Question

1.A stockpile of approximately 50 metric tons of plutonium exists in the United States as a result of disassembling warheads from the nuclear arms race. What is the likely fate of this plutonium? (Hint: Search for plutonium disposal. Try also including United States and DOE in your search string.)

a. Some propose that the plutonium be sent to local nuclear power plants to “burn” as fissionable fuel. What are the advantages and disadvantages of such a course of action?

b. Others propose that it be stored permanently in a repository. Again, list the advantages and disadvantages.

Answer 1

Plutonium is a highly radioactive material with long of toxic effect on the body and environment. It should be handled with utmost care and ways should be devised to eliminate it entirely. There is no doubt that it possess enormous danger to the human race when used in nuclear bombs. In fact 1kg of Plutonium produces as much energy as 21000kg of TNT(TriNitro Toluene).

Plutonium is found in very small amounts in the Earth's Crust. It is formed in ores of Uranium. When Uranium breaks down, it sometimes forms Plutonium but in very small quanties. There are many Isotopes of Plutonium that are found in the nature. 15 to be precise and all of these are radioactive in nature. All isotopes are not useful. Plutonium-239 is the mostly used Isotope. Plutonium is named after the planet Pluto. The market price of 1 gram of plutonium is around $4000. So, the price of 50 metric ton material will be around $200,000,000 in the market.

Now, the question is what should be done with this very radioactive and dangerous material. Should it be destroyed by converting it in some other form, should it be stored permanently in the repository or should it be used up in the reactor to convert it into energy. All above solutions may have their pros and cons. Let's try to find the most feasible solution to this problem.

Plutonium has several uses too like it can be used in the medical industry to power the pace make in patients with heart ailments. The isotope used for this purpose is Plutonium-238 because it has no health effect on the human body. Plutonium is also a good choice for certain thermoelectric generators to produce electricity for space vehicles.

A. Using Plutonium in the Reactor

​​This kind of Plutonium is a special type of Plutonium known as Reactor Grade Plutonium.

Advantages

1. To produce electricity. In a conventional nuclear reactor, 1 kg of Pu-239 can produce sufficient heat to produce 8 million KWh of Electricity.

2. Reactor Grade Plutonium is not suitable to use in military warfares.

Disadvantages

1. It is very costly to make a Special Plutonium Reactor plant due to the less quantity of Plutonium which will make it unfeasible to get out the cost of the plant by supplying the electricity produced. Plutonium is produced by the neutron capture from U-238(followed by beta Decay). Plutonium is itself a "by-product" of the U-238. So, there is no need of making a special reactor for Plutonium

B. The most important thing that has to be seen is that what method is to be used while storing the Plutonium for a longer period of time.

Advantages:

1. Can be stored for future purposes which will give time to conduct more research to device the most optimal methods of using this Plutonium.

2. Save it from theft of any kind.

Disadvantages

1. Improper storage can lead to safety concerns that will lead to polluting the environment.

2. Plutonium metal corrodes fairly rapidly in the presence of air or water vapor. It corrodes very rapidly in the presence of hydrogen to form pyrophoric plutonium hydroxide. Plutonium when comes in contact with plastics undergoes rapid hydrolysis, which generates hydrogen. This H₂ ​will react rapidly with the plutonium to form plutonium hydride. When the plastic bag breaks open, there will be an exothermic reaction due to the oxidation of hydrides, generating flames and sparks which can lead to catastrophic events if a larger fire erupts.