Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
9675876 | Colloids and Surfaces A: Physicochemical and Engineering Aspects | 2005 | 10 Pages |
Abstract
Amphiphilic natural organic matter (NOM) in soil, water and sediments plays an important role in the fate of low-soluble hydrophobic organic compounds (HOC) in the environment. Scaling NOM structural factors, which affect the transport and immobilization of HOC, is rather involved due to the complexity of the NOM materials. Sorption properties of hydrophobically modified polyacrylic (HMPA) polymers as NOM model substances for pyrene were investigated and discussed with regard to reported NOM results. Emission fluorescence spectroscopic properties of pyrene and potentiometric titrations were used to characterize the hydrophobic and acidic properties of HMPA samples. Excitation fluorescence spectroscopy allowed a speciation of pyrene molecules. Overall complexation constants β1 and β2 of pyrene with hydrophobic moieties (-C8H17) and (-C16H33) were calculated depending on the pH and electrolyte cation nature at an ionic strength of 10 mM, typical of soil solution conditions. Aggregation of HMPA molecules was detected by photon correlation spectroscopy. Normalized sorption constant Koc values for pyrene with HMPA samples similar to reported values with NOM support recent observations on the contribution of aliphatic moieties to the binding of polyaromatic hydrocarbons (PAH). The HMPA samples also model the partitioning behavior of hydrophobic micelle-like structures of NOM.
Related Topics
Physical Sciences and Engineering
Chemical Engineering
Colloid and Surface Chemistry
Authors
Frauke BaÃmann-Schnitzler, Jean-Marie Séquaris,