Potassium hypochlorite explained

Potassium hypochlorite is a chemical compound with the chemical formula, also written as KClO. It is the potassium salt of hypochlorous acid. It consists of potassium cations and hypochlorite anions . It is used in variable concentrations, often diluted in water solution. Its aqueous solutions are colorless liquids (light yellow when impure) that have a strong chlorine smell. It is used as a biocide and disinfectant.

Preparation

Potassium hypochlorite is produced by the disproportionation reaction of chlorine with a solution of potassium hydroxide:[1]

This is the traditional method, first used by Claude Louis Berthollet in 1789.

Another production method is electrolysis of potassium chloride solution.With both methods, the reaction mixture must be kept cold to prevent formation of potassium chlorate.

Uses

Potassium hypochlorite is used for sanitizing surfaces as well as disinfecting drinking water. Because its degradation leaves behind potassium chloride rather than sodium chloride, its use has been promoted in agriculture, where addition of potassium to soil is desired.[2]

History

Potassium hypochlorite was first produced in 1789 by Claude Louis Berthollet in his laboratory located in Javel in Paris, France, by passing chlorine gas through a solution of potash lye. The resulting liquid, known as "Eau de Javel" ("Javel water"), was a weak solution of potassium hypochlorite. Due to production difficulties, the product was then modified using sodium instead of potassium, giving rise to sodium hypochlorite, widely used today as a disinfectant.

Safety and toxicology

Like sodium hypochlorite, potassium hypochlorite is an irritant. It can cause severe damage on contact with the skin, eyes, and mucous membranes.[3] Inhalation of a mist of KOCl can cause bronchus and lung irritation, difficulty breathing, and in severe cases pulmonary edema. Ingestion of strong concentrations can be lethal.[4] Symptoms of contact or inhalation can be delayed.

Potassium hypochlorite is not considered to cause a fire or explosive hazards by itself. However, it can react explosively with numerous chemicals, including urea, ammonium salts, methanol, acetylene, and many organic compounds. Heating and acidification can produce toxic chlorine gas.[5] Containers may explode upon exposure to heat. Potassium hypochlorite forms highly explosive upon contact with urea or ammonia.

Notes and References

  1. Book: Uri Zoller, Paul Sosis. Handbook of Detergents, Part F: Production. CRC Press. 452. 4 May 2016. 9781420014655. 20 November 2008.
  2. Web site: Enviro Klor: 12.5% POTASSIUM HYPOCHLORITE BLEACH ALTERNATIVE. 14 September 2014. https://web.archive.org/web/20140915073111/http://www.envirotech.com/pdf/EnviroKlor.pdf. 15 September 2014. dead.
  3. https://federalregister.gov/a/2011-4534, Environmental Protection Agency
  4. Web site: Material Safety Data Sheet: Potassium Hypochlorite. www.kasteelchemicals.com/. 15 September 2014.
  5. Web site: Potassium Hypochlorite. Chemical Book. 15 September 2014.