Laura Stoy, Scientist

MS Chemical: Recovery of Rare Earth Elements from Coal Fly Ash


My thesis research focused on recovering rare earth elements from coal

combustion residuals, specifically coal fly ash. Existing methods to extract

rare earth elements from solids are chemical- and energy-intensive, and

their separation efficiency is low, meaning that even further processes are

required to separate each of the elements from each other. During my PhD,

I designed and optimized a more efficient and environmentally sustainable

separation process.

This novel process has a few significant advantages. Most importantly, we

combined extraction of rare earths with separation from the bulk of the

coal ash. This eliminates the need for total solid digestion, and streamlines                    Coal ash under magnification

downstream processing, both of which are chemical- and energy-intensive.

Our key reagent, an ionic liquid, can be recycled and used multiple times

without loss in performance. Finally, our process involves mild operational

conditions, much lower chemical consumption, and less waste generation.

We have published this work in the journal Environmental Science and Technology here and here.

Patent Filing

My advisor, Dr. Ching-Hua Huang, and I worked with Georgia Tech to file a provisional patent in 2019, and the utility patent in 2020. It is still pending. You can check out our patent here. If you are interested in licensing this patent, you may contact me or contact Georgia Tech directly here.

Startup Formation and Customer Discovery

We completed the I-Corps South Sites program in the Fall of 2020 to investigate the commercial viability of the technology. This included economic analyses and ~50 interviews with various stakeholders, including utility company executives, chemical processing R&D firms, and local environmental officials.We are currently exploring forming a startup, MS Chemical, to bring this process to a commercial scale. We are interested in forming partnerships with members of industry. Please contact me here to learn more.


Our funding to date has been largely research-based. This project has been funded by several scholarships including the US National Science Foundation (NSF) Graduate Fellowship ($138,000), the Georgia Power Fellowship ($18,397), and the Environmental Research and Education Foundation (EREF) scholarship ($12,000), as well as funding support from a grant from EREF ($195,917).  In May 2022, my advisor, Dr. Ching-Hua Huang, at Georgia Tech was awarded a $50k Phase 1 grant of a commercialization grant program.

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