POTASSIUM CYANIDE

PRODUCT IDENTIFICATION
CAS NO. 151-50-8

POTASSIUM CYANIDE

EINECS NO. 205-792-3
FORMULA KCN
MOL WT.

65.12

H.S. CODE

 2837.19
TOXICITY Oral rat LD50: 5 mg/kg
SYNONYMS Hydrocyanic acid, potassium salt
Cyanide of Potassium; Potassium Salt of Hydrocyanic Acid; Kaliumcyanid (Dutch); Cianuro de potasio (Spanish); Cyanure de potassium (French); 
DERIVATION  

CLASSIFICATION
CYANIDE /

PHYSICAL AND CHEMICAL PROPERTIES
PHYSICAL STATE White deliquescent granular solid.
MELTING POINT

634 C

BOILING POINT 1625 C
SPECIFIC GRAVITY 1.52
SOLUBILITY IN WATER 71.6 g/100ml
pH 11 (0.1 N aqueous solution)
VAPOR DENSITY 2.2

AUTOIGNITION

 

NFPA RATINGS

 Health: 4; Flammability: 0; Reactivity: 0

REFRACTIVE INDEX

 

FLASH POINT Not considered to be a fire hazard
STABILITY Stable under ordinary conditions

GENERAL DESCRIPTION & APPLICATIONS
Hydrogen cyanide is a highly toxic clear to pale blue liquid or gas with the odor of bitter almonds. It melts at -14 C and boils at 25.6 C. It is miscible in water or ethanol and is slightly soluble in ether. Its water solution, called hydrocyanic acid, is a weak acid. Hydrogen cyanide is mainly obtained by the reaction of ammonia with carbon monoxide (Andrussow process) or with natural gas (methane) in the presence of rhodium/platinum catalyst at approximately 1100 C. Very short contact time (milliseconds) is required to obtain the optimum yield and consequently a high operating temperature is required to reach equilibrium. It can be prepared also by the reaction of cyanide salts, e.g., calcium cyanide, with a strong acid (sulfuric acid). Hydrogen cyanide is obtained as a by-product from acrylonitrile production. But the portion is small. It is used as a fumigant in agriculture. The principal use of hydrogen cyanide is in the manufacturing of acrylates, synthetic fibers (as a starting material for nylon 66), plastics and cyanide salts, especially sodium cyanide to extract gold from ore. It is used in the manufacturing of organic chemicals; acrylonitrile, metal polishes, dyes, rodenticides, pesticides, synthetic fibers, plastics, and electroplating solutions. Cyanide salts are utilized in metal cleaning, tempering of steel, gardening, in ore-extracting processes, dyeing, printing and photography, electroplating (gold and silver bath), various organic reactions (Organic cyanide and nitrile synthesis) manufacture of adiponitril for nylon production.  Also used for production of monomers (e.g. acrylates) as well as in fumigants and pesticides.
SALES SPECIFICATION

APPEARANCE

White Powder or Granular

POTASSIUM CYANIDE

97.0% max

POTASSIUM HYDROXIDE

0.5% max

POTASSIUM CARBONATE

0.3% max

POTASSIUM FORMATE

0.5% max

CHLORIDE

0.05% max

WATER

0.3% max

WATER INSOLUBLES

0.1% max

TRANSPORTATION
PACKING 50kgs in Bag, 13mts in Container
HAZARD CLASS 6.1
UN NO. 1680
OTHER INFORMATION
Hazard Symbols: T+, Risk Phrases: 26/27/28-32, Safety Phrases: 1/2-7-24/25-28B-29-45
GENERAL DESCRIPTION OF CYANIDE PROCESS
Cyanide process, also known as cyanidation, is the most widely used process for extracting gold and silver from ores. The ores are powdered grounds and can be concentrated by flotation. It is then mixed with dilute solutions of sodium (or potassium or calcium) cyanide while air is bubbled through it to form the soluble complex ion, Au(CN)2-1. The precious metals are precipitated from solution by zinc. The precipitates are smelted to remove the zinc and treated with nitric acid to dissolve the silver.