Potassium hypochlorite, chlorination

Chlor-jod, n. iodine chloride, specif, iodine monochloride, -kali, n. chloride of potash (potassium hypochlorite) potassium chloride. -kalilOsung, /. Pharm.) solution of chlorinated potassa, Javelle water, -kalium, n. potassium chloride. 

In 1834, A. J. Balard prepd solutions of various hypochlorites by mixing aq hypochlorous acid with alkalies, magnesium, copper oxide, zinc oxide etc, avoiding an excess of acid J. L. Gay-Lussac dissolved two mols of chlorine monoxide, C120, in a solution containing 1 mol of K20 and then evaporated the resulting solution in vacuo. This gave solid potassium hypochlorite... 

Cone. soln. of sodium hypochlorite with up to 42 per cent, of available chlorine have been made under the trade name chloros, by passing chlorine into a soln. of caustic soda of such a strength that the sodium chloride which is formed separates out. The temp, is kept below 27°. The crystals of sodium chloride are removed, and more chlorine is introduced, but the sodium hydroxide is always kept in excess or the soln. will be unstable. A. J. Balard prepared potassium, sodium, and lithium hypochlorites by neutralizing a well-cooled soln. of the base with the acid. E. Soubeiian evaporated in vacuo the liquid obtained by treating a soln. of calcium hypochlorite with sodium carbonate, and obtained, before the liquid had all evaporated, crystals of sodium chloride and of sodium hypochlorite. P. Mayer and R. Schindler obtained solid potassium hypochlorite mixed with potassium hydrocarbonate by the action of chlorine—developed from 10 parts of sodium chloride—on a soln. of 24 parts of potassium hydrocarbonate and one of water. 

It will be observed that potassium hypochlorite is the first product of the action of chlorine upon potassium hydroxide, and the hypochlorite is successively converted into the chlorate or perchlorate, before it is finally all transformed into the chloride. The hypochlorite, chlorate, and perchlorate thus represent intermediate stages in the reaction 4K0H+2C12... 

In the hydrated form, Ni02.aH20, nickel dioxide is obtained by decomposing an aqueous solution of a nickel salt by warming with sodium or potassium hypochlorite, and by passing chlorine through a suspension of nickelous hydroxide in water.1 It also results when a neutral solution of nickel sulphate is electrolysed. In the literature it is frequently referred to and described as the hydrated sesqui-oxide. 

A series of monoalkylpyrazines has been chlorinated specifically at the 3-position with sulfuryl chloride in the presence of iV,V-dimethylformamide the nucleus of 2,6-dialkylpyrazines is also readily chlorinated (687,693). The reaction of isobutyl-pyrazine with phosphoryl chloride and phosphorus pentachloride gave 2-chloro-5-isobutylpyrazine in 25% yield (693). 2-Acetonylpyrazine and 2-phenacylpyrazine with aqueous potassium hypochlorite gave 2-dichloromethylpyrazine (694). 

Potassium hypochlorite, KOCI, acts like sodium hypochlorite. This reagent is prepared in situ from potassium hydroxide and chlorine and oxidizes primary alcohols to aldehydes [702] and methyl ketones to carboxylic acids [703]. 

Benzylic alcohols are successfully transformed into aldehydes by potassium hypochlorite containing 24 or 35% of available chlorine. In aqueous methanolic solution, a spontaneous exothermic reaction takes place and is finished at 36-40 °C overnight to yield 77% of benzaldehyde from benzyl alcohol [702]. 

As soon as in 1785, a solution of chlorine gas in water was used to bleach textiles. Potassium hypochlorite (Eau de Javel) was prepared by Berthollet in 1789. In 1820, Antoine G. Labarraque replaced potash liquor by the cheaper caustic soda liquor and thus was bom sodium hypochlorite. At the end of the 1820s, Robert Collins, then Oliver Wendell Holmes showed that puerperal (childbed) fever frequency decreased when midwives wash their hands... 

Hydrogen peroxide Potassium permanganate Chlorine and hypochlorite Chlorine dioxide References... 

Chemical bleaching of textiles (as opposed to bleaching by sunlight, a process known as crofting) had its advent soon after the discovery of the element chlorine by Scheele in 1774. Finding that aqueous solutions of chlorine gas weakened the fiber of textiles, Bertholet experimented with solutions of potassium hypochlorite (KOCl), made by dissolving chlorine gas in a solution of caustic potash (KOH). Labarraque made hypochlorite solutions industrially economic by replacing the more expensive caustic potash with caustic soda (NaOH). The liquid household bleach normally available today is a 5% solution of sodium hypochlorite (NaOCl). 

Hypochlorites are usually made by the same reaction that was used in 1785 to make the first hypochlorite compound. Chlorine gas was bubbled into an aqueous solution of caustic potash (potassium hydroxide) to make potassium hypochlorite, KOCl. Sodium hypochlorite, NaOCl, was not made until 1820 when caustic soda (sodium hydroxide) was used instead of caustic potash. Today, sodium hypochlorite is the major hypochlorite compound produced, and it is the hypochlorite compound that is most often used for cleaning. Potassium hypochlorite is only a minor product that is used in a limited number of cleaning products to avoid the precipitation of certain components. These compounds are almost always made and used as aqueous solutions that are called bleach. Usually the solution contains 5-6% or 12-15% sodium hypochlorite, an equal molar amount of sodium chloride, and 0.01-1% sodium hydroxide. 

Chloracne was first reported by Von Bettman in 1897. In 1899, Herxheimer used the term chloracne to describe four cases of severe acne resulting from environmental contact with electrolytically produced potassium hypochlorite. Since that time, various chloracnegenic chemicals have been identified. Chlo-ronapthalenes and polychlorinated biphenyls (PCBs) were the causative agents in the pre-World-War-II era. Since then, trace contaminants formed during the manufacture of PCBs and other polyhalogenated compounds, especially herbicides, have been the major causes of chloracne. These include polyhalogenated dibenzofurans, polychlorinated dibenzo-p-dioxins and chlorinated azo- and azoxy benzenes. 

Gaseous chlorine, chlorine dioxide (CIO2) and sodium and potassium hypochlorites (OCP) are used as bleaching agents and improvers of flour baking properties and also for chemical disinfection of water. The most frequently used agent is chlorine dioxide, in amounts of up to about 30 mg/kg flour in some countries. 

Potassium hypochlorite Content of active chlorine <150 g/l Sodium sulfide [Pg.1007]

For polyethylene, a specific verification of chemical resistance has to be provided in case of exposure to critical exposure media, such as chlorine water, potassium hypochlorite, sodium hypochlorite, nitric acid, and sulfuric acid. For polypropylene, this additional verification has to be provided for exposure to chlorine water [7],... 

Calcium Hypochlorite Calcium Oxychloride Lime Chloride Potassium Hypochlorite Potassium Perchlorate Potassium Sulfate Zinc Hydrosulfite Zinc Nitrate Fluorine Oxygen Chlorine Nitrous Acid Sulfurous Acid Hydrogen Sulfide Selenic Acid Ammonium Sulfate... 

The reagents that are used for the haloform reaction are chlorine in sodium hydroxide at 55°-80°C, aqueous sodium or potassium hypochlorite, commercial bleaching agents, iodine in sodium hydroxide, or bromine in sodium hydroxide at 0°C. 

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