This work reports a kinetic study of the bioleaching process for Cu extraction from waste printed circuit boards (WPCBs), using iron as an oxidant agent. The kinetic study considered both the Fe2+ oxidation by bacteria metabolism and the chemical reaction between Fe3+ and Cu within WPCBs. The model was composed of a system of three differential equations characterized by three dependent variables and seven parameters. The first equation describes the bacteria abundance trend, the second one represents the variation of Fe2+ concentration, and the third one focuses on the Cu extraction by the biogenerated Fe3+. The developed model was consistent with experimental data with an R2 higher than 0.97. The results showed that the bacteria metabolism was 1.8-2.5 times faster than the chemical reaction. The determined mathematical model, suitable for the implementation at an industrial scale, could be an important tool to predict the bioleaching mechanism in a metal recovery process.
Bioleaching of End-of-Life Printed Circuit Boards: Mathematical Modeling and Kinetic Analysis / Becci, A.; Amato, A.; Rodriguez-Maroto, J. M.; Beolchini, F.. - In: INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH. - ISSN 0888-5885. - 60:11(2021), pp. 4261-4268. [10.1021/acs.iecr.0c05566]