Inclusion of vegetable oils in Fenton's chemistry for remediation of PAH-contaminated soils.
Pre-treatment with vegetable oils prior to treatment with Fenton's reagent led to increased oxidation by the latter of polycyclic aromatic hydrocarbons (PAHs) in a pair of model manufactured gas plant soils. This effect was frequently most pronounced in the cases of high-molecular-weight (HMW) PAH species, indicating a preferential "targeting" of oxidative equivalents toward these compounds. In both cases, addition of oils--either corn oil containing unsaturated lipids or palm kernal oil (PKO) comprised primarily of saturated fats--at the 5% dosage was required; supplementation with 1% oil apparently did not sufficiently facilitate PAH desorption and mass-transfer to have a notable effect on degradation efficiency. In PKO-supplemented reactions, replacement of H2O2 with calcium peroxide (CaO2) further increased the extent of PAH removal. Again, this was most pronounced in the cases of several HMW PAHs; among a suite of four 5- and 6-ring PAH (benzo[a]pyrene, dibenz[a, h]anthracene, benzo[g, h, i]perylene and indeno[c, d]pyrene), average removal efficiency increased from 5% in PKO-supplemented reactions in which H2O2 served as the oxidant, compared to 44% in CaO2-containing reactions. This last finding is consistent with other reports which have indicated that slower-release oxidants are better suited to degradation of contaminants which, despite vegetable oil treatment, remain soil-sorbed.
Bogan
Bill W
BW
Gas Technology Institute, 1700 South Mt. Prospect Road, Des Plaines, IL 60018, USA. bill.bogan@gastechnology.org
Trbovic
Vesna
V
Paterek
J Robert
JR
D002617:Chemical Industry; D006861:Hydrogen Peroxide / Q000737:chemistry*; D057927:Hydrophobic and Hydrophilic Interactions; D007501:Iron / Q000737:chemistry*; D008970:Molecular Weight; D010084:Oxidation-Reduction; D010545:Peroxides / Q000737:chemistry; D010938:Plant Oils / Q000737:chemistry*; D011084:Polycyclic Aromatic Hydrocarbons / Q000737:chemistry*; D012989:Soil Pollutants / Q000032:analysis*; D012995:Solubility
C045076:Fenton's reagent; D010545:Peroxides; D010938:Plant Oils; D011084:Polycyclic Aromatic Hydrocarbons; D012989:Soil Pollutants; C403632:calcium peroxide; D006861:Hydrogen Peroxide; D007501:Iron