Fluxes of PAHs from coal tar-impacted river sediment under variable seepage rates

Seunghun Hyun, Hyun Park, Mi Youn Ahn, Andrew R. Zimmerman, Chad T. Jafvert

Research output: Contribution to journalArticle

3 Citations (Scopus)

Abstract

The flux of several polycyclic aromatic hydrocarbons (PAHs) from coal tar-impacted river sediment was measured under various seepage rates in a laboratory scale. The batch PAH equilibrium data between aqueous phase (Ceq) and sediment phase was well-explained using a Raoult's law approach. In the flux measurement from column study, the steady-state PAH concentrations (C) in the effluent solution were affected by a time-dependent nonequilibrium process; the seepage velocity was inversely proportional to the C of PAH in the effluents. With a high seepage velocity of 4.06cmd-1, a large initial concentration was observed, possibly due to the greater disparity between C and Ceq. This initial-flush export leveled off after a few pore volumes had been displaced. The chemical flux pattern of PAH was conceptually depicted by superimposing two analytical solutions, such as a slug lease followed by rate-limited solute lease. Under quiescent conditions, the sediment pore-water reached dissolution equilibrium with the solid phase. However, under dynamic groundwater seepage conditions, the seepage water flowing through sediment pores did not reach dissolution equilibrium, which was evidence of nonequilibrium dissolution. In conclusion, the mass flux of PAHs from coal tar-impacted sediment is determined by concurrent effect of the groundwater seepage rate and rate-limited PAH concentration in seepage water.

Original languageEnglish
Pages (from-to)1261-1267
Number of pages7
JournalChemosphere
Volume80
Issue number11
DOIs
Publication statusPublished - 2010 Sep

Keywords

  • Coal tar
  • Nonequilibrium
  • Polycyclic aromatic hydrocarbons
  • Sediment
  • Seepage

ASJC Scopus subject areas

  • Environmental Engineering
  • Environmental Chemistry
  • Chemistry(all)
  • Pollution
  • Health, Toxicology and Mutagenesis

Fingerprint Dive into the research topics of 'Fluxes of PAHs from coal tar-impacted river sediment under variable seepage rates'. Together they form a unique fingerprint.

  • Cite this