Javelle water

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Javelle water

Javel water

(both: zhəvĕl`), Fr. eau de Javelle, aqueous solution of sodium or potassium hypochlorite. It was originally made near the French town of Javelle (now part of Paris) and was the first chemical bleach, a use first demonstrated by C. L. Berthollet in 1785. It was produced by passing chlorine gas through a water solution of potash (potassium carbonatepotassium carbonate,
chemical compound, K₂CO₃, white, crystalline, deliquescent substance that forms a strongly alkaline water solution. It is available commercially as a white, granular powder commonly called potash, or pearl ash.
..... Click the link for more information. ). After the invention of bleaching powderbleaching powder,
white or nearly white powder that is usually a mixture of calcium chloride hypochlorite, CaCl(OCl); calcium hypochlorite, Ca(OCl)₂; and calcium chloride, CaCl₂.
..... Click the link for more information. Javelle water was sometimes produced by reacting the bleaching powder with potash or soda ash (sodium carbonatesodium carbonate,
chemical compound, Na₂CO₃, soluble in water and very slightly soluble in alcohol. Pure sodium carbonate is a white, odorless powder that absorbs moisture from the air, has an alkaline taste, and forms a strongly alkaline water solution.
..... Click the link for more information. ). Now usually sodium hypochlorite solution, it is used in bleachingbleaching,
process of whitening by chemicals or by exposure to sun and air, commonly applied to textiles, paper pulp, wheat flour, petroleum products, oils and fats, straw, hair, feathers, and wood.
..... Click the link for more information. and as a disinfectant.

Javelle Water

an aqueous solution of sodium hypochlorite, NaCIO, with an admixture of sodium chloride, NaCl. Javelle water has a bleaching effect.

The name “Javelle water” was originally applied in 1789 to the bleaching fluid made in a chemical works in the Paris suburb of Javelle; it was made by passing chlorine into a cold solution of potassium hydroxide or potassium carbonate:

2KOH + CI₂ = 2KCIO + H₂O

K₂CO₃ + CI₂ = KCIO + KCI + CO₂

In 1822 the French pharmacist A. J. Labarraque (1777–1850), by treating a sodium carbonate solution (Na₂CO₃) with chlorine, prepared a bleaching fluid (Labarraque’s solution) that completely replaced Javelle water and was less costly to prepare. In the course of time, the name “Javelle water” was transferred to Labarraque’s solution, which, along with chlorinated lime, is used extensively for bleaching in the paper and textile industries.