title: Adsorptive fractionation of dissolved organic matter (DOM) by carbon nanotubes.
abstract: Dissolved organic matter (DOM) and carbon nanotubes are introduced into aquatic environments. Thus, it is important to elucidate whether their interaction affects DOM amount and composition. In this study, the composition of DOM, before and after interactions with single-walled carbon nanotubes (SWCNTs), was measured and the adsorption affinity of the individual structural fractions of DOM to SWCNTs was investigated. Adsorption of DOM to SWCNTs was dominated by the hydrophobic acid fraction, resulting in relative enhancement of the hydrophilic character of non-adsorbed DOM. The preferential adsorption of the HoA fraction was concentration-dependent, increasing with increasing concentration. Adsorption affinities of bulk DOM calculated as the normalized sum of affinities of the individual structural fractions were similar to the measured affinities, suggesting that the structural fractions of DOM act as independent adsorbates. The altered DOM composition may affect the nature and reactivity of DOM in aquatic environments polluted with carbon nanotubes.
authors.affiliation: Department of Soil and Water Sciences, Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, P.O. Box 12, Rehovot 7610001, Israel.
authors.forename: Maya
authors.initials: M
authors.lastname: Engel
authors.affiliation: Department of Soil and Water Sciences, Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, P.O. Box 12, Rehovot 7610001, Israel. Electronic address: benny.chefetz@mail.huji.ac.il.
authors.forename: Benny
authors.initials: B
authors.lastname: Chefetz
mesh_terms: D000327:Adsorption; D057927:Hydrophobic and Hydrophilic Interactions; D008956:Models, Chemical; D037742:Nanotubes, Carbon / Q000737:chemistry*; D012987:Soil / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000737:chemistry*
chemical_list: D037742:Nanotubes, Carbon; D012987:Soil; D014874:Water Pollutants, Chemical
keywords: Carbon nanomaterial; Characterization; Composition; Fraction; Sorption