Report

  • Category:
    Chemistry
  • Document type:
    Assignment
  • Level:
    Masters
  • Page:
    1
  • Words:
    708

Bodgit Brother

Company address: Sydney, New South Wales 2109, Australia

Report to:

Date: 02/06/2016

Report Number:

Number of Pages:

Report on:Determination of the Nitrite content in Waste water

Scope: Determination of Nitrite content in waste water by Chromatographic Technique

Background

Nitrites are forms of inorganic nitrogen that exist in the chemistry realm. Nitrite ion is abbreviated by the initials NO-2. Nitrite ions are normally reduced or oxidised when they react with other reactants to form compounds. The compound formed or rather the products are always dependent on the oxidising or reducing powers of the reactants. Nitrite ion is very important in the field of biochemistry due its property of being a potent vasodilator nitric oxide.

Report

Figure: A representation of the nitrite molecule

Nitrogen is the waste water takes the form of urea or the ammonia regardless of this nitrates and nitrites are still present. The main sources of nitrites in the waste water are the surface runoffs contain the elements of the agricultural fertilizers, leakages from the septic tanks and most important the erosion of the natural deposits containing the nitrites.

When nitrites levels are high in the waste water, then they pose a health risk to the human being. Such water has been established to cause diseases such as methaemoglobin in human beings and also cause excessive growth of algae in rivers and stream. Nitrite concentration is considered to excessive when its concentration levels exceed 1.mg/L. Therefore in this particular report we are undertaking an experiment into determining the nitrite contents in waste water by ion chromatography method. After the experiment, we will compare the obtained results with those of four other laboratories and compare their accuracies.

Materials

The major materials required are; Dionex DX-120 and DX-500 ion chromatography systems. We note that the DX-500 is a modular system that consists of a collection of equipments. They are;

  • GP50 Gradient pump,

  • A CD20 Conductivity detector

  • A finally the AD20 UV/Vis detector.

In the reagents category, we have the di-ionized water of substantial quantity and quality, sodium carbonate solution with a concentration of 0.18. A stock solution that is anionic and standardized is also required.

The first step was to inject water into a stream of carbonate –bicarbonate eluent. After this, the eluent is passed through a series of ion-exchangers. The ion exchangers comprise of guard columns and the separator columns

The anion of interest which in our case is the nitrite ion is separated on the basis of relative affinities for low capacity. The Separated anions are then directed through membrane suppressors where anions were converted to an acid which was established to conduct heavily. The carbonate-bicarbonate solution is converted in turn to a rather weak carbon acid. We note that the separated ion and acid were measured and identified based on their retention time and later compared with standard.

< The Determination of Inorganic Anions in Water by Ion Chromatography”; U.S. Environmental Protection Agency Method 300.0; Cincinnati, Ohio, 1993

Standard Test Method for Anions in Water by Chemically Suppressed Ion Chromatography”; Standard D4327-97; American Society for Testing and Materials: West Conshohocken, Pennsylvania, 1999; Vol. 11.01, p 420–427.>

The table numbered table 1 shows the results of the test undertaken by the Bodgit Brothers laboratory

Table 1: The results of Bodgit Brothers Laboratory

[NO-2]/μgL-1

Measured signal/arbitrary units

The following are the results of the samples which had been sourced from then clients and analyzed by the Bodgit Brothers laboratory amongst other four collaborative trials to determine the nitrite contents in waste water.

Table 2: A Comparison of Results from various Laboratories

Laboratories

Replicate/μgL-1 [NO-2]/

Smelly feet

How fragrant

Fresh odour

References

DEEB, B. S., & SLOAN, K. W. (1975). Nitrates, nitrites, and health. Urbana, Ill, Agricultural Experiment Station, Colleges of Agriculture and Veterinary Medicine, University of Illinois at Urbana-Champaign.

EYTINGON, A. I., & IZMEROV, N. F. (1982). Nitrites. Moscow, Centre for International Projects, GKNT.

HILL, M. J. (1996). Nitrates and nitrites in food and water. Cambridge, England, Woodhead Pub. http://site.ebrary.com/id/10833026.

The Determination of Inorganic Anions in Water by Ion Chromatography”; U.S. Environmental Protection Agency Method 300.0; Cincinnati, Ohio, 1993

“Standard Test Method for Anions in Water by Chemically Suppressed Ion Chromatography”; Standard D4327-97; American Society for Testing and Materials: West Conshohocken, Pennsylvania, 1999; Vol. 11.01, p 420–427.