EM Quant® Chlorine Test, Catalog No. 10043
Test strips and reagent for the detection
and semi-quantitative determination of chlorine
The Chlorine Test is a rapid, semi-quantitative
exploratory test for chlorine in effluent, e.g. from electroplating
works. It can be used to control and optimize the use of chlorine in
the processes listed below (see also under Cyanide Test) as well as
for checking the use of chlorinated disinfectants.
The use of hypochlorite as a means of
detoxifying cyanide-bearing effluent is a well proven economical
procedure that is employed on a large scale. 12% sodium hypochlorite
bleaching solution or chlorine and sodium hydroxide solution are used
to convert cyanide to cyanate, which is slowly hydrolyzed to ammonium
Principle of the Method
Chlorine reacts with cyanide ions to form
cyanogen chloride, which breaks open the ring of pyridine to give
glutacondialdehyde. The barbituric acid derivative in the reaction
zone of the test strip reacts with the dialdehyde to produce a red
polymethine dye. The pH is optimized through addition of a buffer
0 -4 -12 - 40 - 120mg/l (ppm) Cl2
- Rinse the measuring vessel with some of the sample and fill to the 5ml mark.
- Determine the pH (e.g. with pH indicator strips).
- If the pH is greater than 9, add 25% sulfuric acid dropwise to adjust to pH 6-7.
- Add one level measuring spoon of reagent 1 (buffer mixture) and dissolve.
- Add 5 drops of chlorine reagent 2 and shake.
- Immediately immerse the reaction zone in the solution for 30 seconds.
- Remove the test strip, wipe off excess
liquid by stroking the edge of the strip against the rim of the
vessel and compare the reaction zone with the color scale within
Keep Reagent 2 (contains potassium cyanide and
pyridine) away from the skin. In the event of contact, rinse well
immediately with plenty of water. Seek immediate medical attention of
substance enters the eye.
If 5-10mg/l (ppm) of bromide or iodide are
present, the coloration is weaker or absent altogether.
At concentrations of 50mg/l (ppm), nitrite slightly intensifies the color,
while permanganate and chromate reduce its intensity.
In strongly acidic or alkaline solutions, interference may occur if the
buffer added does not have sufficient buffering capacity. This is why
it is important to adjust to pH 6-7 if the water is too acidic or alkaline.
Examples: to a test solution equivalent to 4% sodium hydroxide solution,
add approximately 0.8ml of 25% sulfuric acid to optimize the pH. For a
test solution equivalent to 10% sodium hydroxide solution, approximately
2ml of 25% sulfuric acid is required. The increase in volume results in
a slightly lower value than the color scale would normally show.
Add approximately 1ml of sodium hypochlorite
solution (approximately 13%) to approximately 100ml of distilled
water and accurately determine the concentration by titrimetry.
Dilute as appropriate to give the required
10043 EM Quant® Chlorine Test
Chlorine Test for 100 determinations; reagents
and accessories included.