Illinois Tech reactor joins elite ranks as historic nuclear site

Los Angeles CA (SPX) Apr 24, 2025
The Armour Research Foundation Reactor at Illinois Institute of Technology has been officially designated a Nuclear Historic Landmark by the American Nuclear Society (ANS), placing it among fewer than 100 such sites in the United States. Known as "the atomic furnace," this reactor was the first nuclear facility in the world to be both privately owned and operated, representing a turning point in the evolution of nuclear science from classified wartime activity to a public endeavor driven by innovation.

"The story of the Armour Research Foundation Reactor reflects both the optimism and the challenges of embracing new technologies," said Jeff Terry, vice provost for research at Illinois Tech. "As we continue to explore the possibilities of nuclear energy today, this pioneering effort at Illinois Tech serves as a reminder of the progress made and the potential that still lies ahead."

Built in 1956 with the support of 25 industrial collaborators including IBM, Inland Steel, Caterpillar, Kimberly-Clark, U.S. Steel, and Whirlpool, the reactor played a crucial role in advancing applied nuclear research. During its 11 years of operation, it supported experiments across a diverse set of disciplines, from agricultural science and chemical engineering to food safety and medicine. Applications ranged from studying fertilizer uptake and controlling pests, to exploring catalysis and diffusion, to producing isotopes for medical diagnostics.

The reactor employed an innovative approach to safety, utilizing a liquid fuel composed of Uranium-235 dissolved as uranyl sulfate in water. This design inherently limited the risk of uncontrolled reactions. "If the reaction ran away, the liquid would expand and the change in geometry would stop the criticality," Terry explained. "It was a really clever design."

Though it ceased operations in 1967 and was decommissioned in the late 1970s, the reactor's influence persists. Its legacy as a hub of collaborative, solution-oriented nuclear science was celebrated in a dedication ceremony held on Illinois Tech's Mies Campus in the Bronzeville neighborhood on Chicago's South Side.

"In places and spaces, there's meaning," said ANS President Lisa Marshall at the event. "It's very important to have these various landmarks-and even more important for us to talk about what was done there."