Total Kjeldahl Nitrogen Colorimetric Testing for Discrete and Segmented Flow Analyzers

Changing the Paradigm for Water Pollution Monitoring
Oral Presentation

Prepared by S. Leibenguth
SEAL Analytical, 6501 West Donges Bay Road, Mequon, Wisconsin, 53092, United States


Contact Information: sleibenguth@seal-us.com; 262-241-7900


ABSTRACT

Total Kjeldahl Nitrogen is currently tested in many working laboratories, however, the procedure can vary from one lab to another. There are several options available for this colorimetric test. We will discuss differences in the digestion procedure, including choosing mercury or a copper catalyst, type of boiling granules, and consistency in reconstitution. We will also discuss troubleshooting issues associated with the colorimetric reaction after digestion. The topics to be discussed will be pH of the reaction, matrix matching, reaction interferences, and chemical contamination.