Process Engineering Aspects in Bioleaching
of Metals from Electronic Waste
M. Minimol, Vidya Shetty K, and M. B. Saidutta
Contents
1 E-Waste Management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
2 Bioleaching of E-Waste for Metal Recovery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
3 Process Engineering Aspects in Bioleaching . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
3.1 Biotic Factors Involved in Bioleaching . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
3.2 Abiotic Factors that Influence Bioleaching of E-Waste . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
3.3 Bioreactor Design and Its Operational Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
4 Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Abstract Obsolete electronic devices and their components majorly contributed by
the computer and mobile phone printed circuit boards (PCBs) constitute the electronic waste (e-waste). The e-wastes pose an environmental threat due to their
eco-toxicological characteristics, thus making its management a mandate through
an ecologically sustainable process. Further, the high concentration of metals in the
e-waste makes it a secondary ore for metal recovery. Bioleaching is a
bio-hydrometallurgical process, which is microbe-mediated dissolution of metals.
Different nutritional classes of microorganisms like autotrophs and heterotrophs are
active bioleaching agents of e-wastes. The mode of action of microbes for
bioleaching of metals is obscure and is believed to ensue through redox reactions,
protonic attack, or chelation. The process of bioleaching is influenced by biotic
factors like the group and class of microorganism, growth rate, metabolic activity,
etc. However, there are several abiotic factors that strongly affect the bioleaching
efficiency.
Development of a bioleaching process would need the study of various biological, nutritional, and engineering factors that influence the process. This chapter
M. Minimol, V. Shetty K (*), and M. B. Saidutta
Department of Chemical Engineering, National Institute of Technology Karnataka Surathkal,
Mangalore, India
e-mail: vidyaks95@nitk.edu.in; vidyaks68@yahoo.com
Manuel Jerold, Santhiagu Arockiasamy, and Velmurugan Sivasubramanian (eds.),
Bioprocess Engineering for Bioremediation: Valorization and Management
Techniques, Hdb Env Chem (2020) 104: 27–44, DOI 10.1007/698_2020_575,
© Springer Nature Switzerland AG 2020, Published online: 14 July 2020
27
of Metals from Electronic Waste
M. Minimol, Vidya Shetty K, and M. B. Saidutta
Contents
1 E-Waste Management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
2 Bioleaching of E-Waste for Metal Recovery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
3 Process Engineering Aspects in Bioleaching . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
3.1 Biotic Factors Involved in Bioleaching . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
3.2 Abiotic Factors that Influence Bioleaching of E-Waste . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
3.3 Bioreactor Design and Its Operational Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
4 Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Abstract Obsolete electronic devices and their components majorly contributed by
the computer and mobile phone printed circuit boards (PCBs) constitute the electronic waste (e-waste). The e-wastes pose an environmental threat due to their
eco-toxicological characteristics, thus making its management a mandate through
an ecologically sustainable process. Further, the high concentration of metals in the
e-waste makes it a secondary ore for metal recovery. Bioleaching is a
bio-hydrometallurgical process, which is microbe-mediated dissolution of metals.
Different nutritional classes of microorganisms like autotrophs and heterotrophs are
active bioleaching agents of e-wastes. The mode of action of microbes for
bioleaching of metals is obscure and is believed to ensue through redox reactions,
protonic attack, or chelation. The process of bioleaching is influenced by biotic
factors like the group and class of microorganism, growth rate, metabolic activity,
etc. However, there are several abiotic factors that strongly affect the bioleaching
efficiency.
Development of a bioleaching process would need the study of various biological, nutritional, and engineering factors that influence the process. This chapter
M. Minimol, V. Shetty K (*), and M. B. Saidutta
Department of Chemical Engineering, National Institute of Technology Karnataka Surathkal,
Mangalore, India
e-mail: vidyaks95@nitk.edu.in; vidyaks68@yahoo.com
Manuel Jerold, Santhiagu Arockiasamy, and Velmurugan Sivasubramanian (eds.),
Bioprocess Engineering for Bioremediation: Valorization and Management
Techniques, Hdb Env Chem (2020) 104: 27–44, DOI 10.1007/698_2020_575,
© Springer Nature Switzerland AG 2020, Published online: 14 July 2020
27