Interaction of phenanthrene with dissolved organic matter and its fractions from leachate of different landfill ages

摘要

Dissolved organic matter (DOM) in leachate from landfills of three different ages (0, 5, and 10 year) was partitioned into hydrophobic acid, hydrophobic neutral, and hydrophilic matter fractions using the fractionation method employing XAD-8 resin. The spectroscopic characteristics of these fractions were determined through constant-wavelength synchronous fluorescence spectrome-try (CWSFS). The interaction characteristic of phenanthrene with these fractions was determined through the fluorescence quenching method and CWSFS. The results revealed that the composition of DOM became complex with the increase in landfill age. The partition coefficients (K_(doc)) for the three DOM samples of different landfill ages are in the order 10 a DOM > 5 a DOM > 0 a DOM. The hydrophobic fraction showed the highest K_(doc) value among the DOM fractions. Lower linearity Stern-Volmer plots were observed in 10 a DOM and its hydrophobic fractions. CWSFS spectra showed that a special site was fully occupied with the addition of the quencher. Desorption was found in some fractions. Therefore, CWSFS is a sensitive tool for the detection of DOM-polycyclic aromatic hydrocarbon interaction.