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The Graphite Reactor: Isotopes and a new element
The Graphite Reactor: Isotopes and a new element: http://www.oakridger.com/article/20130318/NEWS/130319906/1007/OPINION?template=printart
does the lack of proper recognition sound familiar also about what
NRU/NRX enabled Canada to do??? "“If at some time a heavenly angel
should ask what the Laboratory in the hills of East Tennessee did to
enlarge man’s life and make it better, I daresay the production of
radioisotopes for scientific research and medical treatment will surely
rate as a candidate for first place.” — Alvin Weinberg, director, Oak
Ridge National Laboratory, 1955-1973.
The late Art Rupp would agree.
He was especially proud of the Lab’s isotope development program, which
he helped create and then led.
However, in an interview in 2003
with Steve Stow for the ORNL Oral History Project, he said the isotope
program started at the Lab’s Graphite Reactor, which was built in 1943,
had not received the recognition it deserves, either locally or
nationally.
In its heyday, the program separated, purified,
promoted, packaged and scheduled the delivery of radioisotopes. The
isotopes shipped from Oak Ridge to hospitals were used to diagnose and
treat cancer and other diseases, prolonging lives. Other isotopes were
useful for industry, agriculture and research.
Also, separation work
in the program provided chemical proof for the existence of Element 61
in the periodic table. Henry Moseley, the brilliant English physicist
who was killed at the age of 27 in World War I, confirmed in 1914 the
1902 prediction that an element with this atomic number exists.
Radioactive forms of various elements, called radioisotopes, were
produced in and isolated from the spent uranium fuel of the Graphite
Reactor. This Oak Ridge facility was the world’s first continuously
operated nuclear reactor. It enabled researchers to demonstrate that
gram quantities of plutonium-239 could be produced in a reactor and
separated from the spent uranium fuel.
Researchers created other
radioisotopes, such as radioactive phosphorus, by immersing a
nonradioactive target material, such as melted sulfur in aluminum cans,
in the sea of neutrons inside the reactor.
Under John Gillette’s
stewardship, the program made up to 12,000 shipments of isotopes a year —
or 104,000 shipments between 1946 and 1957.
The first radioisotope
produced and shipped from a reactor — the Graphite Reactor — was
carbon-14. It was sent in 1946 to a hospital in St. Louis for cancer
research.
Rupp, a chemical engineer trained at Purdue University
where he was once president of the poetry club, noted New York City’s
Rockefeller Center has a statue of Prometheus, but Oak Ridge does not.
Why is this important?
The element discovered in Oak Ridge was named
after Prometheus, the titan in Greek mythology who stole fire from
Mount Olympus and brought it down to mankind.
In 1945, Jacob
Marinsky, Lawrence Glendenin and Charles Coryell isolated the new
element in a hot cell after separating rare earths from radioactive
fission products. They were members of George Boyd’s group, which
pioneered the use of ion-exchange chromatography for separating
radioisotopes.
Employing a spectroscopic method, they identified
Element 61, the only radioactive rare-earth metal. Coryell’s wife, Grace
Marie, proposed the name promethium for the new element — a suggestion
accepted by the International Union of Pure and Applied Chemistry.
“Promethium is an element that does not exist naturally on Earth,” Rupp
told Stow. Like technetium, it occurs only as a byproduct of fission.
Promethium has been identified in the spectrum of a star in the
Andromeda galaxy. Promethium made on Earth is used for atomic batteries
in missiles and spacecraft.
“Its discovery in Oak Ridge is something that has just been forgotten,” Rupp said."
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