Authors:

Oliver Yichi Li

Date Created:

Not specified

Course Title:

Professor:

Not specified

About Paper:

The importance of rare earth metals (REMs) and other metals has increased as technology develops and trade conflicts arise. Securing a domestic supply chain of these metals will prove vital both economically and politically. One promising source is municipal solid waste (MSW) landfills; REMs, platinum group metals (PGMs), and other valuable metals have been found in noteworthy concentrations in MSW landfills. This research aims to investigate the possibility of recovering metals from leachate by characterizing the bacteria responsible for bioleaching metals into MSW leachate. A prototype batch bioreactor was constructed and filled with simulated MSW and Type 1 water. Nickel, cobalt-chrome, and aluminum coupons were submerged into waste. The bioreactor appearance, gas production, and physical changes on the coupons were observed. Along with visual and physical observations, DNA on the surface of each coupon will be extracted and analyzed to characterize the communities responsible for bioleaching metals into leachate. The bioreactor demonstrated promising visual signs of waste decomposition and biological activity. CO2 monitoring indicated anaerobic behavior in the current bioreactor environment as concentrations exceeded 10,000 ppm. Additionally, coupon colors changed during interaction with waste. Extraction of DNA from coupons is expected to allow for characterization of the community involved in bioleaching metals and is expected to vary significantly from other materials' biofilms. The success of this research can allow manipulation of communities involved in bioleaching metals into leachate. Utilizing microbial behavior to leach and therefore recover metals from MSW waste will not only enable economic benefits but will also provide a cost-effective means in a time of increasing demand. Keywords: Landfill Leachate; Metal Recovery; Municipal Solid Waste; Rare Earth Metals; Bioreactor † Presenting Undergrad Author; ‡ Contributing Undergrad Author; * Undergrad Acknowledgment

Source:

Purdue University / 2025

Topics:

No topics listed

Co-authors:

Oliver Yichi Li