The Nuclear Fuel Cycle Depleted Uranium De-Conversion Process - An Economically-Viable Solution

Nuclear power is poised to experience aammonium-hydroxide, hydrogen, hydrofluoric acid
resurgence, both in terms its widespread use andand fluorine.
in positive public perception. Building concerns3. The resulting UF6 gas is then passed through
about the effects of fossil fuels on thean enrichment process at an enrichment facility. In
environment, in addition to other factors, arethe- enrichment process, the U235 atoms present
making the nuclear power option seemin the UF6 gas are enriched from their
increasingly viable.naturally-occurring level of 0.7% of the uranium
Before uranium can be used in nuclear powermass to 3-5%.
plants, it must first be enriched. During that4. The enriched UF6 is then converted into
process, however, only 10% of the naturaluranium oxide and fabricated into nuclear fuel.
uranium entering the enrichment process is5. However, during the enrichment process
useable. The remaining 90% is a by-product ofapproximately 90% of the UF6 emerges as
the enrichment process and is referred to asdepleted UF6 tails (as mentioned above), which
"depleted" uranium or "tails." These depleted tailscontain greatly-reduced levels of U235.
are in a chemically reactive form (UF6) andThe depleted UF6 tails have historically been
cannot be disposed - without chemical treatment.stored in large (typically 14-ton) steel cylinders. In
They must either be stored perpetually infact, in the United States there is already over 1.6
enormous steel drums - or it must bebillion pounds of stored UF6 tails in existence. And
de-converted into non-reactive (or less-reactive)notably, the estimated generation of depleted UF6
solids for safe disposal in landfills.outside the U.S. exceeds 250 million pounds per
Historically, there has been no economic incentiveyear.
for de-converting the depleted UF6 tails, and all ofSeveral companies have announced that they are
the depleted UF6 that has been created on U.S.evaluating, planning, or building, new uranium
soil has been simply stored on an ongoing basisenrichment facilities in the U.S. When these
since the early 1950's. However, there is currentlyfacilities are completed, at their initial stated
a shift taking place from foreign-based enrichmentcapacity, they will produce in excess of
to domestic U.S. enrichment. This shift will cause aapproximately 80 million pounds per year of
massive buildup of these depleted tails at thedepleted UF6. The proper management and
commercial enrichment sites.storage of these domestically-produced depleted
Fortunately, a new type of de-conversion processUF6 tails will become an -important issue
called the Fluorine Extraction Process (FEP)confronting the nuclear industry.
extracts high-purity fluoride compounds fromFortunately, a newly-patented de-conversion
depleted uranium during the de-conversionprocess, called the Fluorine Extraction Process
process, allowing new and useful products to be(FEP), will be able to process these uranium tails
created as a result. This new process helps tointo a form more conducive to long-term storage.
create an economic incentive for theAt the same time, the process will be able to
de-conversion of the tails.extract the fluoride in the form of important
The Fuel Cycle and Depleted Uraniumcommercial products. This will be done in such an
To understand the role of de-conversion and howefficient manner that it will save the emission of
the FEP can accomplish it more efficiently thanmillions of pounds of CO2 emissions as compared
with traditional de-conversion processes, a shortto production of those fluoride products by
overview of the nuclear fuel cycle is in order:conventional means.
1. A form of uranium, enriched in the U235FEP can be used to produce a variety of fluoride
isotope, is used as fuel in nuclear reactors. Ingases, including boron trifluoride (BF3), germanium
order to enrich this uranium for use as nucleartetrafluoride (GeF4), silicon tetrafluoride (SiF4), and
fuel, the uranium that is mined from the earthpossibly several others. These specialty gases are
must be converted into - uranium oxide or "yellowin ever-increasing demand for ion-implantation,
cake."etchants, and chemical vapor deposition processes
2. The yellow cake is then converted to UF6 gasfor microelectronics components and solar energy
through a multi-step chemical process involvingapplications and organic complexes for the
chemicals such as nitric acid,petroleum industry.