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Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
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TY - JOUR
T1 - Insights into the continuous staggered bioleaching of pure copper from waste printed circuit boards
AU - Ilkhani, Zahra
AU - Stokes, Evie
AU - Redman, joshua
AU - Parker, Ken
AU - Aiouache, Farid
PY - 2025/4/27
Y1 - 2025/4/27
N2 - Recycling precious metals from electronic waste by bioleaching stands out as a sustainable technology for metal solubilisation using microorganisms. In this study, the recovery of pure copper from waste printed circuit boards was performed through an indirect approach by sequential bioleaching and electrowinning. The bacterium Acidithiobacillus ferrooxidans was cultivated in a stirred tank reactor for the continuousproduction of ferric iron (Fe3+) as the primary leaching agent for batch leaching at pulp densities and temperature up to 8% w/v and 40 °C, respectively. A leaching rate of 50% copper was achieved at pulp density of 6% w/v, 40 °C and 96 hours spent time. The finding was used as reference for a flow leaching operations in a continuous stirred tank reactor and rates of 100% and 80% of copper were leached with and without pH control, respectively, at 40 °C and a hydraulic residence time of 96 hours. A rate of 70.85% of pure copper was then recovered from the metal rich solution by electrowinning using a current density of 0.0168 A/cm2 over 8 hours. These results provide valuable insights into the continuous recovery of copper from electronic wastes and contributes to the ongoing strategies of design and scaleup toward industrially viable operations.
AB - Recycling precious metals from electronic waste by bioleaching stands out as a sustainable technology for metal solubilisation using microorganisms. In this study, the recovery of pure copper from waste printed circuit boards was performed through an indirect approach by sequential bioleaching and electrowinning. The bacterium Acidithiobacillus ferrooxidans was cultivated in a stirred tank reactor for the continuousproduction of ferric iron (Fe3+) as the primary leaching agent for batch leaching at pulp densities and temperature up to 8% w/v and 40 °C, respectively. A leaching rate of 50% copper was achieved at pulp density of 6% w/v, 40 °C and 96 hours spent time. The finding was used as reference for a flow leaching operations in a continuous stirred tank reactor and rates of 100% and 80% of copper were leached with and without pH control, respectively, at 40 °C and a hydraulic residence time of 96 hours. A rate of 70.85% of pure copper was then recovered from the metal rich solution by electrowinning using a current density of 0.0168 A/cm2 over 8 hours. These results provide valuable insights into the continuous recovery of copper from electronic wastes and contributes to the ongoing strategies of design and scaleup toward industrially viable operations.
KW - Waste printed circuit board
KW - Bioleaching
KW - Continuous stirred tank reactor
KW - Electrowinning
KW - Electronic waste
KW - Acidophilic microorganism
U2 - 10.1016/j.jenvman.2025.125522
DO - 10.1016/j.jenvman.2025.125522
M3 - Journal article
VL - 384
JO - Journal of Environmental Management
JF - Journal of Environmental Management
SN - 0301-4797
M1 - 125522
ER -