Sodium Hypochlorite Chemical
Sodium hypochlorite is a pale greenish-yellow dilute solution referred to as liquid bleach, which is a household chemical widely used as a disinfectant or a bleaching agent. In solution, the compound is unstable and easily decomposes, liberating chlorine, which is the active principle of such products. Sodium hypochlorite is the oldest and still most important chlorine-based bleach.
Uses of sodium hypochlorite
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 has destaining properties. Among other applications, Sodium hypochlorite can be used to remove mold stains, dental stains caused by fluorosis, and stains on crockery, especially those caused by the tannins in tea. Sodium hypochlorite has also been used in laundry detergents and as a surface cleaner. Sodium hypochlorite is also used in sodium hypochlorite washes.
Organic dirt exposed to Sodium hypochlorite becomes water-soluble and non-volatile, which reduces its odor and facilitates its removal.
Sodium hypochlorite in solution exhibits broad spectrum antimicrobial activity and is widely used in healthcare facilities in a variety of settings. It is usually diluted in water depending on its intended use. Strong chlorine solution is used for disinfecting areas contaminated with body fluids, including large blood spills (the area is first cleaned with detergent before being disinfected). Weak chlorine solution is a 0.05% solution of hypochlorite used for washing hands.
Dakin's Solution is a disinfectant solution containing low concentration of sodium hypochlorite and some boric acid or sodium bicarbonate to stabilise the pH.
A similar concentration of bleach in warm water is used to sanitize surfaces prior to brewing of beer or wine. Surfaces must be rinsed with sterilized (boiled) water to avoid imparting flavors to the brew; the chlorinated byproducts of sanitizing surfaces are also harmful. The mode of disinfectant action of sodium hypochlorite is similar to that of hypochlorous acid.
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.
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.