Journal
JOURNAL OF HAZARDOUS MATERIALS
Volume 378, Issue -, Pages -Publisher
ELSEVIER
DOI: 10.1016/j.jhazmat.2019.05.041
Keywords
Waste light-emitting diodes; Direct bioleaching; Step-wise indirect bioleaching; Valuable metals; Biogenic ferric
Categories
Funding
- Tarbiat Modares University [IG-39701]
- Biotechnology Development Council of the Islamic Republic of Iran
- Iran National Science Foundation (INSF) [960704, 96002489]
Ask authors/readers for more resources
Waste light-emitting diodes (WLED) are of major interest as they are a considered secondary source of valuable metals with a high potential for polluting the environment. To recover the valuable metals from WLEDs, various methods have been applied such as direct and indirect bioleaching. A novel step-wise indirect bioleaching process has been developed in this study for recycling valuable metals from WLEDs using adapted Acidithiobacillus ferrooxidans. The ferric ion concentration was controlled at 4-5 g/L with step-wise addition of biogenic ferric for faster bioleaching rate. The results indicated the negative effect of bacterial attachment in bioleaching of WLEDs. A direct bioleaching offers low copper, nickel, and gallium leach yields, while all metals recovery improved with step-wise indirect bioleaching. At a pulp density of 20 g/L, the copper, nickel, and gallium recovery efficiency was 83%, 97%, 84%, respectively. In addition, leaching time was reduced to 15 days from 30 days. From a technological perspective, the study proved that step-wise indirect bioleaching by biogenic ferric resulted in maximum valuable metal recovery from WLEDs at a low cost and via a short, simple and environmentally-friendly process.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available