Bioleaching of Copper from Electronic Waste Using Aspergillus Niger and Acidithiobacillus

The main concern of this study is to establish a feasible and an economical method of extracting copper from electronic waste using Aspergillus Niger and Acidithiobacillus Thioxidans. Both Aspergillus Niger and Acidithiobacillus Thioxidans are known to exhibit efficient generation of organic acid and sulfuric acid respectively. To establish their leaching potential, chemical leaching tests using their specific bio-acids (citric acid and sulfuric acid) were tested. In this study, concentrated copper waste was used as the test case material. Optimum conditions for leaching were found to depend on leaching pH, types of metabolic products including ferric ions and temperature of leaching. The maximum solubilisation of copper is 82% over 24 hours of leaching, which demonstrates the potential for bioleaching as a process for recovering metals from ewaste.