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1. Nuclear reprocessing

2. Nuclear reprocessing is the chemical separation of fission products and actinides from spent nuclear fuel .[1] Originally , reprocessing was used solely to extract plutonium for producing nuclear weapons . With commercialization of nuclear power , the reprocessed plutonium was recycled back into MOX nuclear fuel for thermal reactors .[2] The reprocessed uranium , also known as the spent fuel material , can in principle also be re-used as fuel , but that is only economical when uranium supply is low and prices are high . Nuclear reprocessing may extend beyond fuel and include the reprocessing of other nuclear reactor material , such as Zircaloy cladding .

3. The high radioactivity of spent nuclear material means that reprocessing must be highly controlled and carefully executed in advanced facilities by specialized personnel . Numerous processes exist , with the chemical based PUREX process dominating . Alternatives include heating to drive off volatile elements , burning via oxidation , and fluoride volatility ( which uses extremely reactive Fluorine ). Each process results in some form of refined nuclear product , with radioactive waste as a byproduct . Because this could allow for weapons grade nuclear material , nuclear reprocessing is a concern for nuclear proliferation and is thus tightly regulated

4. Relatively high cost is associated with spent fuel reprocessing compared to the once-through fuel cycle , but fuel use can be increased and waste volumes decreased .[3] Nuclear fuel reprocessing is performed routinely in Europe , Russia , and Japan . In the United States , the Obama administration stepped back from President Bush’s plans for commercial-scale reprocessing and reverted to a program focused on reprocessing-related scientific research .[4] Not all nuclear fuel requires reprocessing ; a breeder reactor is not restricted to using recycled plutonium and uranium . It can employ all the actinides , closing the nuclear fuel cycle and potentially multiplying the energy extracted from natural uranium by about 60 times .

5. The first large-scale nuclear reactors were built during World War II. These reactors were designed for the production of plutonium for use in nuclear weapons . The only reprocessing required , therefore , was the extraction of the plutonium ( free of fission-product contamination ) from the spent natural uranium fuel . In 1943, several methods were proposed for separating the relatively small quantity of plutonium from the uranium and fission products . The first method selected , a precipitation process called the bismuth phosphate process , was developed and tested at the Oak Ridge National Laboratory (ORNL) between 1943 and 1945 to produce quantities of plutonium for evaluation and use in the US weapons programs . ORNL produced the first macroscopic quantities ( grams ) of separated plutonium with these processes .