title: Kinetics of hydrophobic organic contaminant extraction from sediment by granular activated carbon.
abstract: Ex situ solid phase extraction with granular activated carbon (GAC) is a promising technique to remediate contaminated sediments. The methods' efficiency depends on the rate by which contaminants are transferred from the sediment to the surface of GAC. Here, we derive kinetic parameters for extraction of polycyclic aromatic hydrocarbons (PAH) from sediment by GAC, using a first-order multi-compartment kinetic model. The parameters were obtained by modeling sediment-GAC exchange kinetic data following a tiered model calibration approach. First, parameters for PAH desorption from sediment were calibrated using data from systems with 50% (by weight) GAC acting as an infinite sink. Second, the estimated parameters were used as fixed input to obtain GAC uptake kinetic parameters in sediment slurries with 4% GAC, representing the ex situ remediation scenario. PAH uptake rate constants (kGAC) by GAC ranged from 0.44 to 0.0005 d(-1), whereas GAC sorption coefficients (KGAC) ranged from 10(5.57) to 10(8.57) L kg(-1). These values are the first provided for GAC in the presence of sediment and show that ex situ extraction with GAC is sufficiently fast and effective to reduce the risks of the most available PAHs among those studied, such as fluorene, phenanthrene and anthracene.
authors.affiliation: Subdepartment of Environmental Technology, Department of Agrotechnology and Food Science, Wageningen University, P.O. Box 17, 6700 AA Wageningen, The Netherlands. Electronic address: Magdalena.Rakowska@wur.nl.
authors.forename: M I
authors.initials: MI
authors.lastname: Rakowska
authors.affiliation: Aquatic Ecology and Water Quality Management Group, Department of Environmental Sciences, Wageningen University, P.O. Box 47, 6700 AA Wageningen, The Netherlands.
authors.forename: D
authors.initials: D
authors.lastname: Kupryianchyk
authors.affiliation: Subdepartment of Environmental Technology, Department of Agrotechnology and Food Science, Wageningen University, P.O. Box 17, 6700 AA Wageningen, The Netherlands.
authors.forename: M P J
authors.initials: MP
authors.lastname: Smit
authors.affiliation: Aquatic Ecology and Water Quality Management Group, Department of Environmental Sciences, Wageningen University, P.O. Box 47, 6700 AA Wageningen, The Netherlands; IMARES - Institute for Marine Resources & Ecosystem Studies, Wageningen UR, P.O. Box 68, 1970 AB IJmuiden, The Netherlands.
authors.forename: A A
authors.initials: AA
authors.lastname: Koelmans
authors.affiliation: Subdepartment of Environmental Technology, Department of Agrotechnology and Food Science, Wageningen University, P.O. Box 17, 6700 AA Wageningen, The Netherlands.
authors.forename: J T C
authors.initials: JT
authors.lastname: Grotenhuis
authors.affiliation: Subdepartment of Environmental Technology, Department of Agrotechnology and Food Science, Wageningen University, P.O. Box 17, 6700 AA Wageningen, The Netherlands.
authors.forename: H H M
authors.initials: HH
authors.lastname: Rijnaarts
mesh_terms: D000327:Adsorption; D002606:Charcoal; D002851:Chromatography, High Pressure Liquid; D052918:Environmental Restoration and Remediation / Q000379:methods*; D019015:Geologic Sediments / Q000032:analysis*; D007700:Kinetics; D008956:Models, Chemical; D011084:Polycyclic Aromatic Hydrocarbons / Q000302:isolation & purification*; D012989:Soil Pollutants / Q000302:isolation & purification*; D052616:Solid Phase Extraction / Q000379:methods
chemical_list: D011084:Polycyclic Aromatic Hydrocarbons; D012989:Soil Pollutants; D002606:Charcoal
keywords: Granular activated carbon; Kinetics; PAHs; Sediment remediation