Chlorine Products | CTL Scientific Supply

Quick Navigation

Our Products What is Chlorine? How to measure Chlorine Where is Chlorine monitored? Literature

Chlorine Products

Chlorine is a chemical element and halogen. It is almost exclusively manufactured using electrolysis (chloralkali process) and is used for a wide variety of applications.

Additionally, chlorine is widely used for disinfection of swimming pools, water mains, and water reservoirs. Electroplaters use chlorine for the detoxification of cyanide-containing waste. Regular monitoring of chlorine level is essential as excessive chlorine not only impairs the smell and taste of water but can also be hazardous.

Image

Product Name

Type

Gradation of scale or limit of sensitivity

Item #

Order

Chlorine Test paper

Semi-quantitative test paper

0 · 10 · 50 · 100 · 200 mg/L Cl₂

90709

	roll of 5 meter length	$8.85

Semi-quantitative test paper for the determination of chlorine. The test is particularly suitable for high range applications in disinfectant solutions which are for example used in food and beverage industry and animal farms.

Instruction Sheet (pdf)

Color reaction: white → blue-violet

Scope of delivery: 1 reel of 5 m length and 10 mm width

Chlortesmo

Qualitative test paper

1 mg/L Cl₂

90603

	box of 200 strips	$69.70

This test paper allows the quick and easy detection of free halogens (chlorine, bromine, iodine). Free nitrous acid HNO₂ (not nitrite ions) interferes, but can be destroyed by addition of amidosulphuric acid.

Instruction Sheet (pdf)

Color Reaction: pale yellow → blue

Scope of delivery: 200 test strips in a plastic box

Chlorine Test strip

Semi-quantitative test paper

0 · 2 · 10 · 50 · 100 · 200 mg/L total chlorine

90633

	tube of 200 strips	$8.10

Semi-quantitative test strips for the determination of total chlorine.

Instruction Sheet (pdf)

Scope of delivery: Tube of 200 strips

QUANTOFIX® Chlorine Sensitive

Semi-qualitative test strips

0 · 0.1 · 0.5 · 1 · 3 · 10 mg/L Cl₂

91339

	box of 100 strips	$37.00

These test strips allow the quick and easy detection of low range total Chlorine (total chloramines). The easy dip-and-read procedure provides reliable results within 20 sec. QUANTOFIX® Chlorine Sensitive test strips are the perfect choice when it is necessary to determine low range chlorine.

Instruction Sheet (pdf)

Color Reaction: yellow → violet

Scope of delivery: 100 test strips in a tube, instruction leaflet

QUANTOFIX® Chlorine Sensitive 1

Semi-quantitative test strips

0 · 0.05 · 0.1 · 0.2 · 0.4 · 0.8 · 1.2 mg/L Cl₂

91360

	box of 50 strips	$21.40

This test allows the quick and easy determination of Chlorine in solutions. It comes with all necessary reagents so that the measurement can immediately be started. Within 1 minute one gets a reliable result.

Instruction Sheet (pdf)

Color Reaction: white → blue-green

Scope of delivery: 50 test strips in a tube, instruction leaflet

QUANTOFIX® Total Chlorine Sensitive 1

Semi-qualitative test strips

0 · 0.01 · 0.05 · 0.1 · 0.2 · 0.4 · 0.8 mg/L Cl₂

91361

	box of 50 strips	$21.20

Test sticks for the semi-quantitative determination of total chlorine concentrations as low as 0.01 mg/L (ppm). A hole in the plastic carrier allows the water to migrate through the test pad, providing a high level of sensitivity.

Instruction Sheet (pdf)

Color Reaction: white → blue-green

Scope of delivery: 50 test strips in a tube, instruction leaflet

QUANTOFIX® Chlorine 500

Semi-quantitative test strips

0 · 25 · 50 · 100 · 250 · 500 mg/L Cl₂

91354

	box of 100	$26.40

Semi-quantitative test strips for the determination of chlorine. Ideal for rapid and easy analysis of chlorine directly on-site. No maintenance or calibration is required.

Instruction Sheet (pdf)

Color Reaction: white → blue-green to orange-brown

Scope of delivery: 100 test strips in a tube, instruction leaflet

Oxidizer Test Strips/Potassium Iodide Starch Paper

Semi-qualitative test strips

0 · 2 · 8 · 25 · 70 · 100 mg/L free Cl₂

90631

	tube of 100 strips	$6.90

Semi-quantitative test strips for the detection of chlorine and nitrite. Color chart with 5 steps from 2 to 100 ppm.

Scope of delivery: Tube of 100 strips

VISOCOLOR® ECO Chlorine 2, Free and Total

Colorimetric test kit

<0.1 · 0.1 · 0.2 · 0.3 · 0.4 · 0.6 · 0.9 · 1.2 · 2.0 mg/L Cl₂

931015

	1 kit (~150 tests)	$66.25

Colorimetric test kit for the determination of Chlorine in water samples. VISOCOLOR ECO Chlorine 2, free and total combines easy performance with high measurement safety, by color and turbidity compensation. For visual determination by comparison with a color chart or photometric measurement with our compact photometers.

Instruction Sheet (pdf)

Sea water analysis: No

Scope of delivery: Reagents for 150 tests, color chart and accessories in a box

VISOCOLOR® ECO Chlorine 2

Photometric test paper

<0.1 · 0.1 · 0.2 · 0.3 · 0.4 · 0.6 · 0.9 · 1.2 · 2.0 mg/L Cl₂

931016

	1 kit (~150 tests)	$71.80

Colorimetric test kit for the determination of Chlorine in water samples. VISOCOLOR ECO free Chlorine 2 combines easy performance with high measurement safety, by color and turbidity compensation. For visual determination by comparison with a color chart or photometric measurement with our compact photometers.

Instruction Sheet (pdf)

Sea water analysis: No

Scope of delivery: Reagents for 150 tests, color chart and accessories in a box

VISOCOLOR® Powder Pillows Free Chlorine For use on photometers

Photometric test paper

0.03 - 6.00 mg/L Cl₂

936220

	100 POWDER PILLOWS	$28.65

Reagent powder pillows for photometric determination of free chlorine. Powder pillows combine easy dosing with Photometric precision. Ideal for pool or drinking water analysis.

Instruction Sheet (pdf)

Sea water analysis: Yes

Scope of delivery: 100 Powder Pillows in a bag

VISOCOLOR® Powder Pillows Free Chlorine for use on photometers

Photometric test paper

0.03 - 6.00 mg/L Cl₂

936220.1

	1000 POWDER PILLOWS	$256.95

Reagent powder pillows for photometric determination of free chlorine. Powder pillows combine easy dosing with photometric precision. Ideal for pool or drinking water analysis.

Instruction Sheet (pdf)

Sea water analysis: Yes

Scope of delivery: 1000 Powder Pillows in a bag

VISOCOLOR® Powder Pillows Total Chlorine for use on photometers

Photometric test paper

0.03 - 6.00 mg/L Cl₂

936221

	100 POWDER PILLOWS	$28.70

Reagent powder pillows for photometric determination of total chlorine. Powder pillows combine easy dosing with photometric precision. Ideal for pool or drinking water analysis. Total Ozone can also be determined from 0.03 - 4.00 mg/L.

Instruction Sheet (pdf)

Sea water analysis: Yes

Scope of delivery: 100 Powder Pillows in a bag

VISOCOLOR® Powder Pillows Total Chlorine for use on photometers

Photometric test paper

0.03 - 6.00 mg/L Cl₂

936221.1

	1000 POWDER PILLOWS	$256.90

Instruction Sheet (pdf)

Sea water analysis: Yes

Scope of delivery: 1000 Powder Pillows in a bag

NANOCOLOR® Chlorine/Ozone 2

Photometric tube test

0.05 - 2.50 mg/L Cl₂

985017

	1 pack (20 test tubes)	$49.10

Tube test for the determination of Chlorine and Ozone. Precise rapid tests for all kind of water and waste water samples. Time-saving and reliable analysis together with our NANOCOLOR photometers.

Instruction Sheet (pdf)

Sea water analysis: Yes

Scope of delivery: Rugged box with 20 test tubes. Sufficient for 20 tests

What is Chlorine?

Chlorine is a chemical element in the category of halogens. It is naturally occurring as the gas Cl₂ and is one of the most reactive elements on earth. It is highly oxidative. Chlorine and its derivatives are the most important disinfectants for disinfection of swimming pools, water mains, and water reservoirs. Electroplaters use chlorine for the detoxification of cyanide-containing waste. Regular monitoring of chlorine level is essential as excessive chlorine not only impairs the smell and taste of water but also can be hazardous.

One distinguishes between free chlorine and combined chlorine (chloroamines); the sum of both is called total chlorine.

Free Chlorine

Free chlorine is the sum of two highly reactive and disinfecting substances, which form when chlorine gas dissolves in water.

The disinfection process with free chlorine in water is called chlorination. It is commonly used in water with low organic pollutants. It is applied for the prevention of algal growth, for control of taste and odor in food, removal of elements like iron and manganese, decomposition of hydrogen sulfides or cyanides and improvements of coagulation. In terms of disinfection, chlorination is used in samples with low concentrations of hard-to-treat microorganisms, e.g. giardia or cryptosporidium.

Cl₂ + H₂O → HCIO + H⁺ + Cl^-

HCIO → H⁺ + OCI^-

HOCl = Hypochlorous acid
OCl^- = Hypochlorite ion

Combined Chlorine (Chloramines)

Chloramines, commonly known as combined chlorine, form when free chlorine is added to water containing ammonia. Chloramines are still usable for disinfection purposes, therefore this reaction can be wanted in water treatment. There are three species of chloramines depending on how much chlorine is reaction with the ammonia-ion. These are monochloramine, dichloramine and nitrogen trichloride.

The use of chloramines in disinfection is called chloramination. Because chloramines have less oxidation potential and a lower reactivity than free chlorine, they also form less side products with organic matter during disinfection. This can be beneficial, as free chlorine can form disinfection by-products such trihalomethanes. Those disinfection by-products are called DBPs and can be carcinogenic. Therefore, there is a general trend to replace chlorination with free chlorine by chloramination. In addition, the demand of chlorine is less in chloramination, due to less side reactions, which saves cost.

HCIO + NH₃ → NH₂Cl + H₂O

HCIO + NH₂Cl → NHCl₂ + H₂O

HCIO + NHCl₂ → NCl₃ + H₂O

NH₂Cl = monochloramine
NHCl₂ = dichloramine
NCl₃ = trichloramine

Total Chlorine

The sum of all free and combined chlorine species is called total chlorine. It is often determined to evaluate the level of combined chlorine by subtraction, because there is not direct measurement of combined chlorine available.

Total Chlorine = free chlorine + combined chlorine

How to Measure Chlorine

Chlorine is generally monitored by colorimetric methods. By the addition of certain reagents and buffers, chlorine reacts to form a colored product. The intensity of this color is proportional to the chlorine concentration. The color intensity is then determined visually, reflectometrically or photometrically with compact or spectro photometers.

Fig. 1: Concentration series of our NANOCOLOR Chlorine/ozone 2 tube test with increasing chlorine concentration.

Test Strips - Dip & Read

The easiest and fastest way to perform chlorine measurements are Dip & Read tests. These test strips combine fast performance with accurate results. They are based on a chemical reaction between chlorine and a dye. A redox reaction takes place and the test pads develops a certain color intensity depending on the concentration of chlorine in the sample.

Different test strips are used to perform evaluation of free or total chlorine.

We offer many different test strips and test papers in the QUANTOFIX® series.

Dip & Read Tests

Check out our selection of Dip & Read products!

View All Chlorine Test Strips →

Colorimetric test kits - Easy DPD tests

DPD (N,N-Diethyl-p-phenylendiamine) is the most commonly used substance in colorimetric chlorine test kits. It reacts with free chlorine to yield an intensively pink colored dye. The intensity of the dye is proportional to the free chlorine concentration.

In visual, colorimetric tests, like our VISOCOLOR® series, this pink-colored sample is then compared to a color scale to determine the right concentration.

VISOCOLOR® Test Kits

Check out our selection of VISOCOLOR® test kits!

View All Chlorine VISOCOLOR® Test Kits →

Photometric test kits - Precision analysis

Photometric test kits use the same DPD chemistry like colorimtetric test kits. But instead of a visual determination by eye, a photometer is used. It can detect the color intensity of the solution more accurate than the user. This enhances precision and accuracy in chlorine analysis.

We offer a range of photometric chlorine test kits in the NANOCOLOR® and VISOCOLOR® product series.

NANOCOLOR® Test Tubes

Check out our selection of NANOCOLOR® test tubes!

View All Chlorine NANOCOLOR® Test Tubes →

Where is Chlorine Monitored?

Drinking water treatment plants and distribution

Chlorine is one of the most frequently used disinfectants in drinking water treatment. It also helps in precipitation of minerals and other matter by oxidation before filtration. In many countries and regions worldwide drinking water has to be disinfected before distribution. This is done after the filtration by a repeated addition of chlorine. The chlorine levels have to be monitored, together with pH-value and temperature, at many stages of the process.

Depending on microorganisms present in the water, a residual chlorine level is adjusted before distributing the drinking water to customers. International norms carefully regulate the tolerable level of chlorine in drinking water. National laws might also restrict the maximum level of chlorine present in drinking water at the tap. National drinking water acts vary greatly in maximum chlorine concentrations allowed.

Besides disinfection, chlorine also serves for the elimination of sulfides, which causes a rotten-egg smell, ammonia and nitrogen-compounds, which can cause an unpleasant smell. Chlorine also removes iron and manganese which can cause a bitter taste and coloration of the drinking water.

In contrast to the many positive effects of chlorination, chlorine can also reacts with organic substances in the water to form so-called disinfection-by-products (DBP) which can be harmful to human health. This is another reason why chlorine levels have to be monitored carefully during drinking water production.

Waster water treatment plants

In many countries, chlorination is used as the final stage in waste water treatment. In this case the treated water is disinfected with chlorine before discharge into the receiving waters. The reason for the chlorination is the prevention of waterborne diseases from pathogens and microorganisms from the previous treatment.

A thorough dechlorination process is very important to reduce harmful effects to the receiving waters by residual chlorine in the effluent.

Industrial cooling systems

Industrial cooling systems, like cooling towers, are susceptive to algae growth and the formation of bio-films within the tubing. This bio-groth can clog the water systems. Chlorine is used to effectively prevent the bio-growth. But it has to be monitored closely, as too-low concentrations do not prevent bio-growth and too-high concentrations of chlorine can cause corrosion and damage.

Literature

Disinfectants↓

Rapid Tests Full Catalogue ↓

NANOCOLOR® Tube Tests↓

Chlorine Flyer↓

View All Literature →