Explore Honeywell’s Metropolis Works

Step into the heart of our operations at Honeywell’s Metropolis Works, where technological innovation meets operational excellence in the production of high-performance materials.

Metropolis, Illinois uranium hexafluoride processing facility

The Honeywell Uranium Hexafluoride Processing Facility, a uranium conversion facility, is located 1.9 miles (3 km) northwest of Metropolis, Illinois, United States.

Operational Excellence

Honeywell introduced Six Sigma as a powerful strategy to accelerate improvements in processes, products, and services, and to radically reduce manufacturing and/or administrative costs and improve quality. Honeywell has recently developed a new generation of Six Sigma, called Six Sigma Plus, that empowers its employees with the skills and tools necessary to create more value for its customers, and improve its processes, products, and services.

Health, Safety & Security Excellence

At any industrial facility, occupational health and safety is a significant concern. Honeywell-MTW works diligently to create a “zero-loss” safety culture by conducting preventive safety, loss prevention and occupational health programs, and requiring that equipment and operating practices meet all applicable regulatory requirements. Working with the U.S. Nuclear Regulatory Commission, Honeywell-MTW strives to establish systems that ensure the integrity of its facility and the safety of the surrounding community.


Built in 1958, the Honeywell Metropolis Works Facility is the only uranium hexafluoride conversion facility in the United States.

The plant feeds U3O8 yellowcake received from uranium mines and produces uranium hexafluoride gas for enrichment at one of the primary enrichment sites around the world. After being enriched, the product is fabricated into nuclear fuel that ends up generating electricity at a nuclear power plant.

Mid 1950s

U.S. Atomic Energy Commission (AEC) projects conversion needs to meet uranium requirements for nuclear power reactors


AEC invites industry bids


Allied awarded five-year contract (1959-1964)


Ground broken for plant construction


Plant completed


First UF6 deliveries to AEC


AEC contract completed; plant mothballed


Studies support operating MTW as a private conversion facility


Rehabilitation of UF6 plant completed


First deliveries to customers under toll conversion contracts
Plant capacity expanded to 9,000 mtU as UF6


Plant capacity expanded to 11,500 mtU as UF6


Calcium fluoride recovery process completed


Formation of ConverDyn


Uranium auger sampling system completed


Plant capacity expanded to 12,700 mtU as UF6


Re-engineering raises plant capacity to over 14,000 mtU as UF6


10 year license renewal granted by the U.S. NRC
Expansion completed to raise nameplate capacity to 17,600 mtU as UF6

2012 – 2013

Post-Fukushima seismic upgrades


license extension to 2060

2017 – 2023

Temporary shutdown from 2017 to 2023 due to poor market conditions


Successful restart of MTW in July 2023