Exceedingly small amounts of Pu, attributed to the extremely rare double-beta decay of U, have been found in natural uranium samples. Plutonium was most likely formed by neutron activation of natural U at the Oklo natural reactor but if formed it has long since decayed away. Plutonium is for the most part a by-product of nuclear reactions in reactors where some of the neutrons released by the fission process convert U nuclei into plutonium. Plutonium and are the most widely synthesized isotopes.
Plutonium is synthesized by bombarding uranium with deuterons in the following first discovery reaction:. Plutonium has assumed the position of dominant importance among the transuranium elements because of its use as an explosive ingredient in nuclear weapons and the place which it holds as a key material in the development of industrial use of nuclear power.
During fission, a fraction of the binding energy, which holds a nucleus together, is released as a large amount of electromagnetic and kinetic energy which is quickly converted to thermal energy. Fission of a kilogram of plutonium can produce an explosion equivalent to 21, tons of TNT which is equivalent to about 22 million kilowatt hours of heat energy. In it was estimated that about , kg had accumulated. MOX fuel production is also a good mechanism to reduce excessive defense plutonium stockpiles for peaceful purposes, which in effect is forging "swords into plowshares.
Plutonium isotopes undergo radioactive decay, which produces decay heat. Different isotopes produce different amounts of heat per mass. Pu with a half-life of 88 years has a relatively high heat production rate which makes it useful as a power source with a long service life. Pu is a heat source in radioisotope thermoelectric generators, which are used to power spacecraft and extra-terrestrial rovers.
As a power and heat source, Pu has also been used to power instruments left on the Moon by Apollo astronauts, weather satellites and interplanetary probes and powers the Cassini Saturn mission and the Mars rovers. Plutonium was at one time used successfully to power artificial heart pacemakers but has been replaced by lithium-based primary cells. Plutonium was studied as a way to provide supplemental heat to scuba divers. Pu mixed with beryllium is a convenient method to generate neutrons. Plutonium, along with all of the other transuranium elements, is a radiological hazard and must be handled with specialized equipment and precautions.
Animal studies have found that a few milligrams of plutonium per kilogram of tissue are lethal. Plutonium is more dangerous when inhaled than when ingested. When inhaled, plutonium can pass into the bloodstream moving throughout the body and into the bones, liver, or other body organs. Plutonium that reaches body organs generally stays in the body for decades and continues to expose the surrounding tissue to radiation and thus may cause cancer.
Precautions must also be taken to prevent the unintentional formulation of a critical mass. Pure Pu metal present in sufficient quantity with an appropriate geometry can form a critical mass and pose a serious and often lethal criticality event.
Low levels of plutonium in the environment is a result of world-wide fallout from numerous above-ground nuclear tests during the Cold War now banned pose little health hazard. Disposal of plutonium waste from nuclear power plants and dismantled nuclear weapons built during the Cold War is a nuclear-proliferation and environmental concern. Although it sounds convoluted well, I guess it is convoluted , making Pu is fairly straight-forward. The science and engineering are both well-known and well-established, and its production certainly breaks no new scientific or technical ground.
As I mentioned last week, the American Pu production line shut down over two decades ago. So this option is not going to work for much longer, regardless of the future of US-Russian international relations. But if there is a Pu stockpile at LANL it would certainly be nice to tap it for space exploration — not to mention the savings in disposal costs.
Yet another way to make Pu is in a liquid fluoride thorium reactor LFTR — a reactor that uses naturally occurring thorium Th to breed U, which fissions quite nicely.
Each year, around 20 tons of plutonium is produced, according to the Los Alamos National Laboratory. Spent nuclear fuel can also be reprocessed to separate usable plutonium from other elements in the fuel. Atmospheric weapons testing in the s and s left tons of plutonium in the Earth's atmosphere that is still there today, according to the World Nuclear Association.
For the most part, plutonium isn't used for much. In fact, of the five common isotopes, only two of plutonium's isotopes, plutonium and plutonium, are used for anything at all. Plutonium is used to make electricity for space probes using radioisotope thermoelectric generators. These generators are switched on when the probes can't get enough solar power because they have traveled too far away from the sun. Some probes that use plutonium are Cassini and Galileo. When concentrated enough, plutonium undergoes a fission chain reaction.
Because of this, it is used in nuclear weapons and some nuclear reactors. In fact, one of the biggest uses for plutonium is energy. According to the World Nuclear Association, over one-third of the energy produced in most nuclear power plants comes from plutonium.
Plutonium is the main fuel in fast neutron reactors. For decades, scientists wondered why plutonium didn't act like other metals in its group. For instance, plutonium is a poor conductor of electricity and it doesn't stick to magnets. Now researchers have figured out where its "missing magnetism" has been hiding out and it has to do with the wacky behavior of the electrons in the element's outer shell. Unlike other metals, which have a set number of electrons in their outer shells, when in a ground state, plutonium can have four, five or six electrons there.
Plutonium can be found accompanying uranium minerals but only in insignificant traces. Plutonium is obtained as an industrial product in nuclear reactors. Plutonium is in the family of actinides, period 7. After melting at ,4 0C plutonium become a liquid. Plutonium is a solid at room temperature. An insignificant amount of plutonium exists in nature. Mostly, plutonium is obtained from nuclear reactions caused by humans. Natural isotopes of plutonium exist only in traces in uranium ores.
Because plutonium is very toxic, radioactive, flammable and explosive. No, plutonium is not mined. Yes, plutonium exist in the human body fortunately in minute traces. Electrons in the plutonium atom are placed in 7 energy levels. Plutonium can be found in a variety of different locations. Trace elements can be found everywhere in nature.
They tend to be found in concentrated form near uranium ores, e. The tiniest amounts of plutonium Pu can be found in uranium that we remove from the ground.
But most plutonium today is found at nuclear weapons plants or wherever nuclear weapons are kept. There is also some in nuclear fuel facilities. Certainly it is present in spent nuclear fuel. The isotopes Pu and Pu exist in nature in extremely traces in uranium deposits, as a result of nuclear reactions.. Plutonium is an artificial element.
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