Destruction of PCB 44 in Spiked Subsurface Soils Using Activated Persulfate Oxidation

The effectiveness of persulfate oxidation for the destruction of tetrachlorobiphenyl a representative polychlorobiphenyl (PCB), in spiked subsurface soils was evaluated in this study. Kaolin and glacial till soils were selected as representative low permeability soils; both soils were spiked with 50 mg PCB per dry kilogram of soil. Activation of persulfate oxidation was necessary to achieve effective destruction of PCBs in soils. As persulfate oxidation activators, temperature and high pH were used in order to maximize PCB destruction. In addition, the effect of oxidant dose and reaction time was investigated. The optimal dose for persulfate was found to be 30% for maximum oxidation. The persulfate activation with temperature of 45A degrees C was superior to persulfate activation with high pH (pH 12), where higher PCB destructions were observed for kaolin and glacial till soils. PCB destruction increased with reaction time, where maximum degradation was achieved after 7 days. The highest PCB destruction was achieved with temperature activation at 45A degrees C using a dosage of 30% persulfate at pH 12 for kaolin and glacial till soils after 7 days.