Sodium Hypochlorite applications
Sodium hypochlorite is most often encountered as a pale greenish-yellow dilute solution, commonly known as liquid bleach or simply bleach, a household chemical widely used as a disinfectant or bleaching agent. The compound in solution is unstable and easily decomposes, liberating chlorine, which is the active principle of such products. Indeed, sodium hypochlorite is the oldest and most important chlorine-based bleach
Sodium Hypochlorite for Bleaching
Household bleach is, in general, a solution containing 3–8% sodium hypochlorite, by weight, and 0.01–0.05% sodium hydroxide; the sodium hydroxide is used to slow the decomposition of sodium hypochlorite into sodium chloride and sodium chlorate.
Sodium Hypochlorite for Cleaning
Sodium hypochlorite has destaining properties. Among other applications, it can be used to remove mold stains, dental stains caused by fluorosis, and stains on crockery, especially those caused by the tannins in tea. It has also been used in laundry detergents and as a surface cleaner.
Sodium Hypochlorite for Disinfection
Sodium hypochlorite in solution exhibits broad spectrum anti-microbial activity and is widely used in healthcare facilities in a variety of settings. It is usually diluted in water depending on its intended use.
“Dakin’s Solution” is a disinfectant solution containing low concentration of sodium hypochlorite and some boric acid or sodium bicarbonate to stabilize the pH. It has been found to be effective with NaOCl concentrations as low as 0.025%.The undissociated (nonionized) hypochlorous acid is believed to react with and inactivate bacterial and viral enzymes.Neutrophils of the human immune system produce small amounts of hypochlorite inside phagosomes, which digest bacteria and viruses.
Sodium Hypochlorite for Deodorizing
Sodium hypochlorite has deodorizing properties, which go hand in hand with its cleaning properties.
Sodium Hypochlorite for Waste water treatment
Sodium hypochlorite solutions have been used to treat dilute cyanide waste water, such as electroplating wastes. In batch treatment operations, sodium hypochlorite has been used to treat more concentrated cyanide wastes, such as silver cyanide plating solutions. Toxic cyanide is oxidized to cyanate (OCN−) that is not toxic, idealized as follows:
CN− + OCl− → OCN− + Cl−
Sodium hypochlorite is commonly used as a biocide in industrial applications to control slime and bacteria formation in water systems used at power plants, pulp and paper mills, etc., in solutions typically of 10–15% by weight