4 Material und Umwelt
Filtern
Dokumenttyp
- Zeitschriftenartikel (12) (entfernen)
Sprache
- Englisch (12)
Referierte Publikation
- ja (12)
Schlagworte
- Sewage sludge (2)
- Analytical methods (1)
- Aspergillus (1)
- BTEX (1)
- Bacteria (1)
- Biocides (1)
- Biofouling (1)
- Biosynthesis (1)
- CEC-L-103 (1)
- Combustion Ion Chromatography (1)
- Conjugate (1)
- Construction products (1)
- Degradation (1)
- Environmental Chemistry (1)
- Environmental Engineering (1)
- Fertilizer (1)
- Fluorescence (1)
- Fluoride (1)
- Food (1)
- Food fermentation (1)
- Fungi (1)
- Fusarium (1)
- GC-FID (1)
- Gas analysis (1)
- General Chemistry (1)
- General Medicine (1)
- Health, Toxicology and Mutagenesis (1)
- ISO REMCO (1)
- Interlaboratory comparison (1)
- LC-MS/MS (1)
- Mass spectrometry (1)
- Modified mycotoxins (1)
- Mycotoxin (1)
- Nanomaterials (1)
- Organic contaminants (1)
- PFAS (1)
- Per- and Polyfluoroalkyl substances (PFAS) (1)
- Phosphorus elimination (1)
- Phosphorus recovery (1)
- Pollution (1)
- Polypropylene (1)
- Polystyrene (1)
- Polyurethanes (1)
- Public Health, Environmental and Occupational Health (1)
- Reference material (1)
- Reference organisms (1)
- Rhizopus (1)
- Rhizopus and Aspergillus oryzae (1)
- Soil (1)
- Sorption (1)
- Standardization (1)
- Substance release (1)
- Thermal degradation (1)
- Thermo-desorption (1)
- Transformation (1)
- UV radiation (1)
- Validation trial (1)
- Wastewater (1)
- Water contact (1)
- XANES (1)
- XRF (1)
- Zearalenone (1)
- Zearalenone sulfate (1)
- a-zearalenol (1)
Organisationseinheit der BAM
- 1.7 Organische Spuren- und Lebensmittelanalytik (12) (entfernen)
Paper des Monats
- ja (1)
Thermo-Desorption Gas Chromatography-Mass Spectrometry (TD-GC-MS) was used to investigate the thermal degradation of two different polyurethanes (PU). PU samples were heated at different heating rates and the desorbed products were collected in a cold injection system and thereafter submitted to GC-MS. Prospects and limitations of the detection and quantification of semi-volatile degradation products were investigated. A temperature dependent PU depolymerization was
found at temperatures above 200 °C proved by an increasing release of 1,4-butanediol and methylene diphenyl diisocyanate (MDI) representing the main building blocks of both polymers. Their release was monitored quantitatively based on external calibration with authentic compounds. Size Exclusion Chromatography (SEC) of the residues obtained after thermodesorption confirmed the initial competitive degradation mechanism indicating an equilibrium of crosslinking and depolymerization as previously suggested. Matrix-Assisted Laser Desorption Ionization (MALDI) mass spectrometry of SEC fractions of thermally degraded PUs provided additional hints on degradation mechanism.
Here, we report a comparative study of different sum parameter analysis methods for the extraction of per- and polyfluoroalkyl substances (PFAS) from manufactured consumer products, which can be measured by combustion ion chromatography (CIC). Therefore, a hydrolysis-based extraction method was further developed, which accounts for the addition of hydrolyzable covalently bound polyfluoroalkylated side-chain polymers (SFPs) to the extractable organic fluorine portion of the mass balance proposed as "hydrolyzable organically bound fluorine" (HOF). To test this hypothesis, the method was applied to 39 different consumer products containing fluoropolymers or monomeric PFAS taken from four different categories: outdoor textiles, paper packaging, carpeting, and permanent baking sheets. We also evaluated the method's efficiency by extracting four synthesized fluorotelomer polyacrylate reference compounds. The total fluorine (TF) and extractable organically bound fluorine (EOF) values were measured through CIC using established protocols. The TF values ranged from sub-ppb to %-levels, depending on the compound class. All samples showed results for hydrolyzed organofluorine (HOF) between 0.03 and 76.3 μg/g, while most EOF values were lower (<LOD to 58.1 μg/g). Moreover, the methods were contrasted with the "total hydrolyzable precursor" (THP) assay analyzed using gas-chromatography coupled mass spectrometry (GC-MS), which yielded concentrations of 6:2–10:2 fluorotelomer alcohols (<LOD-568 μg/g) for textile and paper samples. Furthermore, targeted analytical investigation of 25 compounds via liquid chromatography coupled tandem mass spectrometry (LC-MS/MS) was conducted and accounted for significantly lower sum amounts (<LOD-0.98 μg PFAS/g). To estimate the fluorine mass balance of all methods, the fluorine levels of target analytical data were calculated and compared to the sum parameter values and evaluated. Finally, the efficiency of the extraction method was approximated by the recovery analysis of four selected SFP model compounds compared to their TF values, yielding 36.7–74.0% after extraction and 3.8–36.3% after processing the extract for the HOF sum parameter.