How long does it take plutonium to decompose?

Answer 1

depends on the type of waste, that determines its halflife. some waste will be safe in just a few decades, other types will take millions of years.

if they would reprocess reactor nuclear waste so that uranium, plutonium, and other transuranics were recycled as fuel instead of staying in the waste; the remaining waste could be stored in a repository for 100 to 200 years and be safe after that.

Answer 2

It would take hundreds of thousands of years for the most common isotope being synthesized, which is plutonium-239. Hundreds of tons have been produced for nuclear weapons.

The half-life of plutonium-239 is 24110 years, and it is only "lost" if it fissions in large nuclear reactors, where currently more is being produced than is used up. Decay is not a practical consideration because of the long time frame that this entails.

*Smaller power generators utilize plutonium-238 for the thermal energy released from its decay (half-life of 87.7 years).

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However much there is, it will be "gone" for practical purposes in the same number of half lives (about 5 to 10, or 120550 to 241100 years), but It will take much longer than hundreds of half-lives for it ALL to be gone, because as the number of atoms is reduced, it takes much longer for a given volume to decay.

Answer 3

There are different types (isotopes) of plutonium, and they react differently. In other words, the details of the radioactive decay depend on the specific isotope.
As an example, plutonium-239 decays into uranium-235, with a half-life of about 24,000 years. After that time, ONE-HALF of any given sample will have decayed. For individual atoms, the atom has a probability of 1/2 of decaying within one half-life.

Answer 4

Milliards of years by natural radioactive decay.

Answer 5

The half life of the most important isotope (239Pu) is 24 200 years.

For the half lives of the other isotopes see the link below.

Answer 6

The half life of the most important isotope (239Pu) is 2,41.104 years.

Answer 7

A very long time; some isotopes of plutonium have half lives of many ten thousand years.