Determination of total and organic nitrogen after persulphate oxidation

16 Determination of total and organic nitrogen after persulphate oxidation 

The determination of total and organic nitrogen has been one of the most difficult tasks in marine chemistry. The oldest procedure is the Kjeldahl digestion, which is still in use on a microscale. The Kjeldahl method and a method by Krogh and Keys (1934) decompose and reduce the nitrogen components to ammonia which is then determined. 

Most modem methods oxidize the nitrogen material with an oxidant aided by heating or UV light at a wavelength below 250nm (Armstrong et al, 1966). 

New methods use catalytic pyrolysis in an oxygen stream and detection of the nitrogen oxides by appropriate detectors or trapping in oxidizing aqueous solutions and subsequent determination as nitrate. The method and associated analytical problems have been discussed by, c.g., Williams etal. (1993). 

The oxidation of organic nitrogen compounds with potassium peroxodisulphate was introduced by Koroleff (1969,1973) and has subsequently become a recommended standard 

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See also in sourсe #XX -- [ ]

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