text: Hydrogen cyanide forms in at least limited amounts from many combinations of hydrogen, carbon, and ammonia. Hydrogen cyanide is produced in large quantities by several processes and is a recovered waste product from the manufacture of acrylonitrile. In 2006, between 500 million and 1 billion pounds (between 230,000 and 450,000 t) were produced in the US.
  The most important process is the Andrussow oxidation invented by Leonid Andrussow at IG Farben in which methane and ammonia react in the presence of oxygen at about  over a platinum catalyst:
  :2 CH + 2 NH + 3 O → 2 HCN + 6 HO
  The energy needed for the reaction is provided by the partial oxidation of methane and ammonia.
  Of lesser importance is the Degussa process (BMA process) in which no oxygen is added and the energy must be transferred indirectly through the reactor wall:
  :CH + NH → HCN + 3H
  This reaction is akin to steam reforming, the reaction of methane and water to give carbon monoxide and hydrogen.
  In the Shawinigan Process, hydrocarbons, e.g. propane, are reacted with ammonia.
  In the laboratory, small amounts of HCN are produced by the addition of acids to cyanide salts of alkali metals:
  :H + NaCN → HCN + Na
  This reaction is sometimes the basis of accidental poisonings because the acid converts a nonvolatile cyanide salt into the gaseous HCN.
  Hydrogen cyanide could be obtained from potassium ferricyanide and acid:
  :6 H + [Fe(CN)] → 6 HCN + Fe