Particulates, determination organic content

Methods for Particulates and Gases. For determining the organic content of particulates we have found the usual method of collecting airborne particulates on specially cleaned fiberglass filters to be suitable. The particulate filters then are extracted and the organic extract can be further partitioned by the above scheme or analyzed without any separation. SHALE OIL... 

Orren [663] used atomic absorption spectrometry to determine these elements in seawater in both their soluble and insoluble forms. The alkali metals are determined directly, but the other elements are first concentrated by solvent extraction. The particulate matter content is derived by dissolving the membranes used to filter the sample and determine the metals in the resulting solution. For organic standards of known metal content, the efficiency of the technique was almost 100%. 

Dankers and Laane [43] compared two methods, based on wet oxidation with potassium peroxydisulphate and loss on ignition at 560°C, for the determination of particulate organic carbon in estuarine suspended matter. They found that in estuarine sediments with a high clay content, loss on... 

Analysis of PNAs is a complex and challenging task for the analytical chemist, because even in relatively simple samples such as air particulates the PNAs must be isolated from a mixture of materials. A much more difficult problem is the determination of PNAs in crude oil or petroleum products. In this case the parent PNAs are present as minor constituents in a matrix of materials very similar to the PNAs themselves. Another extremely difficult sample type to analyze for PNA content is foodstuffs. Difficulty arises here because of the very low PNA content (ppb) and the complex organic nature of the materials. 

The sampling of water and soil for speciation analysis is not significantly different than for total metal content determinations. The distribution of metals ranges from truly dissolved to particulate-bound species. This includes inorganic complexes or complexes with organic molecules, surface-bound metals (organic and inorganic... 

This method was developed by Stefan Huber (Karlsruhe, Germany) and consists of three size exclusion chromatography columns which divide the organic carbon into several fractions as a function of size, but also hydrophobic and ionogenic characteristics. A sample of up to 3 mL is injected into the instrument and filtered in-line with a 0.45 )um filter. The deposit on the filter is backwashed after 5 minutes and directly analysed with the TOC analyser to determine the particulate organic carbon content (POC). 

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