title: Incorporation mechanisms of a branched nonylphenol isomer in soil-derived organo-clay complexes during a 180-day experiment.
abstract: The incorporation process of a defined (13)C- and (14)C-labeled nonylphenol isomer (4-(3,5-dimethylhept-3-yl)phenol) into soil-derived organo-clay complexes was investigated. Isolated organo-clay complexes were separated into humic subfractions. Noninvasive ((13)C-CP/MAS NMR) and invasive methods (sequential chemical degradation, pyrolysis) were applied to obtain detailed information about the mode of incorporation, chemical structure, and change of the incorporation character of nonextractable residues in course of incubation. (13)C-CP/MAS NMR measurements of humic acids revealed an increasing incorporation of phenolic compounds during the experimental time which was referred to residues of the introduced (13)C-labeled NP isomer. Detailed investigations by means of sequential chemical degradation indicated a predominant incorporation of nonextractable NP isomer residues via reversible ester (amide) bonds. In course of time, the amount of releasable compounds decreased, pointing to altering processes which affected the mode of incorporation. BBr3-treatment, RuO4 oxidation, and thermochemolysis released only low portions of nonextractable radioactivity giving evidence of strongly incorporated residues. With the comprehensive application of complementary methods (e.g., humic matter fractionation, (13)C-CP/MAS NMR, sequential chemical degradation) it was possible to provide a comparatively detailed insight into the incorporation behavior of the applied NP isomer.
authors.affiliation: Institute of Geology and Geochemistry of Petroleum and Coal, RWTH Aachen University, Aachen, Germany.
authors.forename: Patrick
authors.initials: P
authors.lastname: Riefer
authors.forename: Timm
authors.initials: T
authors.lastname: Klausmeyer
authors.forename: Alina
authors.initials: A
authors.lastname: Adams
authors.forename: Burkhard
authors.initials: B
authors.lastname: Schmidt
authors.forename: Andreas
authors.initials: A
authors.lastname: Schäffer
authors.forename: Jan
authors.initials: J
authors.lastname: Schwarzbauer
mesh_terms: D001896:Boron Compounds / Q000737:chemistry; D006812:Humic Substances; D007536:Isomerism; D010636:Phenols / Q000737:chemistry*; D000644:Quaternary Ammonium Compounds / Q000737:chemistry; D017975:Ruthenium Compounds / Q000737:chemistry; D017640:Silicates / Q000737:chemistry*; D012987:Soil / Q000737:chemistry; D012989:Soil Pollutants / Q000737:chemistry*
chemical_list: D001896:Boron Compounds; D006812:Humic Substances; D010636:Phenols; D000644:Quaternary Ammonium Compounds; D017975:Ruthenium Compounds; D017640:Silicates; D012987:Soil; D012989:Soil Pollutants; C025256:nonylphenol; C027646:ruthenium tetraoxide; C027917:tetramethylammonium