Uranium-234

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Uranium-234 Full table
General
Name, symbol	Uranium-234,²³⁴U
Neutrons	142
Protons	92
Nuclide data
Natural abundance	0.0055%
Half-life	246,000 years
Parent isotopes	²³⁸Pu (α) ²³⁴Pa (β^-) ²³⁴Np (β⁺)
Decay products	²³⁰Th
Decay mode	Decay energy
Alpha decay

Uranium-234 is an isotope of Uranium. In natural uranium, ²³⁴U occurs as the decay product of ²³⁸U, but makes up only 0.0055% of the uranium because its halflife of 246,000 years is only about 1/18,000 as long as the halflife of ²³⁸U.

Extraction of ²³⁴U from natural uranium is not feasible. Pure U-234 can be extracted (by ion exchange) from pure plutonium-238 which has been aged to allow some of it to decay to ²³⁴U.

Enriched uranium contains more U-234 than natural uranium; this is a side effect of enrichment for U-235, which concentrates even lighter isotopes even more, and does not bring any benefit. Similarly, depleted uranium contains much less U-234 (around 0.001% ^[1]) which makes its radioactivity slightly more than half that of natural uranium, since natural uranium has an equilibrium concentration of ²³⁴U and therefore an equal number of decays of ²³⁸U and ²³⁴U.

²³⁴U has neutron absorption cross sections of 100 barns thermal, 700 resonance integral; thus in a thermal reactor, it is converted to fissile ²³⁵U at a faster rate than the much larger amount of ²³⁸U, with absorption cross section of 2.68, is converted to ²³⁹Pu; thus spent nuclear fuel should have around half or less of the ²³⁴U that was in the fresh fuel.

Uranium-233	Isotopes of Uranium	Uranium-235
Produced from: Plutonium-238 (α) Protactinium-234 (β-) Neptunium-234 (β+)	Decay chain	Decays to: Thorium-230 (α)