Hydrogen cyanide, abbreviated AC by military, is an inorganic compound that is colorless and is extremely poisonous liquid. It has a boiling point (26°C) that is slightly more than the room temperature. The molecule of hydrogen cyanide is linear and has a triple bond that joins the carbon atom and nitrogen atom together. Hydrogen cyanide has a weak acidic mature with a pKa of 9.2 and is partially ionizes in a solution of water giving cyanide anion. A hydrogen cyanide solution in water, is referred to as hydrocyanic acid while the hydrogen cyanide salts are referred to as cyanides. Hydrogen cyanide is mainly produced on a large scale and is used as a valuable precursor to various chemical compounds that range from pharmaceuticals to polymers (CDC, 2011).
The bitter, faint and almond-like odor that is possessed by hydrogen cyanide makes the substance hard to detect. The odor that hydrogen cyanide has usually does not provide adequate warning of the levels that are hazardous. Hydrogen cyanide has been used as human poison and inhalation rodentcide due to its volatile nature due to their array composition (McKusick, 2010). The volatile compound has been used as inhalation rodenticide and human poison. The poisoning of cyanide ions is based on how hydrogen cyanide is capable of interfering with the respiratory enzymes that are iron-containing.
Hydrogen cyanide may also refer to a systemic chemical asphyxiant that is known to interfere with the usual oxygen use by almost each and every organs of the body. The exposure to AC can be very fatal since it has a systemic effect and affects mainly the organs that are very sensitive to reduced levels of oxygen. These organs include the brain, vessels transporting blood, heart and the lungs. Hydrogen cyanide has also been characterized as one of the chemicals that are used as a warfare agent (CDC, 2011).
In the production of hydrogen cyanide, the most essential process is the one invented by Leonid Andrussow known as Andrussow oxidation. In this process, ammonia and methane react at a temperature of 1200OC in oxygen and is catalyzed by platinum. (Andrussow, 1935)
2 CH4 + 2NH3 + 3O2 → 2 HCN + 6H2O
Energy released in the partial methane and ammonia oxidation is the one that powers the reaction. The energy that is required for the reaction is given by the partial oxidation of molecules of methane and ammonia.
Small hydrogen cyanide amounts are produced in the laboratory through the addition of acids to the salts of cyanide made of alkali metals. This laboratory procedure is in most cases the basis of poisoning accidents since the acid changes the cyanide salt that was not volatile into a gaseous hydrogen cyanide.
Hydrogen cyanide has been used as a precursor in the production of potassium cyanide and sodium cyanide. These products are used in the mining of silver and gold to electroplate silver and gold metals. There are other useful organic compounds that are produced from hydrogen cyanide through the cyanohydrins intermediacy. Some of the organic compounds produced include methyl methacrylate, methionine, and the chelating agents such as NTA and EDTA. Hydrogen cyanide is also added to butadiene in the production of adiponitrile through the hydrocyanation process. Adiponitrile is the precursor in the production of nylon 66 (Gail, et al., 2005).
Hydrogen cyanide is very toxic and air with a concentration of 300 mg/m3 has a capability of killing human within one hour. Higher concentrations of about 3200 mg/m3 may kill someone within one minute after exposure. The high toxicity of hydrogen cyanide is contributed to the cyanide ion that stops the cellular respiration through the inhibition of the cytochrome c oxidase enzyme that is in the mitochondria. The enzyme is necessary in the body in the processes that are involved in energy production where oxygen is mainly used (Cyanide Code, 2013).
Hydrogen cyanide has also been used as an agent of chemical warfare and is usually known as blood agent (OPCW, 2012). Symptoms that are associated with cyanide poisoning usually differ and depend on the means of exposure, the amount of hydrogen cyanide as well as the exposure time. When hydrogen cyanide is inhaled, the first symptoms to appear are increased rates of respiration and restlessness. Other signs that are common after poisoning are headache, giddiness, difficulties in respiration and palpitations. These signs are later followed by unconsciousness, convulsions, and respiratory failure. In case the poisoning is occurring in a rapid way due to high concentration of hydrogen cyanide, there is usually no time for the symptoms to manifest and the victim may collapse or die suddenly (Cyanide Code, 2013).
The treatment of the poisoning is usually given to the civilians is based on providing encouragement and enhancing the ability of the body to excrete cyanide as well as binding of cyanide in the blood. Detoxification in the body can be speeded up by supplying sulfur as sodium thiosulfate. This is facilitated by the fact that cyanide ions have a strong affinity to ferric ion (Cyanide Code, 2013).
In conclusion, hydrogen cyanide is a very poisonous substance with adverse effects to the body once exposed. The colorless and the odorless nature of hydrogen cyanide make it hard to identify and the treatment of the victims depends on the level and means of exposure, as well as the time taken. Strict measures should therefore be taken when handling the substance.
Reference List
Andrussow, L. (1935). The catalytic oxydation of ammonia-methane-mixtures to hydrogen cyanide. Angewandte Chemie, 48(37), 593–595.
CDC. (2011). HYDROGEN CYANIDE (AC) : Systemic Agent. Retrieved June 2013, 2013, from http://www.cdc.gov/niosh/ershdb/EmergencyResponseCard_29750038.html
Cyanide Code. (2013). The Cyanide Code. Retrieved June 18, 2013, from http://www.cyanidecode.org/about-cyanide-code/cyanide-code
Gail, E., Gos, S., Kulzer, R., Lorösch, J., Rubo, A., & Sauer, M. (2005). Cyano Compounds, Inorganic. Weinheim: Ullmann's Encyclopedia of Industrial Chemistry.
McKusick, V. A. (2010). CYANIDE, INABILITY TO SMELL. Retrieved June 18, 2013, from http://omim.org/entry/304300
OPCW. (2012). Hydrogen Cyanide. Retrieved June 18, 2013, from Organisation for the Prohibition of Chemical Weapons: http://www.opcw.org/about-chemical-weapons/types-of-chemical-agent/blood-agents/hydrogen-cyanide/
