Gaseous Diffusion

DOE-HDBK-1113-98

Radiological Safety Training for Uranium Facilities

Module 102 The Nuclear Fuel Cycle

The methods used to enrich uranium include:

Gaseous Diffusion

Gaseous diffusion is based on principles of gas laws. The UF6 gas is

forced through converters by large compressors. The converters contain

many tubes made of a special barrier material that is porous. The 235UF6

molecules are lighter than the 238UF6 molecules and bounce against the

porous barrier more frequently. The 235UF6 has a greater chance of

passing through the barrier, resulting in a slightly richer 235U content. It

may take as many as a thousand passes to obtain the desired degree of

enrichment.

Laser Processes

The Atomic Vaporization Laser Isotope Separation (AVLIS) involves

vaporization, selective ionization of one isotope, and subsequent electrical

separation. Currently, no DOE production plants exist which use this

technology.

Nozzle Separation

The nozzle separation process is based on the different speeds of 235U

and 238U compounds when they are injected through a nozzle into a small

chamber.