• DOI:10.1021/ES990537G
• Corpus ID: 96773397

Influence of Bisolute Competition on the Desorption Kinetics of Polycyclic Aromatic Hydrocarbons in Soil

@article{White1999InfluenceOB,
  title={Influence of Bisolute Competition on the Desorption Kinetics of Polycyclic Aromatic Hydrocarbons in Soil},
  author={Jason Christopher White and Joseph J. Pignatello},
  journal={Environmental Science \& Technology},
  year={1999},
  volume={33},
  pages={4292-4298}
}

• J. White, J. Pignatello
• Published 26 October 1999
• Chemistry
• Environmental Science & Technology

The dual-mode (partition/hole-filling) model of soil organic matter (SOM) as a heterogeneous polymerlike sorbent of hydrophobic compounds predicts that a competing solute will accelerate diffusion of the primary solute by blocking the holes, allowing the principal solute to move faster through the SOM matrix. We tested this hypothesis with phenanthrene as the primary solute and pyrene as the competing solute in two sterile soils of widely different organic carbon content (1.4 and 43.9%). Two- and 33-d isotherms of phenanthrene in both soils were nonlinear, indicating a heterogeneous distribution of sites. Pyrene suppressed phenanthrene sorption and increased the linearity of its isotherm. Uptake (adsorption) rates were measured in batch systems after preincubating with pyrene. Desorption was measured by the sequential dilution technique at constant pyrene concentration in the supernatant. The design of the experiment precluded comparison of adsorption rates, but desorption rates increased significantly (b...