Treatment of Diesel-Contaminated Soil by Fenton and Persulfate Oxidation with Zero-Valent Iron

The objective of this research is to investigate Fenton and persulfate oxidation with zero-valent iron [Fe(0)] as a batch type ex-situ remediation technology for the treatment of diesel-contaminated soil. Results from batch experiments indicate that Fe(0) is a better catalyst for H2O2 and persulfate than Fe2+ for the enhancement of Fenton and persulfate oxidation in a batch system. Maximum removal was obtained after 12h when 1 and 2g of Fe(0) were added to hydrogen peroxide (250mg/L) and persulfate (250mg/L), respectively, in a soil-water system. As the amounts of Fe(0) and persulfate were increased three times at the optimal ratio, the removal of total petroleum hydrocarbon (TPH) was enhanced accordingly. More than 90% of the TPH was removed in 3h, and the treated soil met the Korean regulation level (500mg/kg) for TPH. Increased amounts of Fe(0) and hydrogen peroxide (up to 10g and 1250mg/L, respectively) also significantly enhanced degradation under the optimal conditions. The results of our study suggest that Fe(0)-assisted Fenton and persulfate oxidation in a batch reactor may be an alternative option to treat diesel-contaminated soil.