Column bioleaching of metals from electronic scrap

The present work was aimed at studying the column bioleaching feasibility of metals from electronic scrap by the selected moderately thermophilic strains of mixed adapted consortium of acidophilic chemolothotrophic and acidophilic heterotrophic bacteria. These included Sulfobacilllus thermosulfidooxidans and Thermoplasma acidophilum. The tolerance of bacterial cultures to mixed metal ions (Ag+, Al3+, Cu2+, Fe3+, Ni2+, Pb2+, Sn2+ and Zn2+) could be improved markedly after nearly two year adaptation from 12 g/L to 20 g/L. During whole leaching process included acid pre-leaching operation of 27 days and bioleaching operation of 280 days about 80% Zn, 64% Al, 86% Cu and 74% Ni was leached out. (C) 2009 Elsevier B.V. All rights reserved.