Sorption behavior of dibutyl phthalate and dioctyl phthalate by aged refuse

Environ Sci Pollut Res Int. 2014 Jun;21(12):7641-9. doi: 10.1007/s11356-014-2672-7. Epub 2014 Mar 12.

Abstract

Sorption is a fundamental process controlling the transformation, fate, degradation, and biological activity of hydrophobic organic contaminants in the environment. We investigated the kinetics, isotherms, and potential mechanisms for the sorption of two phthalic acid esters (PAEs), dibutyl phthalate (DBP) and dioctyl phthalate (DOP), on aged refuse. A two-compartment first-order model performed better than a one-compartment first-order model in describing the kinetic sorption of PAEs, with a fast sorption process dominating. Both the Freundlich and Dubinin-Astakhov (DA) models fit the sorption isotherms of DBP and DOP, with the DA model being of a better fit over the range of apparent equilibrium concentrations. The values of the fitting parameters (n, b, E) of the PAEs suggest nonlinear sorption characteristics. Higher predicted partition coefficient values and saturated sorption capacity existed in refuse containing larger quantities of organic matter. The sorption capacity of DOP was significantly higher than that of DBP. PAE sorption was dependent on liquid phase pH. Desorption hysteresis occurred in PAE desorption experiments, especially for the long-chain DOP. PAEs may therefore be a potential environmental risk in landfill.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adsorption
  • Biodegradation, Environmental
  • Carbon / analysis
  • China
  • Dibutyl Phthalate / chemistry*
  • Diethylhexyl Phthalate / chemistry*
  • Esters / chemistry
  • Humic Substances / analysis
  • Hydrogen-Ion Concentration
  • Kinetics
  • Models, Theoretical
  • Nitrogen / analysis
  • Phosphorus / analysis
  • Refuse Disposal / methods

Substances

  • Esters
  • Humic Substances
  • Dibutyl Phthalate
  • Phosphorus
  • Carbon
  • Diethylhexyl Phthalate
  • Nitrogen