrous ion in the same system.
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