POTASSIUM CYANIDE (KCN)

SYNONYMS
None known.
GENERAL PRECAUTIONS
Avoid skin and eye contact ­ corrosive.
Avoid inhalation of the vapour.
Avoid ingestion.
Keep away from heat.
Keep away from strong oxidants.
Keep away from acids.
Keep the lid tightly sealed.
Wash hands thoroughly after handling.
CHARACTERISTICS
White, hygroscopic crystals or crystalline powder with characteristic odour.
HEALTH HAZARD DATA
A toxic solid which inhibits cellular respiration and in serious cases can result in death. It is a corrosive substance and can be absorbed into the body by inhalation, ingestion or through the skin. When dissolved in water it is a strong base and will react violently with acids. Acute exposure to the eyes and skin causes redness and pain. The eyes also suffer from blurred vision. Inhalation causes sore throat, faintness, laboured breath and unconsciousness. Ingestion causes painful swallowing, abdominal pain and unconsciousness.
TREATMENTS
Skin ­ remove contaminated clothing, immediately wash the affected area with large amounts of water until all evidence of the chemical has been removed (approximately 15 minutes). If irritation or burning persist seek medical attention. Wash contaminated clothing before re­use.
Eyes ­ immediately wash the affected eye with large amounts of water until all evidence of the chemical has been removed (approximately 15 minutes). Seek immediate medical attention.
Inhalation ­ remove from the area of exposure to fresh air. If breathing has ceased apply artificial respiration. Give amyl nitrate to breathe. Seek immediate medical attention.
Ingestion ­ rinse the mouth with plenty of water, give two to four glasses of water to drink and induce vomiting by touching a finger to the back of the throat. Inhale amyl nitrate and seek immediate medical attention.
INCOMPATIBILITY
Potassium cyanide is incompatible with:
Acids ­ liberates toxic and flammable hydrogen cyanide gas.
Acids ­ violent reaction.
Aluminium and zinc ­ corrosive.
Strong oxidants ­ fire and explosion.
Heating produces toxic and flammable hydrogen cyanide.
STORAGE
Store in a tightly closed container in a cool, dry atmosphere away from heat and incompatible substances.
HANDLING
Use a fume hood to keep the level of exposure below the recommended threshold limit, ie. 5 mg/m³. If the level of exposure is expected to exceed the recommended threshold then a respirator or self­contained breathing apparatus is recommended. Wear protective clothing. A long sleeved laboratory coat or gown, rubber gloves, safety goggles and a face mask as a minimum standard.
DISPOSAL
WEAR:
Long rubber gloves, self contained breathing apparatus and laboratory coat.
SPILLS:
Eliminate all sources of ignition.
1 General treatment.
Absorb the liquid with vermiculite or on paper towel. If a solid sweep on to paper towel. Place on an iron or glass dish in a fume hood. Evaporate and burn the paper.
On skin: immediately wash the affected area with soap and a large amount of water.
2 Hydrocyanic acid leak.
Turn on the fume hood. allow the gas to leak into a container of sodium hydroxide solution while stopping the leak. Add excess calcium hypochlorite to the alkali cyanide. discharge to the sewer with a large excess of water.
3 Cyanides.
Scoop into a large beaker and make alkaline with sodium hydroxide solution. Add to the slurry an excess of ferrous sulphate solution. After one hour discharge to the sewer with a large excess of water.
4 Nitriles.
Add an excess of calcium hypochlorite solution to produce a cyanate. Scoop the slurry into a large beaker. After one hour discharge to the sewer with a large excess of water. Wash the spill site with a soap solution containing some hypochlorite.
PACKAGE LOTS: Either
1 Add with stirring to strong calcium hypochlorite solution. Allow to stand for 24 hours then discharge to the sewer with a large excess of water.
OR
2 Liquid nitrile can be mixed with a flammable solvent and sprayed into an incinerator equipped with an afterburner and scrubber.
ENVIRONMENT:

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