Format

Send to

Choose Destination
See comment in PubMed Commons below
Environ Pollut. 2010 Aug;158(8):2672-8. doi: 10.1016/j.envpol.2010.04.022. Epub 2010 Jun 3.

Modeling polychlorinated biphenyl sorption isotherms for soot and coal.

Author information

  • 1Institute for Risk Assessment Sciences (IRAS), Utrecht University, 3508 TD Utrecht, The Netherlands.

Abstract

Sorption isotherms (pg-ng/L) were measured for 11 polychlorinated biphenyls (PCBs) of varying molecular planarity from aqueous solution to two carbonaceous geosorbents, anthracite coal and traffic soot. All isotherms were reasonably log-log-linear, but smooth for traffic soot and staircase-shaped for coal, to which sorption was stronger and more nonlinear. The isotherms were modeled using seven sorption models, including Freundlich, (dual) Langmuir, and Polanyi-Dubinin-Manes (PDM). PDM provided the best combination of reliability and mechanistically-interpretable parameters. The PDM normalizing factor Z appeared to correlate negatively with sorbate molecular volume, dependent on the degree of molecular planarity. The modeling results supported the hypothesis that maximum adsorption capacities (Q(max)) correlate positively with the sorbent's specific surface area. Q(max) did not decrease with increasing sorbate molecular size, and adsorption affinities clearly differed between the sorbents. Sorption was consistently stronger but not less linear for planar than for nonplanar PCBs, suggesting surface rather than pore sorption.

PMID:
20605296
DOI:
10.1016/j.envpol.2010.04.022
[PubMed - indexed for MEDLINE]
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Elsevier Science
    Loading ...
    Support Center