Experimental study demonstrates high-yield metal recovery from printed circuit boards using Bacillus strains, suggesting a sustainable bioprocess for e-waste remediation.
Key Points
To evaluate the metal bioleaching capabilities of Bacillus albus and Bacillus aerius strains isolated from contaminated soil for the sustainable extraction of metals from electronic waste.
Isolated Bacillus albus (GenBank PX956283) and Bacillus aerius (GenBank PX956319) from e-waste-contaminated soil.
Conducted bioleaching assays on printed circuit boards under laboratory conditions at 37°C and 150 rpm over a 5-day incubation period.
Quantified metal recovery rates using inductively coupled plasma optical emission spectroscopy (ICP-OES) and characterized structural and functional changes via FT-IR, FE-SEM, XRD, and EDS.
Bacillus albus recovered 70.98% of barium, 94.72% of iron, 83.84% of manganese, 91.41% of nickel, 95.43% of zinc, and 96.48% of lead from printed circuit boards.
Bacillus aerius achieved extraction yields of 90.78% for barium, 87.13% for iron, 79.57% for manganese, 90.8% for nickel, 97.18% for zinc, and 71.4% for lead without requiring chemical pretreatment.