Sustainable Bioleaching of Rare Earth Elements fromIndustrial Waste Materials Using Agricultural Wastes

Agricultural waste was used as substrate for fermentation by Gluconobacter oxydans to produce lixiviant for rare earth element (REE) recovery from industrial waste materials, i.e., spent fluid catalytic cracking (FCC) catalysts. Biolixiviant generated from potato wastes performed comparably to that generated from refined glucose. Corn stover yielded a slightly less effective biolixiviant but may serve as a better industrial substrate since collection systems for stover are already in development and have been implemented in several locations. Techno-economic analysis indicated that the use of agricultural waste carbon could lead to a more cost-effective bioleaching process than refined glucose. Analyses suggested that a corn stover-based bioleaching plant would have 20% lower total costs than a potato wastewater-based plant, and a potato wastewater-based plant should have 18% lower total costs compared to a glucose-based plant. An environmental life cycle analysis showed no clear winner among the three al...