cyanidaatio
Cyanidation, also known as the cyanide process, is a hydrometallurgical technique used primarily for extracting precious metals, gold and silver, from ore. It relies on the ability of cyanide ions to form stable, water-soluble complexes with these metals. The most common reagent used is sodium cyanide (NaCN) or potassium cyanide (KCN).
The process typically involves crushing and grinding the ore to increase the surface area. This finely ground
4 Au + 8 NaCN + O2 + 2 H2O → 4 Na[Au(CN)2] + 4 NaOH
The gold-cyanide complex (sodium aurocyanide) dissolves into the aqueous solution, separating it from the solid waste
The dissolved gold is subsequently recovered from the PLS. Two common methods are the Merrill-Crowe process,