Date of Award
2026
Document Type
Thesis
Degree Name
Master of Science (MS)
Department
Mechanical and Aerospace Engineering
Committee Chair
Natalie Click
Committee Member
Judith Schneider
Committee Member
Yu Lei
Research Advisor
Natalie Click
Subject(s)
Rare earth materials, Coal ash, Leaching
Abstract
Resourcing rare earth elements (REEs) from coal ash offers the opportunity to recycle industrial waste and reduce national dependence on foreign suppliers. In this research, the leaching behaviors of pond and fresh ash were studied to evaluate their suitability for REE recovery. Concentrations of REEs in leachates were measured and compared to kinetic models from literature, and the ash was analyzed using Scanning Electron Microscopy (SEM) and X-ray Diffraction (XRD) to characterize the observed behaviors. The pond ash leachate exhibited lower REE concentrations with steady release patterns, likely due to the acid resistant, REE-bearing aluminosilicate glass phases. In contrast, the fresh ash leachate displayed larger concentrations of REEs, with a distinct pattern of an initial increase and subsequent decrease, suggesting possible REE readsorption to clay minerals that formed during leaching. These insights advance the understanding of REE availability in coal ash, supporting strategies for national resource security and economic circularization.
Recommended Citation
Fleming, Christina, "Modeling and characterization of pond and fresh ash leaching in citric acid" (2026). Theses. 821.
https://louis.uah.edu/uah-theses/821