| 摘要 |
<p>PURPOSE:To recover valuable metals from solder plated metals, by subjecting the solder plated metals to an alkaline electrolysis treatment to roughly strip the solder, then stripping the residual solder with a soln. mixture composed of ferric chloride and hydrochloric acid. CONSTITUTION:The solder and/or tin plated metals (alloys, etc., of copper, iron, etc.) are subjected to the alkaline electrolysis treatment by which the solder and/or tin is roughly stripped therefrom. The alkaline electrolysis is executed at and for about 100-300A/m<2> current density, about 65-70 deg.C electrolyte temp. and about 16-28hr electrolysis time. The concn. of caustic soda is confined to about 50-150g/l to recover the greater part of the solder and/or tin in the form of metal in the case of using the caustic soda. The metals are then immersed for about 5-10min in the soln. mixture composed of about 10-15g/l ferric chloride and about 10-70g/l hydrochloric acid at about ordinary temp. and while the metals are kept rotated, the residual solder and/or tin is stripped therefrom. The valuable metals are thereby recovered at the low cost.</p> |
