Chemical Place


Potassium Permanganate

Applications


Almost all applications of potassium permanganate exploit its oxidizing properties. As a strong oxidant that does not generate toxic byproducts, KMnO4 has many niche uses.Potassium permanganate is one of the principal chemicals used in the film and television industries to "age" props and set dressings. Its oxidising effects create "hundred year old" or "ancient" looks on hessian cloth, ropes, timber and glass.

Water treatment and disinfection:
As an oxidant, potassium permanganate can act as an antiseptic. For example, dilute solutions are used to treat canker sores (ulcers), disinfectant for the hands and treatment for mild pompholyx, dermatitis, and fungal infections of the hands or feet. Potassium permanganate is used extensively in the water treatment industry. It is used as a regeneration chemical to remove iron and hydrogen sulfide (rotten egg smell) from well water via a "Manganese Greensand" Filter. "Pot-Perm" is also obtainable at pool supply stores, is used additionally to treat waste water. Historically it was used to disinfect drinking water. It currently finds application in the control of nuisance organisms such as Zebra mussels in fresh water collection and treatment systems.

Organic synthesis:
Aside from its use in water treatment, the other major application of KMnO4 is as a reagent for the synthesis of organic compounds. Significant amounts are required for the synthesis of ascorbic acid, chloramphenicol, saccharin, isonicotinic acid, and pyrazinoic acid. A solution of KMnO4 in water, in a volumetric flask

Analytical use:
Potassium permanganate can be used to quantitatively determine the total oxidisable organic material in an aqueous sample. The value determined is known as the permanganate value. In analytical chemistry, a standardized aqueous solution of KMnO4 is sometimes used as an oxidizing titrant for redox titrations (permanganometry). In a related way, it is used as a reagent to determine the Kappa number of wood pulp. For the standardization of KMnO4 solutions, reduction by oxalic acid is often used. Aqueous, acidic solutions of KMnO4 are used to collect gaseous mercury in flue gas during stationary source emissions testing. In histology, potassium permanganate is used to bleach melanin which obscures tissue detail. Pre-treated with potassium permanganate, to obliterate Congo red reactivity, was thought to be definitive for AA amyloidsis; this is now generally considered to be unrealiable.

Fruit preservation:
Ethylene absorbents extend storage time of bananas even at high temperatures. This effect can be exploited by packing bananas in polyethylene with potassium permanganate as an ethylene absorbent, that doubles a bananas lifespan up to 3–4 weeks without the need for refrigeration. Ethylene released by the bananas encourage it to ripen; by removing it via oxidation, the bananas' ripening is delayed.

Survival kits:
Potassium permanganate is typically included in survival kits: as a fire starter (mixed with antifreeze from a car radiator or glycerin), water sterilizer, and for creating distress signals on snow.

Fire Service:
Potassium permanganate is used in the "plastic sphere dispensers" used to set backfires, burnouts and prescribed fires. Polymer spheres resembling ping-pong balls containing small amounts of permanganate are injected with ethylene glycol and projected towards the area where ignition is desired, where they spontaneously ignite seconds later. Both handheld and helicopter or boat mounted plastic sphere dispensers are used.