makes the metal recovery environmentally required and economically interesting. ... reconsidered and special treatment techniques of isolated waste streams ...
Proceedings
SWEMP 2002, R. Ciccu (Ed.), Cagliari, Italy, October 7-10,2002
COPPER ELECTROWINNING FROM THE AMMONIACAL ETCHING EFFLUENTS OF PRINTED CIRCUIT BOARDS INDUSTRY
D. Panias, I. Giannopoulou, I. Paspaliaris National Technical University of Athens (NTUA), School of Mining and Metallurgical Engineering, Section of Metallurgy and Materials Technology, Laboratory of Metallurgy, Athens, Greece.
SUMMARY: Ammoniacal cupric chloride solution is widely used at the chemical etching process in the printed circuit board (PCB) industry to remove a metallic copper portion from the copper clad laminate. Spent etchant has a typical copper concentration in the range of 140-160 g/l, which makes the metal recovery environmentally required and economically interesting. The present work aims at studying the electrolytic recovery of copper from the ammoniacal etching effluent in a simple cell, working in batch mode. The effluent is pre-treated with a strong anionic exchange resin for the reduction of the chloride concentration to low level allowing copper electrowinning without any corrosion problems created due to anodic oxidation of chloride ions, The effects of electrode arrangement, electrolyte agitation rate, current density and copper initial concentration on current efficiency and copper recovery are investigated in this study. The results are used to determine the optimum conditions for economically feasible copper electrorecovery from the ammoniacal etching effluent. 1. INTRODUCTION The demand of printed cir
