@article{73ed85018187445ca66b2fdc9df67eca,
title = "Techno-economic and Life Cycle Analysis for Bioleaching Rare-Earth Elements from Waste Materials",
abstract = "A bioleaching process to extract rare-earth elements (REE) from fluidized catalytic cracking (FCC) catalysts was optimized using a heterotrophic bacterium Gluconobacter oxydans to produce organic acids from glucose. Parameters optimized included agitation intensity, oxygen levels, glucose concentrations, and nutrient additions. Biolixiviants from the optimized batch process demonstrated REE leaching efficiencies up to 56%. A continuous bioreactor system was subsequently developed to feed a leach process and demonstrated leaching efficiencies of 51%. A techno-economic analysis showed glucose to be the single largest expense for the bioleach process, constituting 44% of the total cost. The bioleaching plant described here was found profitable, although the margin was small. Lower cost carbon and energy sources for producing the biolixiviant, sourcing FCC catalysts with higher total REE content (>1.5% by mass), and improved leaching efficiencies would significantly increase the overall profit. A life cycle analysis showed that electricity and glucose required for the bioreactor had the largest potential for environmental impacts.",
keywords = "Bioleaching, End-of-life products, Life cycle analysis, Rare-earth elements, Techno-economic assessment",
author = "Thompson, {Vicki S.} and Mayank Gupta and Hongyue Jin and Ehsan Vahidi and Matthew Yim and Jindra, {Michael A.} and Van Nguyen and Yoshiko Fujita and Sutherland, {John W.} and Yongqin Jiao and Reed, {David W.}",
note = "Funding Information: We thank J. Hude (Valero) for the FCC wastes and Masaaki Tazoe and Tatsuo Hoshino (NRL Pharma, Inc., Kawasaki, Japan) for their generous donation of 2,5-diketogluconic acid. We thank D. Daubaras (INL) and D. Lacroix (University of Idaho Center for Advanced Energy Studies) for assistance with HPLC and ICP analysis. We also thank Devin Imholte (INL) for helpful discussions and information provided for the TEA and David Combs (INL) for graphic. Hongyue Jin gratefully acknowledges support from the Environmental Research & Education Foundation Scholarship. We also acknowledge the DOE Science Undergraduate Laboratory Internship program for providing Van Nguyen{\textquoteright}s, Michael Jindra{\textquoteright}s, and Matthew Yim{\textquoteright}s funding. This research was supported by the Critical Materials Institute, an Energy Innovation Hub funded by the U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy, Advanced Manufacturing Office, and conducted under DOE Idaho Operations Office Contract DE-AC07-05ID14517 and Lawrence Livermore National Laboratory Contract DE-AC52-07NA27344. Accordingly, the U.S. Government retains a nonexclusive, royalty-free license to publish or reproduce the published form of this contribution, and allow others to do so, for U.S. Government purposes. Publisher Copyright: {\textcopyright} 2017 American Chemical Society.",
year = "2018",
month = feb,
day = "5",
doi = "10.1021/acssuschemeng.7b02771",
language = "English (US)",
volume = "6",
pages = "1602--1609",
journal = "ACS Sustainable Chemistry and Engineering",
issn = "2168-0485",
publisher = "American Chemical Society",
number = "2",
}