Enhancement of simultaneous gold and copper recovery from discarded mobile phone PCBs using Bacillus megaterium: RSM based optimization of effective factors and evaluation of their interactions.
Bioleaching of Au from mobile phone printed circuit boards (MPPCBs) was studied, using Bacillus megaterium which is a cyanogenic bacterium. To maximize Au extraction, initial pH, pulp density, and glycine concentration were optimized via response surface methodology (RSM). Bioleaching of Cu, an important inhibitor on Au recovery, was also examined. To maximize Au recovery, the optimal condition suggested by the models was initial pH of 10, pulp density of 8.13g/l, and glycine concentration of 10g/l. Under the optimal condition, approximately 72% of Cu and 65g Au/ton MPPCBs, which is 7 times greater than the recovery from gold mines, was extracted. Cu elimination from the MPPCBs having a rich content of Au did not cause a significant effect on Au recovery. It was found that when the ratio of Cu to Au is high, Cu elimination can considerably improve Au recovery. B. megaterium could extract the total Au from PCBs containing 130g Au/ton MPPCBs.
Biotechnology Group, Chemical Engineering Department, Tarbiat Modares University, Tehran, Iran.
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M
Arshadi
Biotechnology Group, Chemical Engineering Department, Tarbiat Modares University, Tehran, Iran. Electronic address: mousavi_m@modares.ac.ir.
S M
SM
Mousavi
Biotechnology Group, Chemical Engineering Department, Tarbiat Modares University, Tehran, Iran.
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P
Rasoulnia
D000704:Analysis of Variance; D001410:Bacillus megaterium / Q000378:metabolism*; D001709:Biotechnology / Q000379:methods*; D040421:Cell Phone; D003300:Copper / Q000302:isolation & purification*; D003486:Cyanides / Q000737:chemistry / Q000378:metabolism; D059029:Electronic Waste; D005998:Glycine / Q000378:metabolism; D006046:Gold / Q000302:isolation & purification*; D006863:Hydrogen-Ion Concentration; D010316:Particle Size; D059027:Recycling / Q000379:methods
D003486:Cyanides; D006046:Gold; D003300:Copper; D005998:Glycine
Bacillus megaterium; Bioleaching; Copper inhibitory; Gold recovery; Mobile phone PCBs; Optimization