title: Modified Fenton oxidation of polycyclic aromatic hydrocarbon (PAH)-contaminated soils and the potential of bioremediation as post-treatment.
abstract: This work focuses on the remediation of polycyclic aromatic hydrocarbon (PAH)-contaminated soil using modified Fenton (MF) treatment coupled with a novel chelating agent (CA), a more effective technique among currently available technologies. The performance of MF treatment to promote PAH oxidation in artificially contaminated soil was investigated in a packed column with a hydrogen peroxide (H(2)O(2)) delivery system simulating in-situ soil flushing which is more representative of field conditions. The effectiveness of process parameters H(2)O(2)/soil, Fe(3+)/soil, CA/soil weight ratios and reaction time were studied using a 2(4) three level factorial design experiments. An optimised operating condition of the MF treatment was observed at H(2)O(2)/soil 0.05, Fe(3+)/soil 0.025, CA/soil 0.04 and 3h reaction time with 79.42% and 68.08% PAH removals attainable for the upper and lower parts of the soil column respectively. The effects of natural attenuation and biostimulation process as post-treatment in the remediation of the PAH-contaminated soil were also studied. In all cases, 3-aromatic ring PAH (phenanthrene) was more readily degraded than 4-aromatic ring PAH (fluoranthene) regardless of the bioremediation approach. The results revealed that both natural attenuation and biostimulation could offer remarkable enhancement of up to 6.34% and 9.38% in PAH removals respectively after 8 weeks of incubation period. Overall, the results demonstrated that combined inorganic CA-enhanced MF treatment and bioremediation serves as a suitable strategy to enhance soil quality particularly to remediate soils heavily contaminated with mixtures of PAHs.
authors.affiliation: Department of Chemical and Environmental Engineering, The University of Nottingham Malaysia Campus, Jalan Broga, 43500 Semenyih, Selangor Darul Ehsan, Malaysia.
authors.lastname: Venny
authors.forename: Suyin
authors.initials: S
authors.lastname: Gan
authors.forename: Hoon Kiat
authors.initials: HK
authors.lastname: Ng
mesh_terms: D001673:Biodegradation, Environmental; D002614:Chelating Agents / Q000737:chemistry*; D002849:Chromatography, Gas; D011756:Diphosphates / Q000737:chemistry*; D005449:Fluorenes / Q000378:metabolism*; D006861:Hydrogen Peroxide / Q000737:chemistry; D007501:Iron / Q000737:chemistry; D010084:Oxidation-Reduction; D010616:Phenanthrenes / Q000378:metabolism*; D012987:Soil / Q000737:chemistry; D012989:Soil Pollutants / Q000378:metabolism*
chemical_list: D002614:Chelating Agents; D011756:Diphosphates; C045076:Fenton's reagent; D005449:Fluorenes; D010616:Phenanthrenes; D012987:Soil; D012989:Soil Pollutants; C007738:fluoranthene; C031181:phenanthrene; D006861:Hydrogen Peroxide; D007501:Iron; C003319:sodium pyrophosphate