Potassium chlorate (KClO3)


Potassium chlorate (KClO3) is a chemical substance that is commonly used in agriculture as a catalyst for production of flowers and fruits out of season. It is a white and odorless powder or grain with salty taste. It is poorly soluble in water. It is a strong oxidizing substance that many countries have laws prohibiting its possession, use and distribution without permission.

Potassium chlorate can be produced by a chemical process by passing the chlorine gas through potassium hydroxide solution at high temperature or by passing the electric current through potassium hydroxide solution at 50-60 °C in which it will be crystallized in the solution.

Chemical properties
• Clear/white crystal
• Contains potassium(K), chlorine (Cl) and oxygen (O)
• Melting point of 356 °C
• Non-hygroscopic
• Flammable and explosive when heated above 400 °C
• Solublein water at approximately 7 g/100 cc
• Strong oxidizing agent that will release oxygen rapidly in large quantities to make other substances well flammable

Potassium chlorate

picture from : www.sciencemadness.org

Possible reactions
• Since potassium chlorate is a strong oxidizing agent, it can release a lot of oxygen in a short time. In addition, it is also a non-hygroscopic substance that can explode easily when it experiences an impact or friction.
• It reacts with all kinds of ammonium salts, such as ammonium chloride (NH4Cl) and ammonium sulphate ((NH4)2 SO4), along witha violent explosion.
• When mixedor in case of friction withorganic matters or agricultural materials, such as sawdust, manures, urea fertilizers, cottons, pesticides, animal feeds, oil, grease, wax, paints, clothes, paper anddry twigs, it can cause a fire or explosion.
• It can explode suddenly when exposed to sulfuric acid (H2SO4).
• If exposed to sulfur, phosphorus or sulfides and metal salts, especially copper salts, together with an ignition, an explosion will occur.
• When mixed with non-metal objects or fuels, such as charcoal, aluminum, zincor magnesium powders, it will be easily flammable and explosive.

1. Industrial benefits
Industries that use potassium chlorate at most include the productions of matches and fireworks. In addition, it is used in the textile printing and bleaching industries as well as used as a disinfectant and a cap of ammunition.
1. Match : A match’s head contains KClO3 mixed with sulfur, crushed glass, ironoxide (Fe2O3) and tallow candle and its wood is soaked with ammoniumphosphate. The sides of a match box contain red phosphorus, gum, arabica and urea formaldehyde.
2. Firework : It contains key ingredient, i.e. KClO3, charcoal powder sand sulfur, including other substances that cause colors and sounds.

2. Agricultural benefits
Potassium chlorate is widely used in agriculture as a catalyst of flowers and fruits in the off-season. It is commonly used in many types of fruit farms that help farmers produce fruits during off-season that will have a higher price per unit.

History of using potassium chlorate to accelerate the flowering of longans in Asia
The benefits of potassium chlorate for accelerating the flowering of longans in the off-season was discovered by chance by a firework maker in China around 1982 who dropped and buried his firecrackers at the base of longan trees. He observed that the longan trees flowered and produced fruits in the off-season every year. Later, there was an experiment by pouring the washing water of flower substance containers and the solution of firework substances to the base of longan trees, which was then widely known that the substances in the fireworks could make longan trees to produce their fruits in the off-season.

Nowadays, some Asian countries, i.e. China, Thailand, Myanmar and Laos, widely use potassium chlorate to accelerate the flowering of longan trees in the off-season. This substance is mostly imported from China.


Method of use
Potassium chlorate to accelerate the fruits in the off-season is generally used before the season when these fruit trees flower every year. This is done by sowing potassium chlorate or pouring water-dissolved potassium chlorate onto the tree’s base in a rate of 8 grams/square meter. After that, about 20-30 days later the fruits will appear out of the buds. This step will be done together with trimming the branches. This method should not be used during an earlier period when there are small leaves because it will produce fewer flowers.

Mechanism of flowering stimulation
When breaking, potassium chlorate will provide chlorate radials that are negative ions of ClO3 binding to nitrate reductaze produced by plants for changing nitrate (NO3) to nitrite (NO2) and amino acids for growth from mineral extraction in the soil.

A mechanism to encourage the flowering of longan trees cannot be clearly concluded. However, there are a number of research papers and several observations as follows:
• When chlorate radicals bind to nitrate reductaze to become the negative ions of ClO2, nitrate reductaze cannot work and this thus causes a disruption of growth of leaves. As a result, longan trees stimulate their flowering instead.
• When there is a disruption of growth of leaves due to the effect of negative ions of ClO2 from adding potassium chlorate, a ratio of carbon to  nitrogen (C:N ratio) in the trunk increases and therefore the longan trees change their leaf to flower buds instead.

Use and storage
• During using, rubber gloves, chemical dust mask and boots should be worn.
• Potassium chlorate in the form of solution should be used.
• During using, coveralls that canbe easily changed in case of chemical spills should be worn and immediately washed because this substance may cause a maceration of clothes.
• If clothes catch fire during using this substance, they should be sprayed with water and should never be covered with other materials.
• Smoking is prohibited during using this substance. In addition, there should never be a bonfire neat its storage area.
• This substance should be kept in a well-ventilated building at a cold and dry area with a surrounding space.
• It should be exclusively stored in a building or storage area. It should never be kept with flammable or explosive materials as mentioned above.
• It should never be stacked onto each other no more than three meters in height. There should be some woods placed as a foundation before stacking.
• This substance should never be moved by pulling or causing an impact.

• Contact with skin bothin the forms of powder and solvent can cause irritation and burning sensation.
• Contact with eyes can cause eye irritation, burning, redness and inflammation.

Ingestion can irritate the gastrointestinal system, provide toxicity to the kidneys, and break the red bloods. Getting into the body more than 5 grams may cause death.