Potassium hypochlorite (chemical formula KClO) is the potassium

salt Salt is a mineral composed primarily of sodium chloride (NaCl), a chemical compound belonging to the larger class of salts; salt in the form of a natural crystalline mineral is known as rock salt or halite. Salt is present in vast quant ...

hypochlorous acid Hypochlorous acid (HClO, HOCl, or ClHO) is a weak acid that forms when chlorine dissolves in water, and itself partially dissociates, forming hypochlorite, ClO−. HClO and ClO− are oxidizers, and the primary disinfection agents of chlorine sol ...

. It is used in variable concentrations, often diluted in water solution. It has a light grey color and a strong chlorine smell. It can be used as a disinfectant.

Preparation

Potassium hypochlorite is produced by the reaction of

chlorine Chlorine is a chemical element with the symbol Cl and atomic number 17. The second-lightest of the halogens, it appears between fluorine and bromine in the periodic table and its properties are mostly intermediate between them. Chlorine i ...

with a solution of

potassium hydroxide Potassium hydroxide is an inorganic compound with the formula K OH, and is commonly called caustic potash. Along with sodium hydroxide (NaOH), KOH is a prototypical strong base. It has many industrial and niche applications, most of which exp ...

: :Cl₂ + 2 KOH → KCl + KClO + H₂O This is the traditional method, first used by

Claude Louis Berthollet Claude Louis Berthollet (, 9 December 1748 – 6 November 1822) was a Savoyard-French chemist who became vice president of the French Senate in 1804. He is known for his scientific contributions to theory of chemical equilibria via the mecha ...

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.

History

Potassium hypochlorite was first produced in 1789 by Claude Louis Berthollet in his laboratory located in Javel in

Paris Paris () is the Capital city, capital and List of communes in France with over 20,000 inhabitants, most populous city of France, with an estimated population of 2,165,423 residents in 2019 in an area of more than 105 km² (41 sq mi), ma ...

, France, by passing

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 Sodium is a chemical element with the symbol Na (from Latin ''natrium'') and atomic number 11. It is a soft, silvery-white, highly reactive metal. Sodium is an alkali metal, being in group 1 of the periodic table. Its only stable ...

instead of

potassium Potassium is the chemical element with the symbol K (from Neo-Latin ''kalium'') and atomic number19. Potassium is a silvery-white metal that is soft enough to be cut with a knife with little force. Potassium metal reacts rapidly with atmosph ...

, giving rise to

sodium hypochlorite Sodium hypochlorite (commonly known in a dilute solution as bleach) is an inorganic chemical compound with the formula NaOCl (or NaClO), comprising a sodium cation () and a hypochlorite anion (or ). It may also be viewed as the sodium s ...

, widely used today as a disinfectant.

Safety and toxicology

, potassium hypochlorite is an irritant. It can cause severe damage on contact with the skin, eyes, and mucous membranes., Environmental Protection Agency
2 March 2011. Inhalation of a mist of KClO can cause bronchial irritation, difficulty breathing, and in severe cases pulmonary edema. Ingestion of strong concentrations can be lethal. Potassium hypochlorite is not considered a fire or explosive hazard 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.

References

{{DEFAULTSORT:Potassium Hypochlorite Potassium compounds Hypochlorites Antiseptics Disinfectants Oxidizing agents