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 manufactu re of printed circuit boards is attractive for environmental reasons a nd for the value of metals notably Cu, Pb and Sn. In this study, a sim ple aqueous nitric acid stripping solution was identified as an altern ative to the present commercial stripping solutions in respect to recy cling. Two recycling processes were studied: the electrochemical recyc ling of all metals and the combination of electrochemical deposition o f copper and precipitation of tin and lead which can be followed up by furnace recycling. The influence of important parameters were investi gated in relation to metal reclamation and the reuse of stripping solu tion. The advantages and disadvantages of the two processes and the pr ospects of their industrial application are examined. (C) 1997 Elsevie r Science B.V.