Electrochemical recycling of tin, lead and copper from stripping solution in the manufacture of circuit boards

The recycling of metals from stripping solutions used in the manufacture of printed circuit boards is attractive for environmental reasons and for the value of metals notably Cu, Pb and Sn. In this study, a simple aqueous nitric acid stripping solution was identified as an alternative to the present commercial stripping solutions in respect to recycling. Two recycling processes were studied: the electrochemical recycling of all metals and the combination of electrochemical deposition of copper and precipitation of tin and lead which can be followed up by furnace recycling. The influence of important parameters were investigated in relation to metal reclamation and the reuse of stripping solution. The advantages and disadvantages of the two processes and the prospects of their industrial application are examined. (C) 1997 Elsevier Science B.V.