Different fate of Pb and Cu at varied peroxide concentrations during the modified Fenton reaction in soil and its effect on the degradation of 2,4-dinitrotoluene

BACKGROUND Military areas such as firing ranges have serious contamination problems due to both heavy metals and nitroaromatic compounds (NACs). The feasibility of modified Fenton reactions for remediation of NACs is studied by investigating the fate of lead (Pb) and copper (Cu) during the modified Fenton reactions and its effect on the degradation of 2,4‐dinitrotoluene (2,4‐DNT) in soils at various hydrogen peroxide (H2O2) concentrations. RESULTS During the reactions, the Pb fate was not affected at ≤0.2 mol L−1 H2O2, but final aqueous phase Pb was higher in the samples than in the controls at >0.2 mol L−1 H2O2. These changes in the Pb fate resulted in interference with 2,4‐DNT degradation at ≥0.2 mol L−1 H2O2. Similarly, aqueous phase Cu was higher in samples with >0.2 mol L−1 H2O2 than in the controls; however, unlike Pb, these changes did not have adverse effects on 2,4‐DNT degradation. CONCLUSION The different effects of heavy metals such as Pb and Cu on 2,4‐DNT degradation in soils during modified Fenton reactions need to be understood to optimize 2,4‐DNT degradation performance. The results help to advance the Fenton reaction applications for the remediation of soils contaminated with Pb or Cu and 2,4‐DNT mixtures. © 2012 Society of Chemical Industry