摘要 |
<p>A method for producing copper from a solution of copper nitrate comprises converting at least some of this copper nitrate to Cu (NH3)4 (NO3)2 by the addition of ammonia, treating this solution with SO2 to give a crystalline precipitate which is then treated with H2SO4 to form metallic copper. Alternatively air or oxygen may be used instead of H2SO4 to give a mixture of copper and its oxide from which the latter may be removed by treatment with H2SO4. A further alternative comprises heating the crystalline precipitate in the absence of oxygen to form a mixture of Cu and its oxide and sulphide. This mixture is then heated in a reducing atmosphere to produce copper metal.</p> |