title: Decontamination of metals, pentachlorophenol, and polychlorined dibenzo-p-dioxins and dibenzofurans polluted soil in alkaline conditions using an amphoteric biosurfactant.
abstract: In this paper, flotation in acidic conditions and alkaline leaching soil washing processes were compared to decontaminate four soils with variable contamination with metals, pentachlorophenol (PCP), and polychlorodibenzo dioxins and furans (PCDD/F). The measured concentrations of the four soils prior treatment were between 50 and 250 mg/kg for As, 35 and 220mg/kg for Cr, 80 and 350mg/kg for Cu, and 2.5 and 30mg/kg for PCP. PCDD/F concentrations reached 1394, 1375, 3730, and 6289ng/kg for F1, S1, S2, and S3 soils, respectively. The tests were carried out with masses of 100g of soil (fraction 0-2 mm) in a 2 L beaker or in a 1 L flotation cell. Soil flotation in sulphuric acid for 1 h at 60 degreeC with three flotation cycles using the surfactant cocamidopropyl betaine (BW) at 1% allows the solubilization of metals and PCP with average removal yields of 85%, 51%, 90%, and 62% for As, Cr, Cu, and PCP, respectively. The alkaline leaching for 2 h at 80 degreeC solubilizes As, Cr, Cu, and PCP with average removal yields of 60%, 32%, 77%, and 87%, respectively. Tests on PCDD/F solubilization with different surfactants were carried out in combination with the alkaline leaching process. PCDD/F removal yields of 25%, 72%, 70%, and 74% for F1, S1, S2, and S3 soils, respectively, were obtained using the optimized conditions.
authors.affiliation: Institut national de la recherche scientifique (Centre Eau, Terre et Environnement), Universiti du Qudbec, 490 rue de la Couronne, Québec, QC, Canada GIK 9A9.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Reynier
authors.affiliation: Institut national de la recherche scientifique (Centre Eau, Terre et Environnement), Universiti du Qudbec, 490 rue de la Couronne, Québec, QC, Canada GIK 9A9.
authors.forename: Jean-François
authors.initials: JF
authors.lastname: Blais
authors.affiliation: Institut national de la recherche scientifique (Centre Eau, Terre et Environnement), Universiti du Qudbec, 490 rue de la Couronne, Québec, QC, Canada GIK 9A9.
authors.forename: Guy
authors.initials: G
authors.lastname: Mercier
authors.affiliation: lnstitut de recherche d'Hydro-Québec (IREQ), 1800, boul. Lionel-Boulet, Varennes, QC, Canada J3X IS1.
authors.forename: Simon
authors.initials: S
authors.lastname: Besner
mesh_terms: D000468:Alkalies / Q000737:chemistry / Q000302:isolation & purification; D001572:Benzofurans / Q000737:chemistry / Q000302:isolation & purification*; D003666:Decontamination / Q000379:methods; D006863:Hydrogen-Ion Concentration; D008670:Metals / Q000737:chemistry / Q000302:isolation & purification*; D010416:Pentachlorophenol / Q000737:chemistry* / Q000302:isolation & purification*; D000072317:Polychlorinated Dibenzodioxins / Q000031:analogs & derivatives* / Q000737:chemistry / Q000302:isolation & purification; D012989:Soil Pollutants / Q000737:chemistry / Q000302:isolation & purification*; D013501:Surface-Active Agents / Q000737:chemistry*; D014462:Ultrafiltration / Q000379:methods
chemical_list: D000468:Alkalies; D001572:Benzofurans; D008670:Metals; D000072317:Polychlorinated Dibenzodioxins; D012989:Soil Pollutants; D013501:Surface-Active Agents; C023614:dibenzofuran; D010416:Pentachlorophenol