What are the expected results of the Nitrogen Primary Standard, set of 3 for TKN method 8075?

Document ID

Document ID TE393

Version

Version 5.0

Status

Status Published

Published Date

Published Date 06/13/2019
Question
What are the expected results of the Nitrogen Primary Standard, set of 3 for TKN method 8075?
Summary
Expected Total Kjeldahl Nitrogen (TKN) primary standard results
Answer
The expected results of the Nitrogen Primary Standard, set of 3 (Product # 2277800) for TKN method 8075 depends on whether you add the standard (solid) directly to the digestion flask or whether you prepare a solution from the standard and digest a portion of the solution.

From a solid digestion (solid standard added directly to digestion flask), the result after the calculation in the last step of the procedure should be:
Ammonium PTSA 74,020 ppm
Glycine PTSA 56,640 ppm
Nicotinic Acid PTSA 47,430 ppm.

From a liquid digestion (solution prepared from 10 g standard diluted to 1 liter), the result after the calculation in the last step of the procedure should be:
Ammonium PTSA standard 740 ppm
Glycine PTSA standard 566 ppm
Nicotinic Acid PTSA standard: 474 ppm.
The results of the liquid digestion may differ if an amount other than 10 g were used to make the solution. If the actual result is significantly different (greater than 10 %) from the theoretical result, follow the standard solution method in the TKN test procedure using a 1 mg/L ammonia standard solution. If the results using an ammonia standard are correct, there may be a problem with the digestion procedure.

This information is from the Digesdahl user manual. Is there a user manual for the Digesdahl?

Was this answer helpful?

Submitting...
Thank you for your feedback!
There was an error with your submission. Please try again.