Degradation of hexachloroethane by Fenton's reagents.

The effect of hydrogen peroxide (H2O2) concentrations on the degradation of hexachloroethane (HCA) in the absence and the presence of tetrachloroethene (PCE) by Fenton's reagent was investigated at pH 3 with 1 mM iron(II) and H2O2 concentrations ranging from 0.01 M to 2 M. HCA degradation in the absence of PCE increased with increasing H2O2 concentration between 0.2 M and 2 M. In the presence of PCE, HCA degradation was similar to that in the absence of PCE for H2O2 concentration up to 1 M, but significantly higher for 2 M H2O2. We propose that this increase is a result of elevated reductant radicals when PCE is present. This study highlights the need for further investigation into the degradation of contaminant mixtures at higher H2O2 concentrations.