Nitrite Test Kits
|Range||MDL||Method||Type||Kit Cat. No.||Refill|
|0.0 - 2.5 ppm as N||0.2 ppm||Azo Dye Formation||CHEMets||K-7004||R-7002|
|0 - 80 ppm as N||4 ppm||Azo Dye Formation||VACUettes||K-7004D||R-7002D|
|0 - 170 ppm as N||10 ppm||Azo Dye Formation||VACUettes||K-7004A||R-7002A|
|0 - 300 ppm as N||20 ppm||Azo Dye Formation||VACUettes||K-7004B||R-7002B|
|0 - 3,000 ppm as N||200 ppm||Azo Dye Formation||VACUettes||K-7004C||R-7002C|
|250 - 2,500 ppm as NaNO2||250 ppm||Ceric Sulphate Titrant w/Ferroin Indicator||Titrets||K-7025|
|500 - 5,000 ppm as NaNO2||500 ppm||Ceric Sulphate Titrant w/Ferroin Indicator||Titrets||K-7050|
|Range||Method||Type||Kit Cat. No.|
|0 - 1.00 ppm as N||Azo Dye Formation||Vacu-vials||K-7003|
CHEMetrics offers test kits employing the well-known Azo Dye Formation and Ceric Sulphate Titrimetric Methods to deliver sensitivity and accuracy within two minutes or less. Based on CHEMetrics patented Self-Filling Reagent Ampoule technology. Premixed. Premeasured. Precise. Each kit contains 30 tests.
The Azo Dye Formation Method
Nitrite diazotizes with a primary aromatic amine in an acidic solution to produce a highly colored azo dye. The intensity of the color is directly proportional to the concentration of nitrite in the sample. Nitrate will not interfere. Results are expressed as ppm (mg/l) NO2-N.
APHA Standard Methods, 22nd ed., Method 4500-NO2¯ B- 2000. USEPA Methods for Chemical Analysis of Water and Wastes, Method 354.1 (1983).
The Ceric Sulphate Titrimetric Method
Ceric sulphate is the titrant and ferroin is the end point indicator. The method is free from glycol interference in samples that contain up to 75 % glycol, making it particularly applicable to systems that contain nitrite corrosion inhibitors. Results are expressed as ppm (mg/l) NaNO2.
Krom, Michael D., Spectrophotometric Determination of Ammonia: A Study of a Modified Berthelot Reduction Using Salicylate and Dichloroisocyanurate, The Analyst, v.105, pp. 305-316, 1980.
Nitrite, an intermediate in the nitrogen cycle, is formed during the decomposition of organic matter but readily oxidises to form nitrate. These processes occur in wastewater treatment plants, water distribution systems, and natural waters. Nitrites are useful as corrosion inhibitors, preservatives, pigments, and in manufacturing many organic preservative chemicals. Nitrite is a possible byproduct of the use of the disinfectant chloramine. The Prescribed Concentration or Value (PCV) for nitrite in the UK is 0.5 mg/l (ppm) in drinking water supplies and 0.1 mg/l at water treatment works. The Parametric Value for Ireland in drinking water supplies is the same.