What is plutonium
Plutonium is a chemical element, with Pu symbol and atomic number 94 belonging to the actinide element series.
Plutonium has 16 isotopes, all of which are radioactive. The element is a silvery metal and has 5 different crystalline structures.
Chemically, plutonium is a very active material. It can form compounds with all non-metallic elements except noble gases. The metal dissolves in acids and reacts with water, although moderately compared to acids.
Although traces can be found in nature, all isotopes of plutonium are of artificial origin.
Origin of Plutonium Name
His name was placed by the planet Pluto and related by the Roman God of death.
He was discovered by the Nobel Prize in Physics, Enrico Fermi.
What is plutonium?
Plutonium is an element of the periodic table that belongs to the series of elements called actinides. It is a fairly active material and can form compounds with all metallic elements.
Characteristics of plutonium
The main characteristics that we can mention are the following:
- It has an atomic number of 94.
- Its valence is 3,4,5,6
- Its oxidation state: +3
- Your electronegativity: 1,2
- Electronic configuration: [Rn]5f56d17s2
- Atomic mass (g/mol): 242
- It has a boiling point (º C): 3235
- Melting point (º C): 640
Of plutonium, 15 different isotopes (atomic forms of the same element) are known, but the main one is plutonium-239, which, combined with oxygen, is normally used as combustible material in nuclear reactors.
Origin of plutonium
Spent fuel can be managed in two different ways over the long term:
Open-loop management. In the open cycle, spent fuel is considered to be a high-level radioactive waste from the moment it is discharged from the reactor and is permanently stored.
Closed-loop management. The closed cycle consists of subjecting the spent fuel to a mechanical-chemical process, known as reprocessing or reprocessing, which separates the uranium and plutonium that still contain fission and transuranium products.
Recovered uranium and plutonium are used to make new fuel and fission and transuranium products are the high-level waste.
Despite the discovery of plutonium, it was kept secret for a while. It was named after the planet Pluto was named after it was discovered directly after Neptune.
The story begins with Enrico Fermi, who was Nobel Prize winner in Physics and who at first thought he had discovered the 94th element of the table, which he called hesperio.
However, long after he realized that it was not a new element, but a combination of barium, krypton and some other elements in smaller quantities.
In 1941, the first form of plutonium was formed by a group of scientists from the University of California.
The production of plutonium in useful quantities for the first time was an important part of the Manhattan Project during World War II, which developed the first atomic bombs.
In human activities, it is well known that plutonium is used as an explosive ingredient in nuclear weapons of mass destruction since it possesses the appropriate properties for this disastrous purpose, more precisely enriched plutonium, similar to highly enriched uranium.
Who discovered Plutonium
It was discovered in 1941 by Dr. and scientist Glenn T. Seaborg and Edwin McMillan, Kennedy, and Wahl through a bombardment of uranium deuteron in the 60-inch cyclotron at the University of California, Berkeley, Berkeley Radiation Laboratory.
What plutonium is for
Plutonium-239 is mainly used in the development of nuclear reactors and nuclear fuel. It is a major player in the development of nuclear weapons.
It can be used as a thermoelectric heat generator and has also been used in the manufacture of pacemakers.
As plutonium is created inside the fuel of nuclear reactors, it splits, thus producing energy.
During the process, other isotopes of this element also originate; some may absorb neutrons and some are fissile isotopes.
Plutonium has been used in explosives for a long time. In atmospheric tests of nuclear weapons, large amounts of plutonium have been released and subsequently dropped and deposited on the ground.
After the Second World War, the development of nuclear reactors and their fuels as useful sources of electricity production began.
The Shippingport reactor in Pennsylvania, USA, was the first to start producing energy through plutonium isotopes in 1958 and from then on its use spread rapidly.
Where plutonium is found
Plutonium is naturally present in very small amounts. However, plutonium has other pathways into the environment through leaks from nuclear reactors, weapons production plants, and research facilities. Especially in nuclear weapons testing.
Plutonium can enter surface waters from accidental releases and discharges of radioactive waste.
Soil can become contaminated with plutonium through radioactive fallout during nuclear weapons tests. Plutonium moves slowly down into the soil, into the groundwater.
Plants absorb low levels of plutonium, but these levels are not high enough to cause biomagnification of plutonium in the food chain or accumulation in animal bodies.
Plutonium is produced every time nuclear fuel is produced and nuclear reactors are burned. This fuel from nuclear reactors is made up of uranium and plutonium.
Health effects of plutonium
Plutonium is one of the most toxic substances to humans and the most hazardous exposure to health occurs as a result of a radioactive release or accident.
In that case, and when inhaled or swallowed, because plutonium does not penetrate the skin, its small particles radiate through the lungs, bones, or other important organs and can eventually cause cancer.
It also affects the immune system and causes infertility, and when inhaled or ingested in considerable quantities it causes acute radiation poisoning and death.
Effects of plutonium on the environment In the environment, as a heavy metal element, plutonium contaminates the soil through radioactive fallout’ after a leak or spill.
It can also enter surface waters and its slow, downward movement can lead to groundwater. Plutonium, specifically PU-239, has a half-life of 24,100 years and”only after 20 half-lives (482,000 years) can be said to be harmless to the environment”, according to the group of scientific and technical ecologists for a non-nuclear future.
Role of plutonium in nuclear reactors
As plutonium is generated inside the fuel of nuclear reactors, this plutonium is also fissioned, collaborating with uranium in the production of energy.
During the process, other isotopes of plutonium also originate; some are neutron-absorbing and some are fissile isotopes.
Depending on the irradiation time or the degree of burning to which the proportion of these plutonium isotopes in the fuel is reached. At reduced burns, the proportion of fissile isotopes is very high, while at high burns this proportion is reduced.
In commercial reactors, fuel elements remain in the reactor for long periods of time until the accumulation of fission products and the consumption of fissile material negate their contribution to the operation of the reactor.
Management of plutonium recovered from nuclear reactors
There are between 7 and 8 kilograms of unburned plutonium in spent fuel per tonne. This plutonium, recovered in reprocessing, can be used to replace uranium-235 in nuclear fuel by making mixed uranium oxide and plutonium oxide pellets (MOX fuel).
MOX fuel can replace enriched uranium fuel in light water nuclear reactors.
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