Toggle Main Menu Toggle Search

Open Access padlockePrints

Modeling polychlorinated biphenyl mass transfer after amendment of contaminated sediment with activated carbon

Lookup NU author(s): Professor David Werner, Professor Richard Luthy

Downloads

Full text for this publication is not currently held within this repository. Alternative links are provided below where available.


Abstract

The sorption kinetics and concentration of polychlorinated biphenyls (PCBs) in historically polluted sediment is modeled to assess a remediation strategy based on in situ PCB sequestration by mixing with activated carbon (AC). We extend our evaluation of a model based on intraparticle diffusion by including a biomimetic semipermeable membrane device (SPMD) and a first-order degradation rate for the aqueous phase. The model predictions are compared with the previously reported experimental PCB concentrations in the bulk water phase and in SPMDs. The simulated scenarios comprise a marine and a freshwater sediment, four PCB congeners, two AC grain sizes, four doses of AC, and comparison with laboratory experiments for up to 540 days of AC amendment slowly mixed with sediment. The model qualitatively reproduces the observed shifts in the PCB distribution during repartitioning after AC amendment but systematically overestimates the overall effect of the treatment in reducing aqueous and SPMD concentrations of PCBs by a factor of 2-6. For our AC application in sediment, competitive sorption of the various solutes apparently requires a reduction by a factor of 16 of the literature values for the AC-water partitioning coefficient measured in pure aqueous systems. With this correction, model results and measurements agree within a factor of 3. We also discuss the impact of the nonlinearity of the AC sorption isotherm and first-order degradation in the aqueous phase. Regular mixing of the sediment accelerates the benefit of the proposed amendment substantially. But according to our scenario, after AC amendment is homogeneously mixed into the sediment and then left undisturbed, aqueous PCB concentrations tend toward the same reduction after approximately 5 or more years. © 2006 American Chemical Society.


Publication metadata

Author(s): Werner D, Ghosh U, Luthy RG

Publication type: Article

Publication status: Published

Journal: Environmental Science and Technology

Year: 2006

Volume: 40

Issue: 13

Pages: 4211-4218

ISSN (print): 0013-936X

ISSN (electronic): 1520-5851

Publisher: American Chemical Society

URL: http://dx.doi.org/10.1021/es052215k

DOI: 10.1021/es052215k


Altmetrics

Altmetrics provided by Altmetric


Actions

Find at Newcastle University icon    Link to this publication


Share