An improved process for recovering copper and tin from tinned copper

摘要

Copper and tin are separated in a process in which tinned copper is treated with an acid solution of copper sulphate, such as spent pickling liquor, under such conditions that all or substantially all of the tin associated with the copper replaces copper in the copper sulphate solution, while the copper is precipitated as metal. The tin may be recovered from the solution as hydroxide by oxidation with atmospheric oxygen, preferably by spraying through air, and the process may be a cyclic one in which acid copper sulphate is circulated through a batch of tinned copper, a source of copper such as copper scale (to replenish the copper sulphate), atmospheric oxygen (as a spray) and a filtering arrangement for removing tin hydroxide.