TAN {AquaAnalytix} | R Documentation |
Total Ammonia Nitrogen (TAN) using Indophenol Method
Description
Total ammonia nitrogen (TAN) is a measure of the total amount of ammonia nitrogen present in a sample, including both ammonium ion and ammonia gas. Ammonia exists in two forms in water: ionized and unionized. The primary difference between ionized and unionized ammonia is their chemical state, which can affect their behavior and toxicity. Only a fraction of the TAN exists as toxic (un-ionized) ammonia, and a balance exists between it and the nontoxic ionized ammonia based on pH and temperature.Unionized ammonia is more toxic to aquatic life than ionized ammonia.
Principle of analysis:
Water sample is treated in an alkaline citrate medium with sodium hypochlorite and phenol in the presence of sodium nitroprusside which acts as a catalyzer and colour intensifier. The blue indophenol colour formed with ammonia is measured spectrophotometrically at 640nm. APHA(2017,ISBN:9780875532875).
Usage
TAN(Conc_std_sol, A_s, A_b, A_st)
Arguments
Conc_std_sol |
Concentration of standard solution |
A_s |
Mean absorbance of samples |
A_b |
Mean absorbance of blanks |
A_st |
Mean absorbance of standards |
Value
Total Ammonia Nitrogen (TAN) (in micro gm/L)
References
APHA, 2017. Standard methods for examination of water and wastewater, 23rd edn. APHA, AWWA, WPCF, Washington
Examples
TAN(1000, 0.17, 0.1, 0.8)