Ammonia Nitrogen Determination

Ammonia Nitrogen Determine as directed under Ammonia Nitrogen, Appendix I IIC. ... 

Ammonia and ammonium ions in industrial water streams, including waste-water streams, can be determined by either of two methods (ASTM Procedure D1426). In the first, the sample is buffered to a pH of 7.4 and distilled into a solution of boric acid where the ammonia nitrogen is deterrnined colorimetricaHy with Nessler reagents or titrated using standard sulfuric acid. 

A olear, colorless liquid, containing 150 gm. of pure, crystallized citric acid and 23 gin. of ammonia-nitrogen (=27.93 gm. of NII I) per liter. The solution has an acid reaction to litmus paper and Ls used for determining citrate-soluble phosphoric, acid in Thomas slag, by the method of Wagner. 

KJELDAHL TEST. An analytical method for determination of nitrogen in certain organic compounds. It involves addition of a small amount of anhydrous potassium sulfate to the test compound, followed by healing the mixture with concentrated sulfuric acid, often with a catalyst such ns copper sulfate. As a result ammonia is formed. Alter alkaly/ing the mixture with sodium hydroxide, the ammonia is separated by distillation, collected in standard acid, and the nitrogen determined by back-iilruiion. 

Nitrogen determination by perchloric acid digestion of coal without catalysts is reportedly safe and much more rapid than the conventional Kjeldahl procedure. Nitrogen is determined in the digest by the usual ammonia evolution and titration. However, extreme care should be taken whenever perchloric acid is used. Nuclear reactions have been applied successfully to the determination of nitrogen in coal. 

Tecator Ltd. [16] have described a flow injection analysis method for the determination of 0.2 -1.4 mg/1 (as NH3N) of ammonia nitrogen in soil samples extractable by 2 M potassium chloride. The soil suspension in 2 M potassium chloride is centrifuged and filtered and introduced into the flow injection system for the analysis of ammonia (and nitrate) one parameter at a time. Ammonia is determined by the gas diffusion principle, in which a PTFE membrane is mounted in the gas diffusion cell. 

Tecator Ltd. (1983) Determination of Ammonia Nitrogen in Soil Samples Extractable by2M KC1 using Flow Injection Analysis, Application Note ASN 65-32/83, Tecator Ltd., Bristol, UK. 

Ammonia Content The concentration of ammonia nitrogen present in the water-extractable components of the fabric was determined colormetrically by Nessler s reaction (2,13). Nessler s Reagent reacts with ammonia released from ammonium salts by KOH producing a yellow compound under alkaline conditions by the following reaction ... 

At pH levels below 7, the above equihbrium is shifted to the right and the predominant nitrogen species is NH4, the ionized form. On the other hand, when the pH is above 7, the equilibrium is shifted to the left and the predominant nitrogen species is ammonia. The unionized form is most lethal to aquatic life. Ammonia is determined in the laboratory by boiling off with the steam after raising the pH. The steam is then condensed absorbing the ammonia liberated. The concentration is measured by colorimetric methods in the condensed steam. 

In superchlorination, breakpoint reactions like Eqs. (17.37) to (17.42) will transpire. A host of other reactions may also occur such that all these, as shown by the preceding reactions, produce acids. The number of reactions are many, therefore, it is not possible to predict the amount of acids produced by using simple stoichiometry. The only way to determine this amount is to run ajar test as is done in the determination of the optimum alum dose. Metcalf Eddy, Inc. wrote that in practice it is found that 15.0 mg/L of alkalinity is needed per mg/L of ammonia nitrogen (Metcalf Eddy, Inc., 1972). But, again, the best method would be to run the jar test. 

Ammonia. Ammonia is determined acidimetrically. A 100-mg. sample is dissolved in dilute sulfuric acid, and the mixture is heated until it is free from nitrogen(II) oxide. The solution is then transferred to a standard Kjeldahl apparatus and made alkaline with 30% sodium hydroxide, and the ammonia is distilled over into 25 ml. of 0.1 M hydrochloric acid. 

Analytical control followed the Standard Methods recommendations [ 4 ]. Metal ion concentrations were determined by a Perkin-Elmer Model 4000 Atomic Absorption Spectrophotometer with zinz lamp 303-6081, lead lamp 303-6039, and copper lamp 303-6024. Determination of dissolved sulfide was done by titrimetric iodine methods. Phenol determination was performed by distillation/ex-traction method. Total cyanide and ammonia nitrogen were detrmined by the respective distillation/titrimetric methods. 

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