title: Application of biosurfactants and periodic voltage gradient for enhanced electrokinetic remediation of metals and PAHs in dredged marine sediments.
abstract: Dredged harbor sediment co-contaminated by heavy metals and polycyclic aromatic hydrocarbons (PAHs) was subjected to enhanced electrokinetic treatments, using a mixture of a chelating agent (citric acid CA) and a surfactant as additives in the processing fluids. We tested various operating conditions (at 1 V cm(-1)): different CA concentrations, applying a periodic voltage gradient, pre-conditioning the sediment with the additives, and replacing the synthetic surfactant Tween 20 (TW20) by biosurfactants. Increasing the CA concentration was favorable for both metal and PAH removal. Applying a periodic voltage gradient associated to a low concentration of CA and TW20 provided the best results for Zn, Cd and Pb removal and also for removal of the 16 priority PAHs. Promising results were obtained with solutions containing rhamnolipids (0.028%) and a viscosin-like biosurfactant produced by Pseudomonas fluorescens Pfa7B (0.025%), associated to a periodic voltage gradient. Although the rhamnolipid and the viscosin-like compounds involved a higher electrical current than TW20, metals were less removed from the sediment. The electroosmotic flow was lower when we used biosurfactants, hence a less effective effect on PAH removal.
authors: Laboratoire Ondes et Milieux Complexes, UMR CNRS 6294, Université du Havre, 53 rue de Prony, 76600 le Havre, France. Electronic address: mohamed-tahar.ammami@univ-lehavre.fr.
authors: M T
authors: MT
authors: Ammami
authors: Laboratoire COBRA UMR CNRS 6014, Université de Rouen, 55 rue Saint Germain, 27000 Evreux, France. Electronic address: florence.koltalo@univ-rouen.fr.
authors: F
authors: F
authors: Portet-Koltalo
authors: Laboratoire Ondes et Milieux Complexes, UMR CNRS 6294, Université du Havre, 53 rue de Prony, 76600 le Havre, France. Electronic address: ahmed.benamar@univ-lehavre.fr.
authors: A
authors: A
authors: Benamar
authors: Laboratoire de microbiologie - signaux et micro-environnement, EA 4312, Université de Rouen, 55 rue Saint Germain, 27000 Evreux, France. Electronic address: cecile.poc@univ-rouen.fr.
authors: C
authors: C
authors: Duclairoir-Poc
authors: Laboratoire Ondes et Milieux Complexes, UMR CNRS 6294, Université du Havre, 53 rue de Prony, 76600 le Havre, France. Electronic address: huaquing.wang@univ-lehavre.fr.
authors: H
authors: H
authors: Wang
authors: Laboratoire COBRA UMR CNRS 6014, Université de Rouen, 55 rue Saint Germain, 27000 Evreux, France. Electronic address: franck.lederf@univ-rouen.fr.
authors: F
authors: F
authors: Le Derf
mesh_terms: D002614:Chelating Agents / Q000737:chemistry*; D004560:Electricity; D052918:Environmental Restoration and Remediation / Q000379:methods*; D019015:Geologic Sediments / Q000737:chemistry; D019216:Metals, Heavy / Q000737:chemistry*; D011084:Polycyclic Aromatic Hydrocarbons / Q000737:chemistry*; D011136:Polysorbates / Q000737:chemistry; D011551:Pseudomonas fluorescens / Q000378:metabolism; D013501:Surface-Active Agents / Q000737:chemistry; D014874:Water Pollutants, Chemical / Q000737:chemistry*
chemical_list: D002614:Chelating Agents; D019216:Metals, Heavy; D011084:Polycyclic Aromatic Hydrocarbons; D011136:Polysorbates; D013501:Surface-Active Agents; D014874:Water Pollutants, Chemical
keywords: Biosurfactants; Electrokinetic remediation; Heavy metals; Periodic voltage; Polycyclic aromatic compounds