This study level process design represents an economically viable method for extracting thorium dioxide and other rare earth elements from monazite ore. This paper incorporates results from the 2019 capstone project from the honors Design Internship in Green Engineering in Chemical and Biomolecular Engineering. In this activity, senior students in Chemical Engineering at the University of Tennessee (UT) focused on the development and study of a process for the recovery of thorium dioxide and P2O5 from monazite. While not mandated, the process offers rare earth oxides as attractive byproducts. The project focused on recovery of byproducts rather than the creation or addition to waste streams. Additionally, (1) the process economics relied heavily on recovery of rare earth byproducts, (2) thorium handling portions of the process could be effectively segregated from rare earth and phosphate handling portions of the process, and (3) thorium and uranium content of waste streams should be carefully managed and eliminated where possible.
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OLI Systems Inc. provided assistance in development of computer-aided process modeling.
This research is funded by the Electric Power Research Institute (EPRI).
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Bennett, B., Counce, R.M., Zhang, P. et al. Conceptual Process to Produce ThO2 from Monazite. Mining, Metallurgy & Exploration 37, 1317–1327 (2020). https://doi.org/10.1007/s42461-020-00203-y
- Chemical engineering
- Process design
- Rare earth elements