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Bioleaching of copper from electronic waste (e-waste) in the form of high grade waste printed circuit boards (WPCBs) collected from obsoletemobile phones is assessed using a consortium of iron (Fe²⁺) & sulfur (S°) oxidizing bacteria in a semi-pilot reactor system. Results from the study indicated that the microorganisms were able to grow in the presence of WPCB and efficiently solubilize Cu from it. At a solid/liquid ratio of 10% (w/v)with a particle size of <250 μm, maximum bioleaching efficiency of around 95% Cu was observed in 8 days of leaching under oxidation-reduction potentials (ORP) of >600 mV and pH 1.8. In order to recover the metallic values, electrowinning (EW) of copper from the bioleach solutions was investigated in detail. Direct EW of the bioleach solution yielded low current efficiencies (66.1% over 4 h.), ascribed due to the high concentrations of iron (i.e., 9.1 g/L). As a novel approach, a …