TEST METHOD FOR NITRITE IN INDUSTRIAL WATER (Range: 0-2500 or above mg/L Nitrite as NO2 or NaNO2)
BACKGROUND OF THE TEST:
In closed loop cooling towers, Nitrites and Nitrite-based formulations are widely used for corrosion control.
Nuclotrasis offers user friendly test method with ease of handling the relevant reagents and other equipment in
which the sample is first acidified and hence titrated under acidic conditions by strong oxidizing agent until the color
changes from colorless to pink while the pink color should persist for one (1) minute. The test ideally covers the range
0 - 2500 mg/l Nitrite as NO2 or NaNO2.
REAGENTS/EQUIPMENTS/APPARATUS:
• Provided 5 mL & 10 mL marked glass vial (Item Code: 02-01)
• NUCLOTRASIS NITRITE-I TEST SOLUTION (Item Code: 01-10-1)
• NUCLOTRASIS NITRITE-II TITRANT SOLUTION (Item Code: 01-10-2)
SAMPLE COLLECTION & PREPARATION
• Make sure to immediately analyze the sample after collection of sample.
• Ensure to collect sample in a suitable and designated bottle for a specific sample.
• Ensure to conduct this test at room temperatures.
TEST PROCEDURE:
1. We recommend selecting the sample volume in the provided glass vial (Item Code: 02-01) based on
your expected/desired nitrites residual range from the chart below.
Sample volume
(mL)
Range
(mg/L Nitrite as NO2 or
NaNO2)
Multiplication Factor
For Result as NaNO2
Multiplication Factor
For Result as NO2
10 0-500 100 66.68
20 0-250 50 33.34
5 100-1000 200 133.36
1 500-2500 and above 1000 666.8
2. Add the selected sample volume into a conical flask and dilute to approximately 50 mL by deionized
water.
3. Then add 10 drops of NUCLOTRASIS NITRITE-I TEST SOLUTION (Item Code: 01-10-1) and swirl to mix.
4. Now start adding NUCLOTRASIS NITRITE-II TITRANT SOLUTION (Item Code: 01-10-2) drop wise with
gentle mixing and while counting the number of drops added until the pink color appears. Note here that
appeared pink color may get vanish after few seconds. So ensure that the color must persist for one (1)
minute.
5. Note the number of drops added and multiply with multiplication factor mentioned in above chart
against selected sample volume.
6. Report the final reading as required by the system.
REFERENCES:
1. Standard Methods for the Examination of Water and Wastewater