• UNDERSTAND
    Contamination Sources
  • UNDERSTAND
    Eutrophication

Abfall & Verschmutzung

Eine effiziente Abfallwirtschaft zur Erhaltung der Gesundheits- und Lebensqualität ist durch das stetige Wachstum der städtischen Bevölkerung und dem damit verbundenen gestiegenen Konsum zu einer wichtigen globalen Herausforderung geworden. Einerseits ist es wichtig, Abfall entsprechend seiner Bestandteile zu klassifizieren, andererseits muss aber auch die chemische Zusammensetzung von beispielsweise organischen Schadstoffen bestimmt werden, um eventuelle Flächensanierungen zu planen.

TOC im Abfall

Deponien sind u.a. danach klassifiziert, ob sie umweltgefährdenden Abfall aufnehmen dürfen oder nicht. In der Abfallwirtschaft gilt der TOC als ein Summenparameter für die Verunreinigung mit organischen Verbindungen oder zur Evaluierung, ob ein Material recycelt werden kann. Außerdem spielt die Bestimmung des TOC bei der Qualitätskontrolle von Industriematerialien wie Flugaschen, Zement oder Kaolin eine wichtige Rolle.

Temperaturabhängige Kohlenstoff-Fraktionen

Die einfache, klassische Unterscheidung in TOC und TIC steht mittlerweile eine Methode entgegen mit der zusätzlich elementarer Kohlenstoff (ROC) in Feststoffen bestimmt werden kann. Dies ist von Bedeutung für die Deponierung von Abfällen, da ROC biologisch inaktiv und ohne Umweltrelevanz ist, aber klassischerweise mit dem TOC mitbestimmt wird. Mit einem Temperaturrampenverfahren, das in der DIN19539 beschrieben und mit dem soli TOC® cube umgesetzt wird, können alle drei Kohlenstoff-Fraktionen bestimmt werden (TOC, ROC, TIC).

Schadstoffquellen

Mittels stabiler Isotope können komplexe Interaktionen von organischen Schadstoffen in der Umwelt nachvollzogen werden. Die Betrachtung der Quellen und des Verhaltens von Schadstoffen ist essentiell für die Planung von Sanierungen, Ressourcenmanagement und den Umweltschutz im Allgemeinen. Mit unseren Geräten können wir dazu beitragen diese Prozesse besser zu verstehen und unsere Naturwunder auch für die nächste Generation zu erhalten.

Publikationen zum Thema Abfall & Verschmutzung mit unseren Geräten

Unsere Kunden nutzen unsere Geräte für erstaunliche Forschungsprojekte im Bereich Abfall und Verschmutzung. Um Ihnen zu zeigen, wie unsere Kunden ihre Forschung durchführen und wie unsere IRMS-Geräte eingesetzt werden, haben wir eine Reihe von Fachpublikationen gesammelt, die unsere Produkte namentlich nennen. Die Informationen zu diesen Fachartikeln finden Sie unten. Durch Klicken auf den Link werden Sie zur Website des jeweiligen Zeitschriftenverlags weitergeleitet, wo Sie die Publikation herunterladen können.

Wenn Sie unsere Publikationsdatenbank durchsuchen möchten oder die Liste der Ergebnisse an sich selbst oder an Ihre Kollegen mailen möchten, dann werfen Sie einen Blick auf unsere gesamte Publikationsdatenbank.

84 Ergebnisse:

Determination of bromine stable isotopes using continuous-flow isotope ratio mass spectrometry.
Analytical chemistry (2005)
Orfan Shouakar-Stash, Shaun K Frape, Robert J Drimmie

A new methodology for bromine stable isotope determination by continuous-flow isotope ratio mass spectrometry (CF-IRMS) was developed. The technique was tested on inorganic samples. Inorganic bromide was precipitated in the form of silver bromide by using silver nitrate in a standard methodology. Bromine stable isotope analysis was carried out on methyl bromide (CH3Br) after converting silver bromide to methyl bromide by reacting it with methyl iodide (CH3I). The system used in this study is an IsoPrime IRMS, with analytical capabilities of both dual-inlet and continuous-flow modes coupled with an Agilent 6890 GC equipped with a CTC Analytics CombiPAL autosampler. This new technique measures samples as small as 0.2 mg of AgBr (1 micromol of Br-). The bromine stable isotope analysis using continuous flow technology showed excellent precision and accuracy. The internal precision using pure methyl bromide gas is better than +/-0.03 per thousand (+/-SD); the external precision using seawater standard is better than +/-0.06 per thousand (+/-SD) for n = 12. Moreover, the sample analysis time is 16 min, as compared to 75 min needed in previous techniques. This allows for 50 samples to be analyzed in 1 day, as compared to 8 samples using the conventional techniques. A series of natural saline formation waters and brines from sedimentary and crystalline rock environments was measured by this new methodology to test the potential natural range of delta81Br. The bromine isotopic composition of the samples ranged from 0.00 to +1.80 per thousand relative to standard mean ocean bromide (SMOB). Initial trends and distinctive isotopic difference were noticed between crystalline shield brines and sedimentary formation brines.

Determination of inorganic chlorine stable isotopes by continuous flow isotope ratio mass spectrometry.
Rapid communications in mass spectrometry : RCM (2005)
Orfan Shouakar-Stash, Robert J Drimmie, Shaun K Frape

Chlorine stable isotope analyses of inorganic samples were conducted using continuous flow isotope ratio mass spectrometry (CF-IRMS) coupled with gas chromatography (GC). Inorganic chloride was precipitated in the form of silver chloride (AgCl) by using silver nitrate in a standard methodology. Chlorine stable isotope analysis was carried out on methyl chloride (CH3Cl) after converting AgCl into CH3Cl by reacting it with methyl iodide (CH3I). The reaction between AgCl and CH3I took place in 20 mL size vials. Addition of CH3I was performed in a glove bag under helium flow. An Agilent 6890 gas chromatograph equipped with a CTC Analytics CombiPAL autosampler and a DB-5MS 60 m column was used to separate CH3Cl from CH3I. This new technique uses samples as small as 0.2 mg of AgCl (1.4 micromol of Cl-). The chlorine stable isotope analysis using continuous flow technology showed excellent precision and accuracy. The internal precision using pure CH3Cl gas is better than +/-0.04 per thousand (+/-STDV). The external precision using seawater standard is better than +/-0.07 per thousand (+/-STDV) for n=12. Moreover, the sample analysis time is much shorter and many more samples can be analyzed in one day than by using the conventional off-line techniques.

Identification of multiple sources of groundwater contamination by dual isotopes.
Ground water (2004)
Dugin Kaown, Orfan Shouakar-Stash, Jaeha Yang, Yunjung Hyun, Kang-Kun Lee

Chlorinated solvents are one of the most commonly detected groundwater contaminants in industrial areas. Identification of polluters and allocation of contaminant sources are important concerns in the evaluation of complex subsurface contamination with multiple sources. In recent years, compound-specific isotope analyses (CSIA) have been employed to discriminate among different contaminant sources and to better understand the fate of contaminants in field-site studies. In this study, the usefulness of dual isotopes (carbon and chlorine) was shown in assessments of groundwater contamination at an industrial complex in Wonju, Korea, where groundwater contamination with chlorinated solvents such as trichloroethene (TCE) and carbon tetrachloride (CT) was observed. In November 2009, the detected TCE concentrations at the study site ranged between nondetected and 10,066 µg/L, and the CT concentrations ranged between nondetected and 985 µg/L. In the upgradient area, TCE and CT metabolites were detected, whereas only TCE metabolites were detected in the downgradient area. The study revealed the presence of separate small but concentrated TCE pockets in the downgradient area, suggesting the possibility of multiple contaminant sources that created multiple comingling plumes. Furthermore, the variation of the isotopic (δ(13) C and δ(37) Cl) TCE values between the upgradient and downgradient areas lends support to the idea of multiple contamination sources even in the presence of detectable biodegradation. This case study found it useful to apply a spatial distribution of contaminants coupled with their dual isotopic values for evaluation of the contaminated sites and identification of the presence of multiple sources in the study area.

On-line technique for the determination of the delta37Cl of inorganic and total organic Cl in environmental samples.
Analytical chemistry (2004)
Leonard I Wassenaar, Geoff Koehler

Here we describe an on-line method for measuring delta(37)Cl values of chloride bearing salts, waters, and organic materials using multicollector continuous-flow isotope ratio mass spectrometry (CF-IRMS). Pure AgCl quantitatively derived from total Cl in water, inorganic Cl salts, and biological samples was reacted with iodomethane in evacuated 10-mL stopper sealed glass vials to produce methyl chloride gas. A GV Instruments Multicollector CF-IRMS with CH(3)Cl optimized collector geometry was modified to accommodate a headspace single-sample gas injection port prior to a GC column. The GC column was a 2-m Porapak-Q packed column held at 160 degrees C. The resolved sample CH(3)Cl was introduced to the IRMS source in a helium stream via an open split. delta(37)Cl values were calculated by measurement of CH(3)Cl at m/z 52/50 and by comparison to a reference pulse of CH(3)Cl calibrated to standard mean ocean chloride. Sample CH(3)Cl analysis time was approximately 6 min. Injections of 40 microL of pure CH(3)Cl gas yielded a repeatability (+/-SD) of +/-0.06 per thousand for delta(37)Cl (n = 10). Combined GC and IRMS source linearity for CH(3)Cl was <0.2 per thousand/nA (V) peak height. External repeatability, based on processing of seawater and NaCl reference solutions, was better than +/-0.08 per thousand. The smallest sample for delta(37)Cl analysis by this method was approximately 0.2 micromol of Cl. Selected results from a river basin and biological samples study illustrate the potential of on-line chlorine isotope assays in environmental pollution studies.