Determination of NH4+ in Environmental Water with Interfering Substances Using the Modified Nessler Method

Abstract EN

Nitrogen is an essential element in the environment.

If excess nitrogen including NH4 + is present in water, however, it can result in algae blooming and eventually the destruction of the aquatic ecosystem.

Therefore, the determination of NH4 + in streams, lakes, and effluents of the treatment facilities has long been carried out.

The Nessler method is the most common spectrophotometric method to measure NH4 + in water.

However, the result of the method becomes inaccurate if there are interfering substances such as Cl2, Cl−, hardness-causing compounds (e.g., Mg2+), and Fe2+ in target water samples.

In this study, therefore, the traditional Nessler method has been modified to eliminate the effects of interfering substances; the so-called MS was added to water samples.

In addition, the polyvinyl alcohol reagent as a dispersing agent was added to water samples to increase the sensitivity and reproducibility of the method.

The modified method could successfully analyze NH4 + of water samples even with the interfering substance at high concentration.