Ferrate iron (Fe6+) as an alternative method for the detoxification of cyanide and cyanide species in gold cyanidation leach tails

Abstract

The super oxidative properties of ferrate (VI) iron was investigated in an attempt to determine its destruction efficiency on the cyanide ion, cyanide containing species, and the resulting derivatives of the oxidative process. The species included free cyanide and the complexes of copper, nickel, silver, and thiocyanate respectively. Additionally, in an effort to harness the ferrate breakdown product of ferric hydroxide, the removal of heavy metals was also investigated. The studies were conducted in Newmont facilities on controlled synthetic solutions as well as "real world" tailings from Newmont owned properties. It was established that, irrespective of metal specie studied, cyanide detox by ferrate was achieved.