RECOVERY OF COPPER FROM PRINTED CIRCUIT BOARDS WASTE BY BIOLEACHING

摘要

The present work investigated the influence of Fe~(+2) initial concentrations in the bioleaching of copper from printed circuit board using Acidithiobacillus ferrooxidans-LR. Printed circuit boards were collected from obsolete computers and mechanically processed through size reduction followed by magnetic separation. The bacteria Acidithiobacillus ferrooxidans-LR were grown and adapted in presence of printed circuit boards. A shake flask study was carried out on the printed circuit boards samples (non-magnetic fraction) using a rotary shaker under the following fixed conditions (185 rpm, 30°C). The bioleaching efficiency was evaluated by comparison between the concentration in the initial sample and in the leached liquor, pH of the medium and concentration of ferrous iron produced. Inductively coupled plasma optical emission spectrometry (ICP-OES) was used to determine the metals concentration. The results showed that Acidithiobacillus ferrooxidans-LR leached 63% copper from printed circuit boards using supplemented medium with Fe~(+2).