Potassium hypochlorite
Potassium hypochlorite
IUPAC name
Potassium hypochlorite
Other names
  • Hypochlorous acid, potassium salt (1:1)[1]
  • Potassium chloroxide
3D model (JSmol)
ECHA InfoCard 100.029.008 Edit this at Wikidata
EC Number
  • 231-909-2
UN number 1791
  • InChI=1/ClO.K/c1-2;/q-1;+1
  • [K+].[O-]Cl
Molar mass 90.55 g·mol−1
Appearance Colorless liquid (light yellow when impure) (aqueous solution)[1]
Odor Pungent irritating chlorine-like (aqueous solution)[1]
Density 1.160 g/cm3
Melting point −2 °C (28 °F; 271 K)
Boiling point 102 °C (216 °F; 375 K) (decomposes)
25%[clarification needed]
D08 (WHO)
GHS labelling:
GHS07: Exclamation markGHS09: Environmental hazard
H336, H411
P261, P271, P273, P304+P340, P312, P391, P403+P233, P405, P501
Safety data sheet (SDS) MSDS
Related compounds
Other anions
Other cations
Related compounds
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

Potassium hypochlorite is a chemical compound with the chemical formula KOCl, also written as KClO. It is the potassium salt of hypochlorous acid. It consists of potassium cations (K+) and hypochlorite anions (OCl). 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.[1] It is used as a biocide and disinfectant.[1]


Potassium hypochlorite is produced by the disproportionation reaction of chlorine with a solution of potassium hydroxide:[2]

Cl2 + 2 KOH → KCl + KOCl + H2O

This is the traditional method, first used by Claude Louis Berthollet in 1789.[3]

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.


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.[4]


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.[5] 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.[6] Symptoms of contact or inhalation can be delayed.[1]

Potassium hypochlorite is not considered to cause a fire or explosive hazards by itself.[6] 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.[7] Containers may explode upon exposure to heat.[1] Potassium hypochlorite forms highly explosive NCl3 upon contact with urea or ammonia.[1]


  1. ^ a b c d e f g h "Potassium hypochlorite".
  2. ^ Uri Zoller, Paul Sosis (20 November 2008). Handbook of Detergents, Part F: Production. CRC Press. p. 452. ISBN 9781420014655. Retrieved 4 May 2016.
  3. ^ Helmut Vogt; Jan Balej; John E. Bennett; Peter Wintzer; Saeed Akhbar Sheikh; Patrizio Gallone (2007), "Chlorine Oxides and Chlorine Oxygen Acids", Ullmann's Encyclopedia of Industrial Chemistry (7th ed.), Wiley, p. 2
  4. ^ "Enviro Klor: 12.5% POTASSIUM HYPOCHLORITE BLEACH ALTERNATIVE" (PDF). Archived from the original (PDF) on 15 September 2014. Retrieved 14 September 2014.
  5. ^ , Environmental Protection Agency.2 March 2011.
  6. ^ a b "Material Safety Data Sheet: Potassium Hypochlorite" (PDF). www.kasteelchemicals.com/. Retrieved 15 September 2014.
  7. ^ "Potassium Hypochlorite". Chemical Book. Retrieved 15 September 2014.