Location
Grand Rapids, Michigan
Start Date
14-5-2024 3:30 PM
End Date
5-2024 5:00 PM
Description
Rare earth elements (REEs) are a set of 17 elements (lanthanides plus scandium and yttrium) that are not found concentrated in large ore deposits in nature. There has been huge growth in the amount of technology that uses REEs due to their diverse properties, but REEs are difficult to mine and expensive to separate. The global supply of REEs is largely controlled by a single country (China; >95%), and the lack of a domestic supply has been identified as a vulnerability to U.S. economic security. To alleviate this vulnerability, economical extraction methods from traditionally overlooked domestic feedstocks, such coal fly ash, are being explored. Coal fly ash is a waste product produced after coal is burned for power generation. A traditional use of fly ash is as an additive to concrete. However, it is unknown whether acidified fly ash, after the recovery of REEs, may be suitable for use in concrete. This study focuses on characterizing acidified fly ash after REE extraction, with the goal of determining how much ash may be added to mortar without eliminating the functionality of the fly ash. The testing process included: (1) waste ash from the leaching process was added to mortars cubes in various fractions, (2) 28 day-cured mortar cubes were compression strength tested, and (3) before-and-after ash and mortar samples were characterized with SEM, XRF, and with synchrotron-based tools at Argonne National Laboratory.
Document Type
Presentation
Paper_Functionality of Coal Fly Ash in Mortars After Rare Earth Element Recovery
Grand Rapids, Michigan
Rare earth elements (REEs) are a set of 17 elements (lanthanides plus scandium and yttrium) that are not found concentrated in large ore deposits in nature. There has been huge growth in the amount of technology that uses REEs due to their diverse properties, but REEs are difficult to mine and expensive to separate. The global supply of REEs is largely controlled by a single country (China; >95%), and the lack of a domestic supply has been identified as a vulnerability to U.S. economic security. To alleviate this vulnerability, economical extraction methods from traditionally overlooked domestic feedstocks, such coal fly ash, are being explored. Coal fly ash is a waste product produced after coal is burned for power generation. A traditional use of fly ash is as an additive to concrete. However, it is unknown whether acidified fly ash, after the recovery of REEs, may be suitable for use in concrete. This study focuses on characterizing acidified fly ash after REE extraction, with the goal of determining how much ash may be added to mortar without eliminating the functionality of the fly ash. The testing process included: (1) waste ash from the leaching process was added to mortars cubes in various fractions, (2) 28 day-cured mortar cubes were compression strength tested, and (3) before-and-after ash and mortar samples were characterized with SEM, XRF, and with synchrotron-based tools at Argonne National Laboratory.
