Separation and recovery of copper metal from ammoniacal solutions

摘要

Copper is recovered from solutions containing cupric ammoniacal complexes by reducing copper in the complexes to the cuprous state and thereafter precipitating the copper as cuprous acetylide by passing acetylene through the solution. After the cuprous acetylide is separated from the solution and washed thoroughly, it is reacted with acetonitrile and an acid to form acetylene and a cuprous-acetonitrile complex: Cu(CH3CN)2+. The solution containing this complex is then flash distilled to remove the acetonitrile and to disproportionate unstable cuprous ions into copper metal and cupric ions. Following the disproportionation, the components are separated and copper metal is collected.