Bioleaching of metallic nanoparticles from e-waste and their environmental application
Bioleaching of metallic nanoparticles from e-waste and their environmental application
Motahare Haghighatjoo1 Ali Mohammadi2
1) Master student of Microbial Biotechnology, Alzahra University , Tehran ,Iran
2) Assistant professor of Microbiology , Alzahra University , Tehran , Iran
Publication :
1st conference on engineering & innovation - University of Tabriz(ncoei.ir)
Abstract :
The e-waste disposal methods have been a great challenge. The toxic substances of
electronic devices including heavy metals and plastics put the lives of living organisms
into danger. So their removal from the natural environment seems to be necessary. There
are different disposal methods like landfilling and incineration which cause a great deal
of damage to the environment. For instance emission of hazardous gases or the leakage
of heavy metals into the soil. On the other hand, the need for precious metals recovery
like gold and silver from e-waste, the use of recycling methods seems to be necessary.
But these methods are generally expensive. So applying a new alternative method is
required.
The purpose of this article is to introduce bioleaching as an alternative to conventional
disposal and recycling methods. This method is used to remove the heavy and toxic
metals and also produce metallic nanoparticles at the same time. Then the application
of nanoparticles in wastewater treatment and microplastics degradation is mentioned.
The conversion of insoluble metals to the soluble one by chemolithoautotrophic
microorganisms is called bioleaching. The Mesophilic and thermophilic bacteria like
Chromobacterium violaceum, Pseudomonas species, Sulfobacillus
thermosulfidooxidans, and Acidiphilium acidophilum can bioleaching gold, silver,
nickel, and copper of electronic wastes. There are different fungi like Aspergillus niger,
Penicillium simplicissimum, Aspergillus fumigatus, and Aspergillus flavus generate
organic acid to leach out metals like copper, lead, nickel, and aluminum. Morganella
can produce copper nanoparticles from waste materials. Different factors like the type
of microorganisms, particle sizes, temperature, and PH affect the bioleaching process.
Bioleaching is a substitution for recycling methods of electronic wastes. Various
microorganisms are used for bioleaching according to the type of desired metallic
nanoparticles. Wastewater treatment and photocatalytic degradation of microplastics are
two important applications of produced nanoparticles.
Keywords :
Biodegradation
Bioleaching
Metallic nanoparticle
Wastewater treatment